Article

# Blocking of Pavlovian Conditioning in Humans

Authors:
To read the full-text of this research, you can request a copy directly from the authors.

## Abstract

Despite the many demonstrations of blocking in animals, there is still little evidence of blocking with human subjects, which is problematic for general learning and behavior theory. The purpose of this research was to examine blocking with human subjects using a design and behavioral procedure (conditioned suppression) similar to those commonly used in animal research. First, subjects learned an operant task. Later, they were instructed to suppress responding when a visual US was presented. Two Pavlovian acquisition phases and a test phase occurred while the subjects were performing the operant task. In the first Pavlovian phase, CS A predicted the US for the experimental group, but was uncorrelated with the US for the control group. In the second Pavlovian phase, a compound CS AX predicted the US for both groups. At test, CS X was presented to all subjects and suppression ratios were assessed. Experimental subjects suppressed responding in the presence of CS X less than did control subjects, thereby demonstrating a blocking effect. This research, in demonstrating blocking in humans, adds to the known similarities in animal and human behavior.

## No full-text available

... These difficulties have supported the contention that fundamental differences exist between human and non-human animal learning in general, and between verbal and nonverbal learning in particular (Arcediano, Matute, & Miller, 1997). While the continuity of biological principles across species is accepted, some researchers have argued that behavioural principles discovered in animals do not necessarily apply to humans (e.g., Brewer, 1974). ...
... The blocking effect was reported in human participants more recently by Arcediano, Matute, et al. (1997) and Arcediano, Escobar, and Matute (2001). They selected a "nonverbal behavioural response" (Arcediano, Escobar, et al., 2001;p. ...
... Similarly to Kamin's (1968) procedure, these researchers superimposed an aversive Pavlovian conditioning procedure on a baseline of operant responding, and measured their results in terms of suppression of the underlying operant responding. In their first study (Arcediano, Matute, et al., 1997), the control group experienced an "explicitly unpaired" procedure (p. 192), which potentially resulted in super-conditioning of the target stimulus (Droungas & LoLordo, 1995; see Appendix A) and an "apparent blocking effect" (Arcediano, Escobar, et al., 2001;p. ...
... The primary purpose of the present paper was to assess the generality of this effect and, specifically, to determine whether it could be obtained with human participants. The main difficulty in investigating reversal from blocking with human participants is that the blocking effect itself has proven to be quite elusive with humans (e.g., Davey & Singh, 1988; Lovibond, Siddle, & Bond, 1988; Pellón, García, & Sánchez, 1995), and the seemingly successful blocking studies have generally lacked adequate control groups, thereby being open to alternative interpretations (see Arcediano, Matute, & Miller, 1997, for a review). For example, we previously developed a behavioral preparation that proved effective in obtaining simple Pavlovian conditioning in humans (Arcediano, Ortega, & Matute, 1996), which seemingly yielded blocking (Arcediano et al., 1997), but in subsequent unpublished research with that preparation we had problems in obtaining blocking relative to a control condition in which participants were trained with a stimulus different from the blocking stimulus during the first phase of the blocking treatment (i.e., C–US trials followed by AX–US trials, with X being the target CS). ...
... The main difficulty in investigating reversal from blocking with human participants is that the blocking effect itself has proven to be quite elusive with humans (e.g., Davey & Singh, 1988; Lovibond, Siddle, & Bond, 1988; Pellón, García, & Sánchez, 1995), and the seemingly successful blocking studies have generally lacked adequate control groups, thereby being open to alternative interpretations (see Arcediano, Matute, & Miller, 1997, for a review). For example, we previously developed a behavioral preparation that proved effective in obtaining simple Pavlovian conditioning in humans (Arcediano, Ortega, & Matute, 1996), which seemingly yielded blocking (Arcediano et al., 1997), but in subsequent unpublished research with that preparation we had problems in obtaining blocking relative to a control condition in which participants were trained with a stimulus different from the blocking stimulus during the first phase of the blocking treatment (i.e., C–US trials followed by AX–US trials, with X being the target CS). Arcediano et al. (1997) used a control condition in which the blocking CS was uncorrelated with the US during the first phase of the blocking procedure. ...
... , 1997), but in subsequent unpublished research with that preparation we had problems in obtaining blocking relative to a control condition in which participants were trained with a stimulus different from the blocking stimulus during the first phase of the blocking treatment (i.e., C–US trials followed by AX–US trials, with X being the target CS). Arcediano et al. (1997) used a control condition in which the blocking CS was uncorrelated with the US during the first phase of the blocking procedure. The uncorrelated control condition has the advantage that subjects in both the control and the experimental conditions are exposed to the same number of presentations of the blocking CS, the blocked CS, and th ...
Article
Full-text available
In a blocking procedure, conditioned stimulus (CS) A is paired with the unconditioned stimulus (US) in Phase 1, and a compound of CSs A and X is then paired with the US in Phase 2. The usual result of such a treatment is that X elicits less conditioned responding than if the A-US pairings of Phase 1 had not occurred. Obtaining blocking with human participants has proven difficult, especially if a behavioral task is used or if the control group experiences reinforcement of a CS different from the blocking CS in Phase 1. In the present series, in which human participants and a behavioral measure of learning were used, we provide evidence of blocking, using the above described control condition. Most important, we demonstrate that extinction of the blocking CS (A) following blocking treatment reverses the blocking deficit (i.e., increases responding to X). These results are at odds with traditional associative theories of learning, but they support current associative theories that predict that posttraining manipulations of the competing stimulus can result in a reversal of stimulus competition phenomena.
... Assuming our rats entered Experiment 1 with a sweet taste→calorie association already established, consuming saccharin may have weakened this association thereby reducing the extent to which sweet taste could block (e.g., Arcediano, Matute, & Miller, 1997;Kamin, 1969;Rescorla & Holland, 1982) the formation of an association between a novel flavor cue and the caloric US (e.g., Dwyer et al. in press: Balleine, Espinet, & Gonzalez, 2005; but also see Capaldi & Hunter, 2004). One way to reduce blocking by a previously trained CS is to present that CS without its US (Bills, Dopheide, Pineno, & Schachtman, 2006). ...
... However, there is little reason to assume that the learning mechanism we propose to underlie those effects is confined to rats in the laboratory. Similar mechanisms have been shown to operate across the phylogenetic continuum, from the simple sea slug (e.g., Aplysia Californicus) to humans (e.g., Arcediano et al., 1997;Baxter & Byrne, 2006), with a diverse array of stimuli and within a wide variety of response systems (see Domjan, 2005). ...
Article
Full-text available
Recent results from both human epidemiological and experimental studies with animals suggest that intake of noncaloric sweeteners may promote, rather than protect against, weight gain and other disturbances of energy regulation. However, without a viable mechanism to explain how consumption of noncaloric sweeteners can increase energy intake and body weight, the persuasiveness of such results has been limited. Using a rat model, the present research showed that intake of noncaloric sweeteners reduces the effectiveness of learned associations between sweet tastes and postingestive caloric outcomes (Experiment 1) and that interfering with this association may impair the ability of rats to regulate their intake of sweet, but not nonsweet, high-fat and high-calorie food (Experiment 2). The results support the hypothesis that consuming noncaloric sweeteners may promote excessive intake and body weight gain by weakening a predictive relationship between sweet taste and the caloric consequences of eating.
... Although evidence for cue competition effects has been found using contingency judgement tasks or an operant suppression paradigm (Arcediano et al., 1997;Chapman, 1991;Chapman & Robbins, 1990;Dickinson, et al., 1984;Shanks, 1985;Waldmann & Holyoak, 1992), none of these studies has yielded complete blocking in human subjects.That is, in all these experiments the blocked stimulus still acquired some predictive value.These results are not in line with the Rescorla-Wagner model that predicts complete blocking since the to-be blocked stimulus was compounded with an already established predictor (see for an alternative explanation Chapter 7). ...
... The same line of reasoning can be used to explain the partial rather than complete blocking obtained in our, as well as in other human cue-interaction experiments (Arcediano et al., 1997;Chapman, 1991;Chapman & Robbins, 1990;Dickinson, Shanks, & Evenden, 1984, Shanks, 1985Waldmann & Holyoak, 1992). In all these experiments, participants received a fixed number of trials.Although we only used participants that solved the first phase of the blocking problem, this does not necessary imply that they were trained to asymptote.This leaves the possibility for the to-be blocked stimulus to acquire some predictive value during compound training (Experiment 2). ...
... This key aspect of learning is also present in human experiments. In a study, using a conditioned suppression learning paradigm, blocking was achieved in human subjects trained on an operant discrimination task based on a video game (Arcediano et al., 1997). Thought clear evidence of blocking in human experiments, these types of results are not free of controversy as several others, have failed to induce this phenomenon (Davey, 1988;Shanks and Lopez, 1996). ...
... This failed has been mainly attributed to the fact that we integrate differently the stages of training, perceiving every phase as an independent experiment (Tonneau and González, 2004). However these limitations, blocking experiments that have succeeded have used modified experimental conditions, where single-phase designed protocols appears to be a valid approach (Hinchy et al., 1995;Arcediano et al., 1997). In general, these kinds of experiments have proven that for successful associative learning to occur, the close pairing of the stimulus and thereward is of course necessary, but the predictive power of the cue at the moment of the pairing also plays an integral role. ...
Thesis
Through our senses, the brain receives an enormous amount of information. This information needs to be filtered in order to extract the most salient features to guide our behavior. How the brain actually generates different percepts and drives behavior, remain the two major questions in modern neuroscience. To answer these questions, novel neural engineering approaches are now employed to map, model and finally generate, artificial sensory perception with its learned or innate associated behavioral outcome. In this work, using a Go/noGo discrimination task combined with optogenetics to silence auditory cortex during ongoing behavior in mice, we have established the dispensable role of auditory cortex for simple frequency discriminations, but also its necessary role to solve a more challenging task. By the combination of different mapping techniques and light-sculpted optogenetics to activate precisely defined tonotopic fields in auditory cortex, we could elucidate the strategy that mice use to solve this hard task, revealing a delayed frequency discrimination mechanism. In parallel, observations about learning speed and sound-triggered activity in auditory cortex, led us to study their interactions and causally test the role of cortical recruitment in associative learning, revealing it as a possible neurophysiological correlate of saliency.
