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Cylinder Task
Author Information
Juan F. Duque
University of Nebraska-Lincoln
Lincoln, Nebraska, USA
Jeffrey R. Stevens
University of Nebraska-Lincoln
Lincoln, Nebraska, USA
Detour-reaching Task
Detour Task
A task that measures inhibitory control—the ability to inhibit inappropriate or
disadvantageous responses—using a reward placed within a transparent cylinder.
Subjects must inhibit moving directly toward visible reward and instead reach through
one of the cylinder openings at either end.
Duque, J.F. and Stevens, J.R. (2017). Cylinder task. In J. Vonk & T.K. Shackelford
(Eds.), Encyclopedia of animal cognition and behavior. New York: Springer.
A lioness spots a gazelle several meters away on a hill, but a line of tall savannah grass
separates her from her prey. She can proceed directly toward the gazelle, but crashing
through the grass would alert the prey to her presence. Alternatively, she could inhibit the
impulse to run straight toward the prey and detour around the tall grass to a better
location from which to launch her attack. Similarly, a subordinate chimpanzee may
inhibit its desire to mate or forage when in view of a dominant conspecific but seek those
opportunities when out-of-view behind a barrier. Animals face many problems that
require them to inhibit an action in lieu of a different, more goal-consistent behavioral
Inhibitory control is the ability to inhibit a powerful, almost automatic (prepotent)
response. Since prepotent responses often run counter to one’s goals, inhibitory control
is a core feature of executive functioning—the top-down cognitive control processes that
allow individuals to remain on track and achieve desired goals. In the case of the lioness,
she must inhibit the prepotent desire to move directly toward visible prey.
Researchers have used many tasks to measure inhibitory control (Table 1). Detour tasks
require subjects to detour around an obstacle or barrier to reach a desired location. The
cylinder task is a specific form of detour task in which subjects must retrieve a reward,
typically a food item, from within an opaque or transparent cylinder. This task, along
with other detour tasks, requires subjects to first inhibit the prepotent motor response to
move directly toward the visible reward. Instead, they must detour around the barrier
walls to obtain the reward through an available opening.
Other tasks require less motor action by focusing on choice or the withholding of
responses. In reverse contingency and A-not-B tasks, subjects attempt to obtain a reward
by choosing between a set of limited choices, with the prepotent choice not providing the
reward. Similarly, Go/No-Go tasks train subjects to respond to a frequently presented
stimulus, but this prepotent responding must be inhibited in certain situations. In delay of
gratification tasks, individuals must inhibit taking a reward that is available immediately
or after a short delay to obtain a more desirable reward available after a longer delay.
Table 1: Inhibitory Control Tasks
Detour Tasks
Cylinder Task
Other Shapes (cube/box)
Example reference
(Boogert, Anderson, Peters, Searcy, & Nowicki, 2011)
(Diamond, 1981)
(Köhler, 1925)
Choice Tasks
Reverse Contingency
Serial Reversal
Example reference
(Boysen & Berntson, 1995)
(Piaget, 1954)
(Mishkin & Pribram, 1955)
(Mcculloch & Pratt, 1934)
Delay of Gratification
Delay Maintenance
Example reference
(Grosch & Neuringer, 1981)
(Beran, Savage-Rumbaugh, Pate, & Rumbaugh, 1999)
Exchange (Ramseyer, Pele, Dufour, Chauvin, & Thierry, 2006)
Cylinder Task Procedure
The basic procedure of the cylinder task involves three phases.
Habituation Phase: Subjects habituate to the testing environments. This often
involves exposure to elements of the task that subjects have never, or rarely,
encountered, such as exposure to human experimenters, tracking hand
movements, and the presence of opaque cylinders.
Training Phase: An experimenter baits an opaque cylinder by placing a desired
reward in the center (Figure 1A). To correctly respond, subjects must detour
around the opaque cylinder and reach through one of the openings to obtain the
reward. Touching any part of the opaque wall first counts as an incorrect
response. To proceed to the next phase, subjects often must reach a certain
criterion level of success, typically, 80% correct responses in consecutive trials.
Figure 1. The cylinder apparatus. The Training Phase involves obtaining a reward
from within an opaque cylinder (A). After reaching criterion, the Testing Phase
involves the same procedure, except with a transparent cylinder (B). Subjects must
inhibit the prepotent response to move directly forward and instead detour through
one of the cylinder openings. Used with permission from MacLean et al. (2013).
Testing Phase: This phase is the same as the training phase, except with a
transparent cylinder (Figure 1B). Subjects must inhibit their prepotent response to
reach directly for the desired reward, hitting the transparent wall. Instead, they
must continue around to the ends of the cylinder to acquire the reward.
Researchers often measure performance as the proportion of correct responses or
the number of test trials required until the first correct response.
Cognitive Capacities for Inhibitory Control
Correctly avoiding the barrier and detouring through one of the openings requires several
cognitive capacities. In the training phase, the subject must maintain a memory of the
object after it is hidden inside the opaque cylinder (object permanence). In the testing
phase, the subject must understand the nature of physical barriers. In particular, they
must understand the solidity principle in which one solid object cannot pass through
another solid object. This is particularly relevant to transparent barriers where a subject’s
visual and tactile cues conflict. Lastly, the subject must combine knowledge and solve
the problem at hand to achieve the goal of obtaining the reward. Subjects can see the
reward through the transparent barrier, but they cannot directly access the food; therefore,
they must move around the barrier to reach the reward. To succeed in this task, subjects
must understand the physical state of the world (object permanence and solidity
principle) and exhibit an appropriate behavioral response (detour-reaching).