... Complete or full blocking has been demonstrated (Kamin, 1968(Kamin, , 1969, whereas others have produced more moderate (e.g., Bergen, 2002;Chase, 1966;Lyczak & Tighe, 1975;Mackintosh, 1975a) or no effects (e.g., LoLordo, Jacobs, & Foree, 1982;Maes et al., 2016). Blocking in classical conditioning has been widely demonstrated in both nonhumans (Kamin, 1969;Kim, Krupa, & Thompson, 1998;Palmer, 1988;Rescorla & Wagner, 1972) and humans (Arcediano, Matute, & Miller, 1997;Delgado, 2016). ...
... Although many experiments on blocking of both the eliciting and discriminative functions of stimuli in many different species have been published (e.g., Arcediano et al., 1997;Bergen, 2002;Blaisdell, Gunther, & Miller, 1999;Fowler, Goodman, & DeVito, 1977;Mackintosh, 1975b;Seraganian & vom Saal, 1969;Taylor, Joseph, Balsam, & Bitterman, 2008;vom Saal & Jenkins, 1970;Williams, 1975), demonstrations of blocking of conditioned reinforcing effects of stimuli are rare. Williams (1975) conducted two experiments to examine the blocking of reinforcement in a delayed reinforcement contingency in pigeons. ...
Article
Full-text available
Stimuli with no specific biological relevance for the organism can acquire multiple functions through conditioning procedures. Conditioning procedures involving compound stimuli sometimes result in blocking, related to the phenomenon of overshadowing. This can affect the establishment of conditioned stimuli in classical conditioning and discriminative stimuli in operant conditioning. The aim of the current experiment was to investigate whether a standard blocking procedure might block the establishment of a conditioned reinforcer-in addition to blocking discriminative control by that stimulus in rats. We used successive discrimination training to establish a tone or a light as a discriminative stimulus for chain pulling, upon which an unconditioned reinforcer (water) was contingent. Next, we trained a tone-light compound stimulus the same way. Finally, we conducted two tests, one for stimulus control and one for a conditioned reinforcing effect on a new response. Little or no discriminative control was evident by the second stimulus, which was added to the previously established discriminative stimulus later during training. The subsequent test showed blocking of conditioned reinforcement in five of the seven rats. Procedures that generate blocking can have a practical impact on attempts to establish discriminative stimuli and/or conditioned reinforcers in applied settings and needs careful attention.
... The experimental task is a JavaScript version of a standard behavioral preparation for the study of human predictive learning that has already been used in several studies (Arcediano, Matute, & Miller, 1997; Arcediano, Ortega, & Matute, 1996; Havermans, Keuker, Lataster, & Jansen, 2005; Lipp & Dal Santo, 2002; Matute & Pineño, 1998 ). In this task, participants are told that their objective is to prevent the landing of a group of Martians that are trying to invade the earth. ...
Article
Some published reports have emphasized the similarities between Internet and laboratory research on associative learning processes. However, few of them, if any, studied systematic divergences between both types of research methodologies. In the present experiment, we investigated these divergences using an experimental preparation for the study of associative learning. The results show that discrimination and discrimination-reversal can be obtained both in laboratory and Internet experiments. However, the learning rate was clearly better in the laboratory than in the Internet condition. This result suggests that associative learning experiments performed over the Internet should provide participants with extensive training to assure that asymptotic performance is achieved.
... The usual finding is that the exposure to reinforced A+ trials during Phase 1 suffices to prevent the new stimulus X from being conditioned (i.e., the prior knowledge about A acquired in Phase 1 " blocks " learning about X in Phase 2), or at least to impair the expression of conditioning to X. The blocking effect has been reported both in nonhumans (e.g., Kamin, 1968) and humans (e.g., Arcediano, Matute, & Miller, 1997; Shanks, 1985), in a wide variety of experimental preparations. ...
Article
Additivity-related assumptions have been proven to modulate blocking in human causal learning. Typically, these assumptions are manipulated by means of pretraining phases (including exposure to different outcome magnitudes), or through explicit instructions. In two experiments, we used a different approach that involved neither pretraining nor instructional manipulations. Instead, we manipulated the causal structure in which the cues were embedded, thereby appealing directly to the participants' prior knowledge about causal relations and how causes would add up to yield stronger outcomes. Specifically, in our "different-system" condition, the participants should assume that the outcomes would add up, whereas in our "same-system" condition, a ceiling effect would prevent such an assumption. Consistent with our predictions, Experiment 1 showed that, when two cues from separate causal systems were combined, the participants did expect a stronger outcome on compound trials, and blocking was found, whereas when the cues belonged to the same causal system, the participants did not expect a stronger outcome on compound trials, and blocking was not observed. The results were partially replicated in Experiment 2, in which this pattern was found when the cues were tested for the second time. This evidence supports the claim that prior knowledge about the nature of causal relations can affect human causal learning. In addition, the fact that we did not manipulate causal assumptions through pretraining renders the results hard to account for with associative theories of learning.
... Latent inhibition has been shown in honeybees (Abramson and Bitterman, 1986;Chandra et al., 2000Chandra et al., , 2010Sandoz et al., 2000;Ferguson et al., 2001;Fernández et al., 2009;Fernandez et al., 2012), mollusks (Loy et al., 2006), fish (Mitchell et al., 2011), goats (Lubow and Moore, 1959), and rats (Ackil et al., 1969;Boughner and Papini, 2006). Overshadowing and blocking have been observed in flatworms (Prados et al., 2012), honeybees (Couvillon and Bitterman, 1989;Smith and Cobey, 1994;Couvillon et al., 1997;Smith, 1997), mollusks (Sahley et al., 1981;Colwill et al., 1988;Loy et al., 2006;Acebes et al., 2009), rats (Kamin, 1968;Prados et al., 2013), humans (Arcediano et al., 1997;Prados et al., 2013), rabbits (Merchant and Moore, 1973), and monkeys (Cook and Mineka, 1987). Second order conditioning has been observed in mollusks (Hawkins et al., 1998;Loy et al., 2006), rats (Lay et al., 2018), and monkeys (Cook and Mineka, 1987). ...
Article
Full-text available
This paper presents 13 hypotheses regarding the specific behavioral abilities that emerged at key milestones during the 600-million-year phylogenetic history from early bilaterians to extant humans. The behavioral, intellectual, and cognitive faculties of humans are complex and varied: we have abilities as diverse as map-based navigation, theory of mind, counterfactual learning, episodic memory, and language. But these faculties, which emerge from the complex human brain, are likely to have evolved from simpler prototypes in the simpler brains of our ancestors. Understanding the order in which behavioral abilities evolved can shed light on how and why our brains evolved. To propose these hypotheses, I review the available data from comparative psychology and evolutionary neuroscience.
... The critical finding in Arcediano et al.'s study was that humans showed increasing suppression of ongoing responding in the presence of the CSs that predicted the US, but not in the presence of the CSs that predicted the absence of the US. This task has also been shown to be a reliable preparation in the study of other wellknown effects, such as traditional (i.e., compounded) forward blocking (Arcediano, Matute, & Miller, 1997). In the present research, we used this preparation to assess whether individually trained CSs would compete in coming to suppress ongoing responding. ...
Article
Full-text available
Most associative theories have assumed that stimulus competition occurs only between conditioned stimuli (CSs) that are trained in compound. The present research investigated the possibility of competition between two CSs that were individually paired to the same unconditioned stimulus (US). We used human subjects in an anticipatory suppression analogue to Pavlovian conditioning. Experiment 1 showed that X+ training followed by A+ training resulted in impaired responding to X. This did not occur when A+ training preceded X+ training. Experiment 2 replicated the basic effect and showed that it did not occur when the Phase 2 training consisted of A− instead of A+ nor when the A+ pairings occurred in a second context. Experiment 3 showed that A+ pairings occurring in a second context could still produce the effect when X was tested in the context in which the A+ pairings had occurred, but not when X was tested in a context different from that used for A+ training. Collectively, these results suggest that individually trained CSs may compete with each other when one of those CSs is more strongly activated by the test context than the other one.
... Kamin, 1969;Kaye & Pearce, 1984;Miller & Matute, 1996) and human studies (e.g. Arcediano, Matute, & Miller, 1997;Shanks, 1985;Williams, Sagness, & McPhee, 1994). ...
Chapter
Full-text available
... A potentially important factor in training two-element configurations is the programmed order of the stimuli. Researchers used either a consistent order of presentation (e.g., Chapman, 1991; Chapman & Robbins, 1990; Williams, 1995; Williams, Sagness, & McPhee, 1994) or a counterbalanced order (e.g., Arcediano, Matute, & Miller, 1997; Wasserman & Berglan, 1998; Young et al., 2000), or they did not include sufficient detail to determine the method used. Although models of predictive learning have ignored the possible role of order, its effects may be important and measurable. ...
Article
Full-text available
The authors empirically tested the similarity metrics underlying 2 predictive-learning theories: J. K. Kruschke's (1992) attention learning covering map and J. M. Pearce's (1987, 1994) configural models. In Experiment 1, participants concurrently learned 3 types of discriminations: simple (A- vs. B+), common cue (XC- vs. XD+), and compound (YE- vs. ZF+). Accuracy was ordered: simple > compound > common cue. Neither model anticipated this ordering. In Experiment 2, cue order in 2-element configurations was either inconsistent (e.g., YE and EY) as in Experiment 1 or consistent (e.g., EY throughout). Although accuracy differences were smaller under consistent ordering, the relative difficulty of the tasks was the same as in Experiment 1. In Experiment 3, common cue and compound discriminations were tested in different participants to determine whether the ordering of difficulty in Experiments 1 and 2 was caused by differential generalization mediated by the number of elements; the ordering was the same as in Experiments 1 and 2. These results suggest the need for differential attention to event presence and absence and to mechanisms that incorporate limited attentional capacity.
... Here, the nature of the associative learning was inferred from nonverbal behavior of the participants in the presence of the cue. This method also has proven to be a useful preparation for the study of many Pavlovian phenomena, including cue competition and retroactive interference (Arcedanio et al., 1997;Matute and Pineño, 1998), and it has the benefit of reducing the effects of introspection that presumably underlies ratings. Molet et al. (2006) recently used a similar technique for the study of conditioned avoidance. ...
Article
Full-text available
Studies of human associative learning have often used causal/predictive learning preparations in which participants decide whether or not a first event is effective in causing or predicting a second event (i.e., an outcome). Those preparations have proved successful in replicating many Pavlovian phenomena. In the present paper we tested a novel associative learning preparation in which visually presented letters were paired with a visual outcome. Reaction times (RTs) were recorded to assess associative strength between specific cues and the outcome. Combining two different dependent variables (RTs and type of response given), we propose a rule for evaluating the associative strength between two events. The preparation and the data transformation rule were successful in producing several Pavlovian phenomena including excitatory acquisition, extinction, overshadowing, and latent inhibition, as well as established summation effects. Advantages and limitations of this new preparation based on the use of RT are discussed.
... The game was conceptually the same as that of Arcediano et al. (1996), which was used by Neumann (2006Neumann ( , 2007 and Havermans et al. (2005) to demonstrate recovery effects with changes in context. The versions of the game used by Neumann and Havermans et al. have demonstrated blocking (e.g., Arcediano, Matute, & Miller, 1997), and the version used here has demonstrated latent inhibition (Nelson & Sanjuan, 2006) and perceptual learning (Nelson & Sanjuan, 2008). Thus, it is a procedure that appears to involve basic associative processes and is not idiosyncratic to demonstrating the phenomenon at hand. ...
Article
Full-text available
Two experiments with human participants are presented that differentiate renewal from other behavioral effects that can produce a response after extinction. Participants played a video game and learned to suppress their behavior when sensor stimuli predicted an attack. Contexts (A, B, & C) were provided by fictitious galaxies where the game play took place. In Experiment 1, participants who received conditioning in A, extinction in B, and testing in A showed some context specificity of conditioning during extinction and a recovery of suppression on test. Experiment 2 demonstrated recovery of extinguished responding when participants were conditioned in A, extinguished in B, and tested in C, a third, neutral context. The experiment also demonstrated that the context of extinction did not control performance by becoming inhibitory. Results are discussed in terms of mechanisms that can produce a response recovery after extinction. The experiments demonstrated a renewal effect: a response recovery that was not attributable to the contexts acting as simple conditioned stimuli and is the first work with human participants to conclusively do so.
... In fact, the preparation has already proven its worth for investigating a diverse array of learning phenomena. So far, Martians has been successfully used to investigate blocking (Arcediano, Matute, & Miller, 1997) and other forms of cue competition (Matute & Pineño, 1998), simultaneous and sequential feature positive discriminations (Baeyens et al., 2001), simultaneous and sequential feature negative discriminations (Baeyens et al., 2004), extinction, renewal, and reinstatement of modulation (Baeyens et al., 2005;Fonteyne & Baeyens, 2009;Franssen, Gillard, Dirikx, van Vooren, & Baeyens, 2009), contextual modulation and extinction (Havermans, Keuker, Lataster, & Jansen, 2005), the influence of unpredictability-induced context conditioning on subsequent learning to a discrete cue (Meulders, Vervliet, Vansteenwegen, Hermans, & Baeyens, 2009), cue competition effects after elementary training (Lipp & Dal Santo, 2002), and consolidation of the CS-US association through mental rehearsal (Joos, Vansteenwegen, & Hermans, 2008). Outside learning psychology, the preparation could also be used, for example, to investigate hypotheses concerning avoidance mechanisms, such as a simple game-oriented filler task; or it could simply be used as a means of presenting electrical shocks. ...
Article
MartiansV2 is both a language syntax in which experiments can be written and an implementation of this syntax in a runtime application that, when fed a valid experiment text file, will execute the given experiment. It is based on the original Martians preparation, which has proven a valuable tool for assessing human online-conditioned suppression performance through research on a wide array of learning phenomena. This article can be read as a manual, both for using the Martians paradigm in general and for getting started with MartiansV2.
... Given that blocking and other cue competition effects have been widely observed in animal classical conditioning (Kamin, 1968; Wagner, Logan, Haberlandt, & Price, 1968), initial demonstrations of these effects in human contingency learning were taken as an evidence supporting the idea that cue competition in contingency learning is based on the same low-level associative mechanisms that were invoked to account for classical conditioning phenomena in animal research (Arcediano, Matute, & Miller, 1997; Chapman & Robbins, 1990; Dickinson et al., 1984; Price & Yates, 1993; Wasserman, 1990). However, recent experiments suggest that, contrary to this view, blocking in human contingency learning is based on higher-order cognitive processes related to causal reasoning (De Houwer, Beckers, & Glautier, 2002; Lovibond, Been, Mitchell, Bouton, & Augmentation under time-pressure 3 Frohart, 2003; Waldmann & Holyoak, 1992; for a recent review, see De Houwer, 2009). ...
Article
Recent research suggests that cue competition effects in human contingency learning, such as blocking, are due to higher-order cognitive processes. Moreover, some experimental reports suggest that the effect opposite to blocking, augmentation, could occur in experimental preparations that preclude the intervention of reasoning mechanisms. In the present research, we tested this hypothesis by investigating cue interaction effects in an experimental task in which participants had to enter their responses under time pressure. The results show that under these conditions, augmentation, instead of blocking, is observed.
... In summary, the results found in these experiments seem to be better explained by a retrieval framework of learning (Bouton, 1993) than by standard associative models. They add to the effects largely studied in nonhuman animal literature that have been replicated in humans, such the effects of time and context changes upon retrieval of the information (v.g., , generalization (see Bouton et al., 1999a;1999b;Riccio, Richardson & Ebner, 1984;, blocking (v.g., Arcediano, Matute & Miller, 1997;Miller & Matute, 1996), and learned helplessness (v.g., Matute, 1994;Maldonado, Martos & Ramírez, 1989;Ramírez, Maldonado & Martos, 1992) among many others. ...
Article
Full-text available
... This has received closest scrutiny not only in the study of sign-tracking (e.g., Akins, 1996;Brown, 1993;Hearst and Jenkins, 1974;Kaplan and Hearst, 1982;Rescorla, 1982), but also in the direct attribution of causal status, both by pigeons (e.g., Killeen, 1981) and humans (Allan and Tangen, 2005;De Houwer and Beckers, 2002). Events that intervene between a possible cause and effect, or are favored by priors, are attributed primary causal status; in like manner events that come between a stimulus and reinforcer, and those with prior conditioning strength, usurp the conditioning from other stimuli-the classic blocking and overshadowing effects (Arcediano and Matute, 1997;Khallad and Moore, 1996;Rodrigo et al., 1997;Williams, 1975;Williams and Lolordo, 1995). Spatial contiguity between the stimulus and reinforcer (Ellins and von Kluge, 1990;Kushnir and Gopnik, 2007;Silva et al., 1992), and between the stimulus and response in operant conditioning (Rumbaugh et al., 1989), are also important both for conditioning, and for our inferences concerning causality. ...
Article
Full-text available
Four experiments measured pigeons' pecking at a small touch-screen image (the CS) that moved towards or away from a source of food (the US). The image's effectiveness as a CS was dependent on its motion, direction, and distance relative to the US. Pecking to the CS increased with proximity to the US when the CS moved towards the US (Experiment 1). This held true even when a departing CS signalled a US of greater magnitude (Experiment 2). Response rates to stationary stimuli were greater the closer they were to the hopper; but rate was less than when the same spot was part of a motion towards food, and greater than when it was part of a motion away (Experiment 3). The rate of responding in all three cases (motion towards, stationary, motion away) decreased exponentially with distance from the hopper. The distance and motion effects observed under these Pavlovian contingencies were different when pecking to the spot was required for reinforcement (Experiment 4).
... In summary, the results found in these experiments seem to be better explained by a retrieval framework of learning (Bouton, 1993) than by standard associative models. They add to the effects largely studied in nonhuman animal literature that have been replicated in humans, such the effects of time and context changes upon retrieval of the information (v.g., , generalization (see Bouton et al., 1999a;1999b;Riccio, Richardson & Ebner, 1984;, blocking (v.g., Arcediano, Matute & Miller, 1997;Miller & Matute, 1996), and learned helplessness (v.g., Matute, 1994;Maldonado, Martos & Ramírez, 1989;Ramírez, Maldonado & Martos, 1992) among many others. ...
... Recent developments in the study of human learning from a classical conditioning paradigm are focusing in the use of traditional experimental procedures to study complex human behavior (Walther, Nagengast & Trasselli, 2005; Rescorla, 1988). The blocking effect for example, has been examined in studies of perceptual responding (Arcediano, Matute & Miller, 1997), spatial orientation (Wilson & Alexander, 2008), the acquisition of reading and writing repertories (Didden, Prinsen & Sigafoos, 2000; Singh & Solman, 1990), stimulus class acquisition (Delgado & Medina, In press; Rehfeldt, Dixon, Hayes & Steele, 1998), and causal learning (see Shanks, 2010 for a review). The purpose of this study is to identify the conditions under which people make causality judgments in an ambiguous situation where an event may have two possible causes. ...
Article
This study examines if the blocking effect paradigm predicts causal judgments when consequences of events vary in valence and magnitude. The procedure consists on presenting participants with reports describing the positive or negative effects produced by different substances, when these are consumed either separately or simultaneously with others. Two groups of participants were exposed to high and low magnitude consequences, respectively. The extent to which behavior with respect to causal judgments is consistent with the predictions of the blocking effect was evaluated in in both groups using two types of questions. One of them asked whether or not substance X produced the effect, while the other one asked about the probability of substance X producing the effect. Differences in causal judgments as a product of logical or intuitive reasoning were examined. Even though the blocking effect was not observed, a significant interaction was obtained between the factors valence and experimental condition (blocking and control). Findings are discussed in terms of the differences between associative learning in humans and in non-human animals, and in terms of the theoretical differences between evaluative conditioning and predictive or causal conditioning.
... The method has been used to demonstrate associative learning phenomena such as latent-inhibition (Nelson & Sanjuan, 2006). Nearly identical methods have been used to demonstrate "blocking" (Arcediano, Matute, & Miller, 1997), recovery of extinguished responding following a context switch (e.g., , and occasion setting (e.g., Baeyens et al. 2004;. Thus, the method is not one that is largely isolated to demonstrating perceptual learning as the tasks developed by Lavis and Mitchell 2006;Mitchell, Kadib et al., 2008; could be considered. ...
Article
Full-text available
The present experiment demonstrated a “perceptual learning” effect found in the animal literature with human participants. The common finding in animal work is that intermixed exposures to two stimuli prior to conditioning facilitates their subsequent discrimination on a generalization test more than the same amount of exposure to the stimuli in a blocked arrangement. The method was a suppression task implemented in a video game. Participants learned to suppress a baseline response (mouse clicking) when a colored sensor (i.e., CS) predicted an attack (i.e., US). First, prior to conditioning, they received either intermixed pre-exposures to two sensor CSs, blocked preexposures, no pre-exposures, or pre-exposure to the individual visual elements of the CSs. Second, in conditioning, one of the sensor CSs was paired with an attack US. Finally, generalization of suppression to the other sensor CS was assessed. Pre-exposures to the sensor CSs reduced generalization relative to no-exposure at all, with intermixed pre-exposures producing the greatest reduction in generalization. The importance of the present work is that it reduces the possible idiosyncrasy of existing results with humans that used evaluative-conditioning methods by demonstrating the effect with a method that has been used to reproduce a variety of associative-learning phenomena and is easily amenable to associative-learning explanations
... The surprising result is that, even though the contingency and priority relationship between the second stimulus and the outcome is strong, an association between the second stimulus and the outcome does not develop. This observation has been subsequently replicated in all manner of species, including pigeons (Good and Macphail, 1994), mollusks (Sahley et al., 1981), honeybees (Couvillon et al., 1997), and humans (Arcediano et al., 1997). ...
... This shows that the subject learned that stimulus B was not useful, and hence disregards their attention to it in the upcoming events (Wagner, 1970;Mackintosh, 1975;Rescorla & Wagner, 1972). Studied in humans in Chapman and Robbins (1990), Arcediano et al. (1997), and Kruschke and Blair (2000) among others, our work differs from these approaches in that we never introduce a stage were a feature A is intentionally exposed in absence to B, in order to guide the attention of the participant. ...
Article
Full-text available
When people seek to understand concepts from an incomplete set of examples and counterexamples, there is usually an exponentially large number of classification rules that can correctly classify the observed data, depending on which features of the examples are used to construct these rules. A mechanistic approximation of human concept-learning should help to explain how humans prefer some rules over others when there are many that can be used to correctly classify the observed data. Here, we exploit the tools of propositional logic to develop an experimental framework that controls the minimal rules that are simultaneously consistent with the presented examples. For example, our framework allows us to present participants with concepts consistent with a disjunction and also with a conjunction, depending on which features are used to build the rule. Similarly, it allows us to present concepts that are simultaneously consistent with two or more rules of different complexity and using different features. Importantly, our framework fully controls which minimal rules compete to explain the examples and is able to recover the features used by the participant to build the classification rule, without relying on supplementary attention-tracking mechanisms (e.g. eye-tracking). We exploit our framework in an experiment with a sequence of such competitive trials, illustrating the emergence of various transfer effects that bias participants’ prior attention to specific sets of features during learning.
... By describing potential mechanisms for the interaction between learning and attention, the Mackintosh (1975) and Pearce and Hall (1980) theories have been able to provide accounts for a wide range of phenomena. The original impetus for the theories was to account for selective learning effects, often referred to as cue competition effects, such as blocking (Arcediano, Matute, & Miller, 1997;Kamin, 1969) and overshadowing (Pavlov, 1927;Prados, 2011) in which animals and humans learn about some cues but not others. In addition they provide accounts of the effect of latent inhibition in which preexposure to a cue retards acquisition of learning (Lubow & Moore, 1959), a procedure widely used as a test of selective attention in the assessment of the cognitive impairments in psychopathology (Lubow, 1997). ...
Article
... Blocking has been well documented, found not only in the original between-subjects design (Kamin, 1968(Kamin, , 1969 but also in a withinsubject design (Rescorla, 2000). It has also been found in appetitive (Dickinson, Hall, & Mackintosh, 1976;Holland, 1985;Rescorla, 2001;vom Saal & Jenkins, 1970) and toxiphobia conditioning procedures (Best, Brown, & Sowell, 1984;Westbrook & Brookes, 1988;Willner, 1978), and in subjects from a range of species, including honeybees (Cheng & Spetch, 2001;Guerrieri, Lachnit, Gerber, & Giurfa, 2005), snails, and other mollusks (Acebes, Solar, Carnero, & Loy, 2009;Mackintosh & Honig, 1970;Prados et al., 2013;Sahley, Rudy, & Gelperin, 1981), pigeons (Leyland & Mackintosh, 1978;Williams, 1975), rabbits (Kehoe, Schreurs, & Amodei, 1981;Marchant & Moore, 1973), monkeys, and humans (Arcediano, Mutate, & Miller, 1997;Beauchamp, Gluck, Fouty, & Lewis, 1991;Le Pelley, Beesley, & Griffiths, 2014;Livesey & Boakes, 2004;Mitchell & Lovibond, 2002). ...
Article
This series of experiments used rats to examine changes in behavioral control when stimuli with different associative histories are conditioned in compound. The initial experiments used blocking designs. Experiment 1 provided a within-subject demonstration of blocking, and Experiment 2 used the compound test procedure to show that, when a novel stimulus, X, is conditioned in compound with an already conditioned stimulus (CS), A, these audiovisual compound stimulus (AX)+ conditioning trials produce a greater increase in behavioral control for X than A. Experiment 3 showed that, when the blocked X is subject to further conditioning in compound with the blocking A (achieved by increasing the shock intensity on AX-shock trials), the compound trials again produce a greater increase in behavioral control for X than A. Finally, Experiment 4 showed that the unequal change in behavioral control for X and A was because of the difference in their training histories and not the test procedure. The overall pattern of results is consistent with the proposal (Rescorla, 2001) that associative change is regulated by the product of common and individual error terms rather than by common (Pearce & Hall, 1980; Rescorla & Wagner, 1972) or individual (Mackintosh, 1975) error terms. The pattern is also consistent with comparator theory (e.g., Miller & Matzel, 1988), which holds that the level of responding to a target is regulated by the strength of its comparator stimuli established in training. (PsycINFO Database Record
... The previous pairings of CS1 and the US is then said to have blocked the establishment of stimulus control by CS2. Blocking in classical conditioning has been shown in experiments with rats (e.g., Blaisdell, Gunther, & Miller, 1999;Cheatle & Rudy, 1978;Fowler, Goodman, & DeVito, 1977;Mackintosh, 1975;Taylor, Joseph, Balsam, & Bitterman, 2008), pigeons (e.g., Mackintosh & Honig, 1970;Palmer, 1988;Williams, 1975), rabbits (e.g., Stickney & Donahoe, 1983), and humans (Arcediano, Matute, & Miller, 1997;Bergen, 2002;Delgado, 2016;Kimmel & Bevill, 1991;Martin & Levey, 1991). ...
Article
Full-text available
The present study aimed to investigate the blocking of stimulus control in three children with autism. We used a go/no-go procedure in a standard blocking paradigm. In Phase 1, we established one of two sounds or colored squares as a discriminative stimulus for touching a tablet screen. In Phase 2, a colored square was added to the sound or a sound was added to the colored square in a stimulus compound. The discrimination training continued as in Phase 1. We subsequently tested discriminative control by each of the single stimuli separately and by the compounds. Finally, after testing with no programmed consequences, we reestablished the original discrimination and replicated the test of stimulus control. The results support previous experiments by demonstrating that the establishment of discriminative control by a second stimulus by adding it to a previously established discriminative stimulus in a compound was blocked by the earlier discrimination training in all three participants. We discuss procedural details that may be critical to avoid the blocking of stimulus control in the applied field, particularly with respect to the acquisition of skills that involve multiple stimuli, such as joint attention, social referencing, and bidirectional naming.
... Blocking has been studied in several vertebrates such as pigeons (Good and Macphail 1994), rats (Kamin 1968;Batsell 1996;Batsell and Batson 1999;Wiltrout et al. 2003), rabbits (Solomon 1977;Giftakis and Tait 1998;Allen et al. 2002), rhesus monkeys (Beauchamp et al. 1991;Waelti et al. 2001), and humans (Miller and Matute 1996;Arcediano et al 1997). In invertebrates, research on blocking has been conducted in the mollusks Limax (Sahley et al. 1981) and Hermissenda (Rogers and Matzel 1996), in the fruit fly Drosophila melanogaster and in the honeybee Apis mellifera. ...
Thesis
Full-text available
"A comprehensive study of olfactory perception in the honey bee Apis mellifera: behaviour and calcium imaging" We studied how olfactory information is processed by the nervous system of an invertebrate, the honey bee Apis mellifera. For that, we combined behavioural and calcium imaging studies. In the behavioural aspect, we used the olfactory conditioning of the proboscis extension, in which a harnessed honey bee learns to associate an odour to a sucrose reward. 1) We identified the structural parameters of a molecule, which serve to determine the similarity or the difference among odours. Chemical functional group and carbon chain length are two parameters that define the dimensions of an olfactory perceptual space that we could construct after having conditioned 2048 bees using a 16 x 16 odour matrix. We then correlated the behavioural similarity measures obtained in this space to the physiological similarity measures obtained by neural activity recording by calcium imaging of the antennal lobe, the first processing centre of the olfactory information in the insect brain. We thus showed that the correlation between these two similarity measures was very high, which indicates that perception and neural activity are strongly linked in the olfaction of the honey bee. 2) We then concentrated on a learning phenomenon: "blocking". Blocking occurs when previous learning on a stimulus A impairs ('blocks') subsequent learning of a stimulus B, as A and B are presented together. Blocking constitutes an interesting subject for studying olfaction, since interaction within the olfactory mixture AB could explain the lack of learning of AB. Apart from this, similarity between odours was postulated to be crucial for the manifestation of blocking. By means of conditioning the proboscis extension, we analysed different odour combinations varying in their similarity and tested 1200 bees using the blocking protocol. We could thus demonstrate that blocking is neither a consistent phenomenon nor depends on odour similarity. 3) We studied the effect of exposition to alarm pheromones Isopentyl acetate (IPA) and2-hetptanone (2-H) on an appetitive response, the proboscis extension, and on an aversive response, the stinging reflex. Harnessed bees exposed to different doses of IPA or 2-H were stimulated either with sucrose solution, to elicit the extension of the proboscis, or with en electric shock, to elicit the stinging reflex. Our results show that IPA and 2-H have different functions. While IPA provokes an increase in the occurrence of the stinging reflex, 2-H does not. Higher doses of IPA decreased the stinging reflex as an effect of analgesia induced by the activation of an opioid system in stress situations. So, IPA seems more specifically related to the defensive function than 2-H, which could serve as deterrent mark on already visited flowers in a foraging context. 4) In the neurobiological aspect, we applied calcium imaging in order to study neural activity modifications in the antennal lobe, after an absolute conditioning, in which only one odour was reinforced. We did not observe any changes in the overall activity induced by the learnt odours. Although the number of individuals included in this part of our work still remains small, it looks as if absolute conditioning induces little modifications of the neural representation of odours and it would not have any contrasting effect regarding other odours. Thus, our present work shows that certain fundamental principles of olfactory information processing by the nervous system could be unravelled through the appliance of a combination of behavioural and calcium imaging studies.
... More extensive research has been performed in human causality judgments. Cell 1-type interference has been observed in blocking (e.g., Arcediano, Matute, & Miller, 1997;Arcediano, Escobar, & Matute, 2001) and overshadowing (e.g., Price & Yates, 1993). Cell 2-type interference has been observed in selected occasions (e.g., Matute, Arcediano, & Miller, 1996;Shanks & López, 1996; but see e.g., Waldmann, 2000;Waldmann & Holyoak, 1992). ...
... The method has been used to demonstrate associative learning phenomena such as latent-inhibition (Nelson & Sanjuan, 2006). Nearly identical methods have been used to demonstrate "blocking" (Arcediano, Matute, & Miller, 1997), recovery of extinguished responding following a context switch (e.g., , and occasion setting (e.g., Baeyens et al. 2004;. Thus, the method is not one that is largely isolated to demonstrating perceptual learning as the tasks developed by Lavis and Mitchell 2006;Mitchell, Kadib et al., 2008; could be considered. ...
Article
Full-text available
The present experiment demonstrated a “perceptual learning” effect found in the animal literature with human participants. The common finding in animal work is that intermixed exposures to two stimuli prior to conditioning facilitates their subsequent discrimination on a generalization test more than the same amount of exposure to the stimuli in a blocked arrangement. The method was a suppression task implemented in a video game. Participants learned to suppress a baseline response (mouse clicking) when a colored sensor (i.e., CS) predicted an attack (i.e., US). First, prior to conditioning, they received either intermixed pre-exposures to two sensor CSs, blocked preexposures, no pre-exposures, or pre-exposure to the individual visual elements of the CSs. Second, in conditioning, one of the sensor CSs was paired with an attack US. Finally, generalization of suppression to the other sensor CS was assessed. Pre-exposures to the sensor CSs reduced generalization relative to no-exposure at all, with intermixed pre-exposures producing the greatest reduction in generalization. The importance of the present work is that it reduces the possible idiosyncrasy of existing results with humans that used evaluative-conditioning methods by demonstrating the effect with a method that has been used to reproduce a variety of associative learning phenomena and is easily amenable to associative-learning explanations.
... Sessions ces résultats, Rescorla conclu que l'appariement contigu entre un SC et un SI n'était pas la variable déterminante pour que le processus Pavlovien ait lieu, mais plutôt, ce processus dépendrait de la relation prédictive agencée entre le SC et le SI, mesurée dans ces expériences par la contingence C. Les résultats obtenus à la même période par Kamin (1968Kamin ( , 1969 Kamin (1968Kamin ( , 1969 La mise en évidence du phénomène de blocage s'inscrit dans les expériences réalisées sur les stimuli dits composés. Le premier principal effet mis en évidence sur les stimuli composés est certainement celui d'overshadowing (Pavlov, 1927 Le phénomène fut originellement mis en évidence par Kamin (1968Kamin ( , 1969 avec des rats placés dans une procédure de peur conditionnée avec ratio de suppression, mais le phénomène fut répliqué à d'autres situations et notamment chez l'humain, comme par exemple dans une tâche de conditionnement de fermeture de la paupière (Martin et Levey, 1991) ou dans une tâche de jeu vidéo (Arcediano et al., 1997 'Egger et Miller (1962, 1963, Rescorla (1966Rescorla ( , 1967Rescorla ( , 1968, et enfin Kamin (1969), à une période où des alternatives aux propositions S -R émergeaient et où on commençait à suggérer l'emploi de concepts relatifs à la notion d'information pour décrire les phénomènes associatifs (e.g. Berlyne, 1957), entraînèrent un abandon progressif de cette proposition et l'apparition, en parallèle, de l'Hypothèse de l'Information. ...
Thesis
Full-text available
Chez l’espèce humaine comme pour de nombreuses autres espèces animales, lorsque des stimuli environnementaux précèdent de façon régulière la présentation d’événements importants pour un individu, ces stimuli vont acquérir sous certaines conditions la capacité à évoquer des comportements dits d’anticipation. Cette capacité est considérée par de nombreux auteurs comme ayant une haute valeur adaptative, favorisant le contact avec des événements appétitifs et permettant l’évitement d’événements aversifs. Ces dernières décennies, deschercheurs ont initié un rapprochement entre le phénomène d’anticipation et le conditionnement Pavlovien. Ce rapprochement repose à la fois sur une similarité dans les caractéristiques des événements mis en jeux mais surtout sur de nombreux effets et phénomènes semblables, amenant ces auteurs à considérer que les comportements ditsd’anticipation, d’une façon générale, reposeraient sur le processus Pavlovien. Leconditionnement Pavlovien offre une littérature extrêmement riche dont l’une des principalesquestions de recherche concerne le problème des conditions à l’apparition du processus.Parmi les hypothèses existantes, l’Hypothèse de l’Information est sans aucun doute l’une desplus importantes par son influence. Selon cette hypothèse, un apprentissage associatifPavlovien n’aura lieu que lorsqu’un événement important sera présenté de façon inattendu à un sujet, et l’apprentissage, ou les associations apprises, ne porteront que sur des stimuli prédictifs de l’événement important (i.e. permettant son anticipation). A travers deux expériences appliquant une procédure de conditionnement rétrograde à une procédure de renforcement conditionné, nous avons cherché à tester les propositions faites par cette hypothèse. Nos résultats vont directement à l’encontre de ces propositions et vont au contraire dans le sens de deux autres propositions théoriques faites sur le conditionnement Pavlovien,illustrées par le modèle SOP et l’Hypothèse du Codage Temporel. Ces deux propositions sont testées au sein d’une troisième et dernière expérience, dont les implications pour ces modèles comme pour la conceptualisation du conditionnement Pavlovien et de l’anticipation de façon générale sont discutées.
... Eyeblink conditioning in particular involves the cerebellum (Jirenhed et al., 2007;McCormick and Thompson, 1984). In addition, additional CS-US combinations that include, for example, the presentation of the CS before the CS-US association (latent inhibition) or involve more complex CS-US associations as in blocking designs (e.g., Arcediano et al., 1997) may be used to uncover dysfunctional learning processes that reflect, for example, insufficient inhibitory processes. Dysfunctions in learning processes of these latter types involve differing neural systems and thus translate into different mental disorder symptoms. ...
Article
Full-text available
The Research Domain Criteria Project suggests to base the classification of mental disorders on dimensions of observable behavior and neurobiological measures of these functions rather than on symptom-based descriptive categorical diagnoses. We suggest a mechanistic approach that focuses on the role of learning as a core mechanism that can be studied in animals and humans. We review human studies on neurobiological, psychophysiological, and behavioral correlates of pavlovian associative learning and delineate commonalities and differences across disorders. In addition to the hedonic value, the learning phase (i.e. habituation, acquisition, extinction, extinction recall), the role of stimulus properties (i.e., cue and context), and event timing (e.g. delay and trace conditioning) were considered. We address how core behavioral and psychophysiological indicators of conditioning, such as contingency ratings and skin conductance responses or startle modulation, respectively, are altered. We also discuss plastic changes in core brain regions and the interaction of brain regions in inhibitory and excitatory circuits. We also address the translation of findings pertaining to classical conditioning and its affiliated processes into the development of new behavioral and pharmacological treatments for mental disorders, and discuss productive avenues for future studies. Copyright © 2015. Published by Elsevier B.V.
... When forward blocking is used in experiments on human causal learning, the blocking effect is sometimes observed, but its magnitude is more heterogeneous. Some studies have reported robust forward blocking effects in humans (e.g., Arcediano, Matute, & Miller, 1997;Dickinson et al., 1984;Shanks, 1985), leading many investigators to infer that human causal learning may be based on the same associative processes argued to underlie animal conditioning. However, other studies of human causal learning have yielded blocking effects that were relatively weak (i.e., partial rather than complete blocking), or even failures to obtain this effect (Glautier, 2002;Lovibond, Siddle, & Bond, 1988;Vandorpe & De Houwer, 2005;Waldmann & Holyoak, 1992). ...
Article
Full-text available
Two key research issues in the field of causal learning are how people acquire causal knowledge when observing data that are presented sequentially, and the level of abstraction at which learning takes place. Does sequential causal learning solely involve the acquisition of specific cause-effect links, or do learners also acquire knowledge about abstract causal constraints? Recent empirical studies have revealed that experience with one set of causal cues can dramatically alter subsequent learning and performance with entirely different cues, suggesting that learning involves abstract transfer, and such transfer effects involve sequential presentation of distinct sets of causal cues. It has been demonstrated that pre-training (or even post-training) can modulate classic causal learning phenomena such as forward and backward blocking. To account for these effects, we propose a Bayesian theory of sequential causal learning. The theory assumes that humans are able to consider and use several alternative causal generative models, each instantiating a different causal integration rule. Model selection is used to decide which integration rule to use in a given learning environment in order to infer causal knowledge from sequential data. Detailed computer simulations demonstrate that humans rely on the abstract characteristics of outcome variables (e.g., binary vs. continuous) to select a causal integration rule, which in turn alters causal learning in a variety of blocking and overshadowing paradigms. When the nature of the outcome variable is ambiguous, humans select the model that yields the best fit with the recent environment, and then apply it to subsequent learning tasks. Based on sequential patterns of cue-outcome co-occurrence, the theory can account for a range of phenomena in sequential causal learning, including various blocking effects, primacy effects in some experimental conditions, and apparently abstract transfer of causal knowledge.
Article
Full-text available
Consider $Z^f_t(u)=\int_0^{tu}f(N_s) ds$, $t>0$, $u\in[0,1]$, where $N=(N_t)_{t\in\mathbb{R}}$ is a normal process and $f$ is a measurable real-valued function satisfying $Ef(N_0)^2<\infty$ and $Ef(N_0)=0$. If the dependence is sufficiently weak Hariz [J. Multivariate Anal. 80 (2002) 191--216] showed that $Z_t^f/t^{1/2}$ converges in distribution to a multiple of standard Brownian motion as $t\to\infty$. If the dependence is sufficiently strong, then $Z_t/(EZ_t(1)^2)^{1/2}$ converges in distribution to a higher order Hermite process as $t\to\infty$ by a result by Taqqu [Wahrsch. Verw. Gebiete 50 (1979) 53--83]. When passing from weak to strong dependence, a unique situation encompassed by neither results is encountered. In this paper, we investigate this situation in detail and show that the limiting process is still a Brownian motion, but a nonstandard norming is required. We apply our result to some functionals of fractional Brownian motion which arise in time series. For all Hurst indices $H\in(0,1)$, we give their limiting distributions. In this context, we show that the known results are only applicable to $H<3/4$ and $H>3/4$, respectively, whereas our result covers $H=3/4$.
Article
Full-text available
Stimulus competition (e.g., blocking) has been observed between antecedent events (i.e., conditioned stimuli or potential causes), but recent evidence within the human causal learning literature suggests that it could also be obtained between subsequent events (i.e., unconditioned stimuli or potential effects). The present research tested this hypothesis with rat subjects. To avoid confounding the antecedent versus subsequent variable with the affective value of the events involved (i.e., unconditioned stimuli are ordinarily of greater affective value than conditioned stimuli), a preparation was used in which antecedent and subsequent events all lacked affective value during the blocking phases of the study. This was achieved through the use of sensory preconditioning. Blocking of subsequent events as well as antecedent events was observed. The challenge to most associative theories that is provided by blocking of subsequent events is discussed.
Article
Four experiments examine blocking of associative learning by human participants in a disease diagnosis procedure. The results indicate that after a cue is blocked, subsequent learning about the cue is attenuated. This attenuated learning after blocking is obtained for both standard blocking and for backward blocking. Attenuated learning after blocking cannot be accounted for by theories such as the Rescorla-Wagner model that rely on lack of learning about a redundant cue, nor can it be accounted for by extensions of the Rescorla-Wagner model designed to address backward blocking that encode absent cues with negative values. The results are predicted by the hypothesis that people learn not to attend to the blocked cue.
Article
Full-text available
Latent inhibition (attenuated responding to a signal due to signal-alone presentations preceding the signal-outcome pairings) and blocking (attenuated responding to Signal B due to Signal A being paired with the outcome prior to pairings of an AB compound with the outcome) are reportedly absent in acute schizophrenics. The common assumption that these phenomena reflect the normal functioning of attention and the observation that rats administered low doses of amphetamine show a similar disruption has resulted in the development of an animal model of attentional dysfunction in acute schizophrenia. Here, we selectively review the experimental and clinical literature concerning latent inhibition and blocking, their disruption in acute schizophrenia, and the current status of this model. We conclude that the construct validity of the model is compromised if latent inhibition and blocking are viewed in attentional terms because experimental data indicate both phenomena can be better understood in associative terms. We favor a framework in which disruption of latent inhibition and blocking in acute schizophrenics is viewed as an inability to compare and express stored representations (i.e. associative performance deficit). This change of perspective does not undermine the potential value of the model, but rather suggests that the nature of its validity should be reconsidered.
Article
Full-text available
In recent years, several studies of human predictive learning demonstrated better learning about outcomes that have previously been experienced as consistently predictable compared to outcomes previously experienced as less predictable, namely the outcome predictability effect. As this effect may have wide-reaching implications for current theories of associative learning, the present study aimed to examine the generality of the effect with a human goal-tracking paradigm, employing three different designs to manipulate the predictability of outcomes in an initial training phase. In contrast to the previous studies, learning in a subsequent phase, when every outcome was equally predictable by novel cues, was not reliably affected by the outcomes’ predictability in the first phase. This lack of an outcome predictability effect provides insights into the parameters of the effect and its underlying mechanisms.
Article
El fenómeno de bloqueo describe una circunstancia en la cual se impide o se dificulta el la transferencia de funciones entre eventos que se han presentado en una relación de contigüidad espacio-temporal. Desde una perspectiva teórica y empírica, el efecto bloqueo no debería predecirse en la adquisición de clases de estímulos aun cuando algunos de los estímulos de la misma clase se presenten simultáneamente. El presente estudio examina si la historia adicional de entrenamiento A-EI bien sea previa o posterior al entrenamiento con un estímulo muestra compuesto AX, es la variable crítica en la presentación del efecto bloqueo. Los desempeños obtenidos en las pruebas de bloqueo por los participantes de un grupo expuesto al procedimiento de bloqueo, un grupo expuesto al procedimiento de bloqueo invertido, y un grupo control, sugieren que el entrenamiento adicional con un solo elemento del compuesto no impide la inclusión de todos los estímulos dentro de la clase. Los casos en los que se observó el efecto bloqueo se interpretan en términos de tipos de percepciones elementales y configurales.
Article
Full-text available
Select literature regarding cue competition, the contents of learning, and retrieval processes is summarized to demonstrate parallels and differences between human and nonhuman associative learning. Competition phenomena such as blocking, overshadowing, and relative predictive validity are largely analogous in animal and human learning. In general, strong parallels are found in the associative structures established during learning, as well as in the basic phenomena associated with information retrieval. Some differences arise too, such as retrospective evaluation, which seems easier to observe in human than in nonhuman animals. However, the parallels are sufficient to indicate that the study of learning in animals continues to be relevant to human learning and memory.
Article
Both associative and rule-learning theories have been proposed to account for rat serial pattern learning, but individually they are unable to account for a variety of recent behavioral and psychobiological phenomena. The present study examined the role of rule learning versus discriminative learning in rat pattern learning using a classic associative phenomenon: blocking. Rats learned to press levers in an 8-lever circular array according to a rule-based serial pattern, 123-234-345-456-567-678-781-812, where digits indicate the correct lever in the array for each trial. Each pattern presentation contained a chunk with a final element violation, such as 454 instead of 456. Rats learned in a first phase that a noise signaled the violation chunk; then, a concurrent spatial cue was added in a second phase. A test with spatial cues alone showed that blocking occurred. The results suggest that associative learning mediated cuing of violation elements. Taken together with other behavioral and psychobiological evidence already reported in the literature implicating rule learning when rats learn this pattern in this paradigm, these results implicate multiple concurrent learning processes in rat serial pattern learning.
Article
Contemporary learning theories derive much of their explanatory power from the assumption that all stimuli presented vie for associative strength, the assumption of Shared Weight Space (SWS). Theories based on this assumption have proven successful in explaining many of the observed conditioning phenomena in animals. However, work with humans has proven more complex due to outside knowledge, biases, and heuristics (see, e.g., Chapman, 1991; Msetfi et al., 2005; Perales et al., 2004; Tversky & Kahneman, 1974; Viken et al., 2005; Waldmann, 2000 & 2001). The present series of experiments sought to test the assumption of SWS in a task that is less susceptible to the influence of "top-down" factors. An information processing task (i.e., the correlated flankers task) was used so that human participants were completing a central task (i.e., responding to the target) and were unaware as to the importance of the contingencies in the designs, yet were still exposed to them via the irrelevant information (i.e., flankers). Four compound conditioning phenomena were studied in order to test the assumption of SWS. Evidence for the simple predictions coming from SWS theories was mixed. However, a slightly more complex version of these theories can explain the entire pattern of data quite elegantly.
Article
Article
The blocking effect describes a circumstance which impedes function transfer among events that are part of a relation of spatiotemporal contiguity. However, theoretical and empirical evidence in stimulus class acquisition predicts that the blocking effect should not be observed even if some of the stimul11n the class are presented simultaneously as compound stimuli. The present study examines if additional A-EI training, whether prior or following training with a compound sample AX, constitutes a critical variable in the occurrence of the blocking effect. Performances in blocking tests by a group exposed to the blocking procedure, a group exposed to the backward blocking procedure and a control group were compared. Findings suggest that additional training with one member of the compound does not impede responding to all stimuli as members of the class. Instances where the blocking effect was observed are interpreted in terms of configural and elemental types of responding.
Article
Using a conditioned suppression task, we investigated simultaneous (XA−/A+) vs. sequential (X → A−/A+) Feature Negative (FN) discrimination learning in humans. We expected the simultaneous discrimination to result in X (or alternatively the XA configuration) becoming an inhibitor acting directly on the US, and the sequential discrimination in X becoming a negative occasion setter acting indirectly on the A–US link. After simultaneous FN training, X+ training completely abolished discriminative XA/A responding (Experiment 1), and X transferred inhibition to new targets B regardless of their training history (B+ or YB−/B+) (Experiment 2), suggesting X became a simple inhibitor. After sequential FN training, X showed the predicted selective transfer to a target B that also had been modulated (Y → B−/B+), not to a simple excitor (B+) (Experiment 4), but turning X into an excitor (X+) likewise disrupted discriminative X → A/A responding (Experiment 3). This suggests that X acquired a combination of modulatory and direct inhibitory properties, and that the joint contribution of both components is necessary for the suppression of the target-induced US activation.
Article
The authors propose that a multimodal classical conditioning model be considered when clinicians or clinical researchers study the etiology of fears and anxieties learned by human beings. They argue that fears can be built through the combined effects of direct, observed, and verbally presented classical conditioning trials. Multimodal classical conditioning is offered as an alternative to the three pathways to fear argument prominent in the human fear literature. In contrast to the three pathways position, the authors present theoretical arguments for why "learning by observation" and "learning through the receipt of verbal information" should be considered classical conditioning through observational and verbal modes. The paper includes a demonstration of how data, commonly collected in research on the three pathways to fear, would be studied differently using a multimodal classical conditioning perspective. Finally, the authors discuss implications for assessment, treatment, and prevention of learned fears in humans.
Thesis
La contingencia entre dos eventos, clave y outcome, es una pista fundamental para inferir relaciones causales en la mayoría de las situaciones. La evidencia experimental indica que tanto las personas como otros animales son capaces de adaptar su conducta a la contingencia, si bien se han documentado algunos sesgos. En concreto, el sesgo de densidad del outcome es la sobrestimación de la contingencia cuando la probabilidad de ocurrencia del outcome es elevada. En el presente trabajo, utilizamos una red neuronal auto-heteroasociativa para simular una tarea típica de aprendizaje de contingencia en humanos. Nuestras simulaciones demuestran que la red es capaz de discriminar satisfactoriamente entre distintos grados de contingencia, aunque no se observa evidencia del sesgo de densidad del outcome.
Article
Full-text available
The blocking effect describes a circumstance which impedes function transfer among events that are part of a relation of spatiotemporal contiguity. However, theoretical and empirical evidence in stimulus class acquisition predicts that the blocking effect should not be observed even if some of the stimuli in the class are presented simultaneously as compound stimuli. The present study examines if additional A-EI training, whether prior or following training with a compound sample AX, constitutes a critical variable in the occurrence of the blocking effect. Performances in blocking tests by a group exposed to the blocking procedure, a group exposed to the backward blocking procedure and a control group were compared. Findings suggest that additional training with one member of the compound does not impede responding to all stimuli as members of the class. Instances where the blocking effect was observed are interpreted in terms of configural and elemental types of responding.
Article
Full-text available
Review of the literature indicates that, according to theories of selective attention, learning about a stimulus depends on attending to that stimulus; this is represented in 2-stage models by saying that Ss switch in analyzers as well as learning stimulus-response associations. It is argued that this assumption, however, is equally well represented in a formal model by the incorporation of a stimulus-specific learning-rate parameter, a, into the equations describing changes in the associative strength of stimuli. Previous theories of selective attention have also assumed that (a) Ss learn to attend to and ignore relevant and irrelevant stimuli (i.e., that a may increase or decrease depending on the correlation of a stimulus with reinforcement); and (b) there is an inverse relationship between the probabilities of attending to different stimuli (i.e., that an increase in a to one stimulus is accompanied by a decrease in a to others). The first assumption has been used to explain the phenomena of acquired distinctiveness and dimensional transfer, the second to explain those of overshadowing and blocking. It is argued that although the first assumption is justified by the data, the second is not: Overshadowing and blocking are better explained by the choice of an appropriate rule for changing a, such that a decreases to stimuli that signal no change from the probability of reinforcement predicted by other stimuli. (65 ref) (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Article
Full-text available
Most studies of human contingency judgment have been based on the assumption that frequency information about one predictor is assessed in isolation of information about other predictors. Recent evidence, however, suggests that the judged predictive strength of one cue is influenced by the predictive strengths of other copresent cues. Two experiments demonstrate that stimuli with the same outcome contingencies may nonetheless have different predictive strengths as the result of cue interaction. The first experiment, in which a within-subject design was used, provides a demonstration of blocking. A stimulus presented in compound with a strong predictor was rated as less predictive than another stimulus that was presented in compound with a nonpredictive cue. In the second experiment, cue interactions in conditioned inhibition were examined. A stimulus gained negative predictive strength as the result of compound presentations with a positive predictor when the outcome was not presented. This negative predictor was compared with an otherwise analogous stimulus that was not presented in compound with a positive predictor. These results support the use of animal-conditioning models as accounts of human contingency learning.
Article
Full-text available
The Kamin blocking effect consists in impaired learning of an association between a conditioned stimulus (CS2) and an unconditioned stimulus (UCS) if CS2 is presented simultaneously with a different CS (CS1) already associated with the UCS. It is well established with animal but not human subjects. In the two experiments presented here, the effect was clearly demonstrated with UCS = a computer-presented yellow square, CS1 = a blue square and CS2 = a noise (Expt 1) or two smaller white squares (Expt 2). The Kamin effect has, by some theorists, been attributed to switching of attention away from CS2, which conveys only redundant information. If so, the size of the effect should co-vary with indices of selective attention commonly used with human subjects. As predicted, the blocking effect was found to be smaller in subjects who displayed a high degree of incidental learning in either of two tasks in which intentional vs. incidental learning corresponded to (1) words vs. word position, or (2) a target initial word letter vs. non-target initial letters. We report elsewhere that the blocking effect is absent in acute schizophrenics. In the present experiments, however, there was no systematic relation between any of four measures of psychoticism, or intelligence, and either the blocking effect or incidental learning.
Article
Full-text available
REPORTS 3 EXPERIMENTS, INVOLVING BOTH INSTRUMENTAL AND CLASSICAL CONDITIONING PROCEDURES IN RATS AND RABBITS. IN EACH CASE A PARTIALLY REINFORCED CUE WAS FOUND TO BE A LESS EFFECTIVE STIMULUS IN ISOLATION WHEN IT HAD BEEN EXPERIENCED AS A COMMON CUE IN COMPOUNDS CONTAINING ELEMENTS MORE HIGHLY CORRELATED WITH REINFORCEMENT, THAN WHEN IT HAD BEEN EXPERIENCED IN SIMILAR COMPOUNDS WHICH DID NOT CONTAIN SUCH ELEMENTS. THE FINDINGS ARE MORE READILY INTERPRETABLE IN TERMS OF THOSE THEORIES WHICH INCORPORATE A BASIC STIMULUS-SELECTION PROCESS, THAN IN TERMS OF SIMPLE CONDITIONING-EXTINCTION THEORY. (17 REF.) (PsycINFO Database Record (c) 2006 APA, all rights reserved).
Article
Full-text available
The research reported in this article replicated the well-established phenomenon of competition between causes (C) as well as the more controversial presence and absence of competition between effects (E). The test question was identified as a crucial factor leading to each outcome. Competition between causes was obtained when the test question asked about the probability of E given C, p(E/C), implicitly compared with the probability of E given some alternative cause, p(E/C'). competition between effects was obtained when the test question asked about p(C/E) implicitly compared with p(C/E'). Under these conditions, effects competed for diagnostic value just as causes competed for predictive value. Additionally, some conditions in which neither causes nor effects competed were identified. These results suggest a bidirectional and noncompetitive learning process, the contents of which can be used in different ways (competitively or noncompetitively and forward or backward) as a function of test demands.
Article
Full-text available
Conditioned suppression is a useful technique for assessing whether subjects have learned a CS-US association, but it is difficult to use in humans because of the need for an aversive US. The purpose of this research was to develop a non-aversive procedure that would produce suppression. Subjects learned to press the space bar of a computer as part of a video game, but they had to stop pressing whenever a visual US appeared, or they would lose points. In Experiment 1, we used an A+/B- discrimination design: The US always followed Stimulus A and never followed Stimulus B. Although no information about the existence of CSs was given to the subjects, suppression ratio results showed a discrimination learning curve-that is, subjects learned to suppress responding in anticipation of the US when Stimulus A was present but not during the presentations of Stimulus B. Experiment 2 explored the potential of this preparation by using two different instruction sets and assessing post-experimental judgements of CS A and CS B in addition to suppression ratios. The results of these experiments suggest that conditioned suppression can be reliably and conveniently used in the human laboratory, providing a bridge between experiments on animal conditioning and experiments on human judgements of causality.
Article
Full-text available
Similarities between Pavlovian conditioning in nonhumans and causal judgment by humans suggest that similar processes operate in these situations. Notably absent among the similarities is backward blocking (i.e., retrospective devaluation of a signal due to increased valuation of another signal that was present during training), which has been observed in causal judgment by humans but not in Pavlovian responding by animals. The authors used rats to determine if this difference arises from the target cue being biologically significant in the Pavlovian case but not in causal judgment. They used a sensory preconditioning procedure in Experiments 1 and 2, in which the target cue retained low biological significance during the treatment, and obtained backward blocking. The authors found in Experiment 3 that forward blocking also requires the target cue to be of low biological significance. Thus, low biological significance is a necessary condition for a stimulus to be vulnerable to blocking.
Chapter
This chapter describes the potential explanatory power of a specific response rule and its implications for models of acquisition. This response rule is called the “comparator hypothesis.” It was originally inspired by Rescorla's contingency theory. Rescorla noted that if the number and frequency of conditioned stimulus–unconditioned stimulus (CS–US) pairings are held constant, unsignaled presentations of the US during training attenuate conditioned responding. This observation complemented the long recognized fact that the delivery of nonreinforced presentations of the CS during training also attenuates conditioned responding. The symmetry of the two findings prompted Rescorla to propose that during training, subjects inferred both the probability of the US in the presence of the CS and the probability of the US in the absence of the CS and they then established a CS–US association based upon a comparison of these quantities. The comparator hypothesis is a qualitative response rule, which, in principle, can complement any model of acquisition.
Article
In the first experiment subjects were presented with a number of sets of trials on each of which they could perform a particular action and observe the occurrence of an outcome in the context of a video game. The contingency between the action and outcome was varied across the different sets of trials. When required to judge the effectiveness of the action in controlling the outcome during a set of trials, subjects assigned positive ratings for a positive contingency and negative ratings for a negative contingency. Furthermore, the magnitude of the ratings was related systematically to the strength of the actual contingency. With a fixed probability of an outcome given the action, judgements of positive contingencies decreased as the likelihood that the outcome would occur without the action was raised. Correspondingly, the absolute value of ratings of negative contingencies was increased both by an increment in the probability of the outcome in the absence of the action and by a decrement in the probability of the outcome following the action. A systematic bias was observed, however, in that positive judgements were given under a non-contingent relationship when the outcome frequency was relatively high. However, this bias could be reduced by giving extended exposure to the non-contingent schedule (Experiment 2). This pattern of contingency judgements can be explained if it is assumed that a process of selective attribution operates, whereby people are less likely to attribute an outcome to some potential target cause if another effective cause is present. Experiments 2 and 3 demonstrated the operation of this process by showing that initially establishing another agent as an effective cause of the outcome subsequently reduced or blocked the extent to which the subjects attributed the outcome to the action. Finally, we argue that the pattern and bias in contingency judgements based upon interactions with a causal process can be explained in terms of contemporary conditioning models of associative learning.
Article
These experiments examined the associative status of a 10-s CS (white noise) which, during Pavlovian conditioning, singly alternated with the US (footshock) in an explicitly unpaired fashion, with either a short (55 s) or with a long (420 s) intertrial interval. Results from conditioned punishment summation tests showed that following 8 sessions of conditioning (7 CSs and 7 USs in each session) the explicitly unpaired CS functioned as a conditioned excitor (Experiments 1-3), relative to the CS-only control, if the intertrial interval was short but not if that interval was long (Experiment 1). The excitatory property of the explicitly unpaired CS was still evident following a lengthy retention interval (28 days) during which rats remained in their home cage (Experiment 3). The explicitly unpaired CS functioned as a conditioned inhibitor if it had undergone extinction, after extinction of the contextual cues of the conditioning context (Experiment 2). Finally, the explicitly unpaired CS was also a conditioned inhibitor after only the contextual cues of the conditioning chamber were extinguished (Experiment 3). This latter finding was taken as evidence that under conditions of limited conditioning and when the CS and US trials are closely spaced, either excitatory CS-context and context-US associations or context-CS and CS-US associations, or all of these, were formed. These associations imbued the CS with enough excitation to not only obscure conditioned inhibition but to make the CS a net excitor.
Article
In animal research, blocking of instrumental responding is a well-known phenomenon, whereas no study has been reported that investigated blocking in human instrumental conditioning. Following the standard method used in nonhuman subjects, 48 students randomly assigned to one of three groups were exposed to a variable interval schedule (VI 10 s) in which reinforcement was delivered with a brief delay (500 ms). In the blocking condition, subjects experienced a tone stimulus during the delay (correlated group). In the two control conditions, subjects received either no tone (no-tone group) or the same number of tones as subjects of the correlated group, but the tones were independent of their behavior and reward (random group). As expected, instrumental responding was significantly lower in the correlated group than in either the no-tone or the random group. In a subsequent extinction phase, no difference in resistance was observed. A postexperimental interview revealed that subjects of the correlated group were more likely to detect the temporal nature of the reinforcement schedule than subjects of the other groups, but there was no relation to response rate. The data provide only little support for a notion of signal-induced enhanced learning, but do not challenge an interpretation in terms of associative competition between the response and the signal.
Article
A number of ways of taxonomizing human learning have ben proposed. We examine the evidence for one such proposal, namely, that there exist independent explicit and implicit learning systems. This combines two further distinctions, (1) between learning that takes place with versus without concurrent awareness, and (2) between learning that involves the encoding of instances (or fragments) versus the induction of abstract rules or hypotheses. Implicit learning is assumed to involve unconscious rule learning. We examine the evidence for implicit learning derived from subliminal learning, conditioning, artificial grammar learning, instrumental learning, and reaction times in sequence learning. We conclude that unconscious learning has not been satisfactorily established in any of these areas. The assumption that learning in some of theses tasks (e.g., artificial grammar learning) is predominantly based on rule abstraction is questionable. When subjects cannot report the ''implicitly learned'' rules that govern stimulus selection, this is often because their knowledge consists of instances or fragments of the training stimuli rather than rules. In contrast to the distinction between conscious and unconscious learning, the distinction between instance and rule learning is a sound and meaningful way of taxonomizing human learning. We discuss various computational models of these two forms of learning.
Article
Three experiments investigated whether a process akin to L. J. Kamin's (1969) blocking effect would occur with human contingency judgments in the context of a video game. 102 students were presented with sets of trials on each of which they could perform a particular action and observe whether the action produced a particular outcome in a situation in which there was an alternative potential cause of the outcome. Exp I showed that prior observation of the relationship between the alternative cause and the outcome did indeed block or reduce learning about the subsequent action-outcome relationship. However, exposure to the relationship between the alternative cause and the outcome after observing the association between the action and the outcome also reduced judgments of the action-outcome contingency (backward blocking), a finding at variance with conditioning theory. In Exp II, it was found that the degree of backward blocking depended on the predictive value of the alternative cause. Finally, Exp III showed that the backward blocking effect was not the result of greater forgetting about the action-outcome relationship in the experimental than in the control condition. Results cast doubt upon the applicability of contemporary theories of conditioning to human contingency judgment.
Article
Investigated in 3 experiments with undergraduates the effect of the L. J. Kamin (1969) "blocking" procedure on the conditioned electrodermal response in humans. Exp 1 found that Ss who underwent a blocking procedure exhibited a greater magnitude 1st anticipatory response (FAR) to the added element than Ss who received training on an appropriate unpaired control procedure. Exp 2 investigated the effect of the blocking procedure on the FAR using a within-S design. Exp 3 replicated the findings of Exp 2 using an auditory rather than visual stimulus as the added element. Taken together, results suggest that when the Kamin blocking procedure was used during electrodermal conditioning, the FAR exhibited characteristics opposite to those found with more traditional conditional responses (e.g., the response to the added element was not blocked but enhanced by this procedure). (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Article
This chapter presents the data which support the contention that stimulus selection is a potent effect, even in experimental situations that allow considerable control over the schedules of stimulation and reinforcement to which S is exposed. Yet, it is questioned whether or not such data demand an “attentional” interpretation. A theoretical alternative suggested “modified continuity theory” is discussed, and new data is presented for which this approach appears to offer a relatively unique account. Although at this time the theory must be regarded as especially tentative and incomplete, opportunity will be taken to suggest its potential usefulness in interpreting several phenomena that have been in search of theoretical integration. There are a number of common experimental procedures for evaluating the degree of focusing or stimulus selection. Perhaps the most obvious involves a comparison of the degree of learning exhibited to some stimulus when it is the only relevant cue available, as compared to a condition in which there are additional relevant cues. The degree to which the presence of additional relevant cues reduces the apparent amount learned is taken to indicate the degree of stimulus selection.
Article
When 2 cues occur together and reliably predict an outcome, Ss often judge the effect of the compound as reducible to the individual effects of the elements. This elemental processing in predictive learning is perhaps the single most important aspect of most theories of human inference. Surprisingly, selectional processing was not observed in either blocking or conditioned inhibition problems. Only when the learner had past experience with another problem encouraging an elemental strategy were the expected selectional processes observed. These proactive effects of prior learning were abolished if the earlier problem required a nonadditive solution. The results suggest that configural cues were guiding predictive inferences in the absence of elemental processes. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Article
A number of ways of taxonomizing human learning have been proposed. We examine the evidence for one such proposal, namely, that there exist independent explicit and implicit learning systems. This combines two further distinctions, (1) between learning that takes place with versus without concurrent awareness, and (2) between learning that involves the encoding of instances (or fragments) versus the induction of abstract rules or hypotheses. Implicit learning is assumed to involve unconscious rule learning. We examine the evidence for implicit learning derived from subliminal learning, conditioning, artificial grammar learning, instrumental learning, and reaction times in sequence learning. We conclude that unconscious learning has not been satisfactorily established in any of these areas. The assumption that learning in some of these tasks (e.g., artificial grammar learning) is predominantly based on rule abstraction is questionable. When subjects cannot report the “implicitly learned” rules that govern stimulus selection, this is often because their knowledge consists of instances or fragments of the training stimuli rather than rules. In contrast to the distinction between conscious and unconscious learning, the distinction between instance and rule learning is a sound and meaningful way of taxonomizing human learning. We discuss various computational models of these two forms of learning.
Article
Four eyelid conditioning experiments designed to be comparable to rabbit nictitating membrane (NMR) studies examined the blocking phenomenon in humans. All experiments utilized a within-subjects design, with Stage 1 of discrimination, Stage 2 of compound training, and a final test stage comparing responding to the blocked and non-blocked CSs. In two of the experiments (1 and 4) the comparison was made within subjects over all extinction trials. In Experiment 3 the test phase consisted of further reinforced training of the blocked and non-blocked CSs. These three experiments produced evidence of blocking when all extinction trials were entered into the analysis. Experiment 2, which involved a between-subjects comparison, failed to demonstrate the blocking effect. Wide variability both between and within subjects obscured the experimental effects. Post-experimental questionnaires designed to assess awareness of stimulus relations failed to identify a subjective blocking effect and showed no relationship to conditioned eyelid responding.
Article
Four experiments investigated the role of information value, or stimulus validity, in human electrodermal conditioning. Conditioned stimuli (CSs) were long, variable duration (10-50-sec) slides or sounds, the unconditioned stimulus (US) was shock, and the primary measures were change in tonic skin conductance level and self-report expectancy of shock. In Experiment 1 electrodermal responding to a target stimulus was marginally lower in a blocking group than in a superconditioning group. This difference failed to occur in Experiment 2, despite increased sensitivity of the electrodermal measure. Explicit instructions to pay attention to the relationship between each stimulus and shock improved learning, but did not lead to group differences (Experiment 3). In Experiment 4 expectancy ratings in a blocking group were lower than in an overshadowing group, but no electrodermal differences occurred. The results were interpreted in terms of non-additive learning processes such as occasion-setting, in addition to a general lack of transfer of learning about a stimulus from one context to another (element to compound or vice versa). It was suggested that sensitivity to stimulus validity might be observed if conditioning were embedded in a causally familiar task, as in contingency judgement research.
Article
Part 1 of this discussion summarizes several formal models of exicitatory classical conditioning. It is suggested that a central problem for all of them is the explanation of cases in which learning does not occur in spite of the fact that the CS is a signal for the reinforcer. A new model is proposed that deals with this problem by specifying that certain procedures cause a CS to lose effectiveness; in particular, it is argued that a CS will lose associability when its consequences are accurately predicted. In contrast to other current models, the effectiveness of the reinforcer remains constant throughout conditioning. Part 2 presents a reformulation of the nature of the learning produced by inhibitory-conditioning procedures and a discussion of the way in which such learning can be accommodated within the model outlined for excitatory learning. (47 ref)
Article
Associative blocking in human conditioning was investigated using electrodermal and self-reported US expectancy measures. Previous null results using a design reported by Lovibond, Siddle, and Bond (1988) suggested that a clearly demarcated phase structure and visual cues with semantic content may have distracted attention from the experimental contingencies. Therefore the current experiment intermixed pre-training and compound training trials and masked the transition to the test phase to remove or reduce phase boundaries. Simple coloured squares were used as CSs to reduce semantic content. A significant blocking effect was observed on both the expectancy measure and on the electrodermal measure. Both results were due to improved transfer of conditioning to the target CS in the overshadowing control group in comparison to previous experiments. The results were interpreted as providing evidence that previous null results were due to failure of transfer of learning across clearly distinct phases. There was no evidence of a dissociation between the electrodermal and self-report measures. Theoretical and procedural implications for human Pavlovian conditioning are discussed.
Article
The 1st part of this article evaluates the extent to which 2 elemental theories of conditioning, stimulus sampling theory and the Rescorla-Wagner (1972) theory, are able to account for the influence of similarity on discrimination learning. A number of findings are reviewed that are inconsistent with predictions derived from these theories, either in their present form or in various modified forms. The 2nd part of the article is concerned with developing an alternative, configural account for discrimination learning. In contrast to previous configural theories, the present version is set within the framework of a connectionist network.
Article
Waldmann and Holyoak (1992) presented evidence in support of the claim that cue selection does not emerge in "diagnostic" human learning tasks in which the cues are interpretable as effects and the outcomes as the causes of those effects. Waldmann and Holyoak argued that this evidence presents a major difficulty for associationist theories of learning and instead supports a "causal model" theory. We identify a number of flaws in Waldmann and Holyoak's experimental procedures and report three new experiments designed to test their claim. In Experiment 1, cue selection was observed regardless of causal order and regardless of whether the cues were abstractly or concretely specified. In Experiments 2 and 3, cue selection was again observed when subjects predicted causes from effects. We conclude that our results are consistent with simple associationist theories of learning but contradict Waldmann and Holyoak's causal model theory.
Article
Groups of rats were trained to bar-press for food reward, and a CER was superimposed upon the response rate by pairing a white noise with one of 5 intensities of shock. The acquisition of the CER, and its resistance to extinction, were monotonic functions of the US intensity, suggesting that "the parameters controlling the CER are identical with those controlling Pavlovian conditioning." From Psyc Abstracts 36:04:4EI28A.
Competició asociativa en aprendizaje humano. [Associative competition in human learning]. Unpublished doctoral dissertation
• N J Vila
Vila, N. J. (1996). Competició asociativa en aprendizaje humano. [Associative competition in human learning]. Unpublished doctoral dissertation. Seville, Spain: Universidad de Sevilla.
Competición asociativa en aprendizaje humano
• N J Vila
Vila, N. J. (1996). Competición asociativa en aprendizaje humano. [Associative competition in human learning]. Unpublished doctoral dissertation. Seville, Spain: Universidad de Sevilla.