Behavioral Results
The simplicity of the cylinder task makes it easily amenable to comparative studies.
Indeed, researchers have tested several dozen species, ranging from pigeons to primates.
Overall, great apes, capuchin monkeys, rhesus macaques, canids, and corvids perform the
best with greater than 70% correct responses (Figure 2). Interestingly, some corvids
match or even surpass the performance of great apes.
Figure 2. Species performance in cylinder task. MacLean et al. (2014) and Kabadayi et
al. (2016) tested a combined 36 species of birds and mammals in the cylinder task. They
report each species’ mean percentage of correct trials during the Testing Phase.
Researchers have examined several evolutionary factors that may account for these
species differences in performance. Phylogenetic comparative methods indicate that
absolute brain volume predicts species differences in performance, along with relative
brain volume and dietary breadth. However, species differences in performance may also
result from how the animals engage in the task. Factors such as a subject’s motivation,
prior experience with opaque/transparent barriers, amount of habituation and training
trials prior to testing, and the degree of experimenter involvement during the task can
influence performance. Therefore, without further investigation into the various
contextual factors that impact performance, species differences should be interpreted with
The cylinder task is one of a suite of inhibitory control tasks. To assess whether
inhibitory control is a unitary construct, researchers have tested the same subjects in
multiple inhibitory control tasks. In general, within-individual performance across
inhibitory control tasks, e.g., A-not-B and the cylinder task, does not correlate. These
findings suggest that inhibitory control is multi-faceted and that various inhibitory control
tasks vary in the precise mechanisms activated.
Inhibitory control is a critical component of executive functioning, ensuring that
individuals maintain appropriate, goal-directed behavior. Detour tasks, such as the
cylinder task, test an individual’s ability to inhibit a prepotent desire to move directly
toward a visible reward. Species vary in their propensity to correctly solve the detour
task, and there may be evolutionary reasons for the species differences. Yet, we currently
do not have a clear understanding of the contextual factors influencing performance on
the detour task. Such data would be useful in elucidating the proximate mechanisms
subjects use during task performance and could clarify why results across multiple
inhibitory control tasks do not always correlate.
Canine cognition
Psitticine cognition
Behavioral variation
Species-specific behavior
Cattarhine cognition
Prosimian cognition
Proboscidea cognition
Visuo-spatial memory
Reversal learning
Rodentia cognition
Goal-directed behavior
Passerine cognition
Michael Beran
A not B problem
Associative learning
Brain size
Delayed gratification
Detour task
Transfer of learning
Behavioral flexibility
Go/no go procedure
Comparative cognition
Comparative psychology
Platyrrhine cognition
Primate cognition
Hominoidea cognition
Non-human primates
Experimental psychology
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34(2), 119–127.
Boogert, N. J., Anderson, R. C., Peters, S., Searcy, W. A., & Nowicki, S. (2011). Song
repertoire size in male song sparrows correlates with detour reaching, but not with
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Boysen, S. T., & Berntson, G. G. (1995). Responses to quantity: Perceptual versus
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discrimination by white rats. Journal of Comparative Psychology, 18(2), 271–
Mishkin, M., & Pribram, K. H. (1955). Analysis of the effects of frontal lesions in
monkeys: I. Variations of delayed alternations. Journal of Comparative and
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Basic Books.
Ramseyer, A., Pele, M., Dufour, V., Chauvin, C., & Thierry, B. (2006). Accepting loss:
the temporal limits of reciprocity in brown capuchin monkeys. Proceedings of the
Royal Society B: Biological Sciences, 273(1583), 179–184.
... For instance, the Cylinder tasks, one of the benchmark tests in large inter-species comparisons (MacLean et al., , 2017, is the subject of vivid debates (for review see Kabadayi, Bobrowicz & Osvath, 2018;Shaw & Schmelz, 2017). Factors such as prior experience (Duque & Stevens, 2017;Kabadayi, Bobrowicz & Osvath, 2018;van Horik et al., 2018bvan Horik et al., , 2019Vernouillet et al., 2018), can dramatically influence a subject's performance on this Detour task. Various authors advocate to circumvent this task impurity problem by using a battery of tasks putatively measuring the same ability (but differing in other task demands) to reveal a common underlying cognitive construct (Cauchoix et al., 2018;Friedman and Miyake 2017;Many Primates et al., 2019;Shaw & Schmelz, 2017;Völter et al., 2018). ...
... Many intricate factors can also influence inhibitory control performances (see Appendix 29 for a non-exhausting list of influencing factors). For instance, the motivation of the subjects can strongly influence their performances (Brucks, Marshall Pescini, Range 2018;Duque & Stevens 2017;Schubiger et al., 2020;Shaw & Schmelz 2017). Either in the wild or in captivity, if the experiment is voluntary, only the most motivated individuals from a group will be willing to interact with the experimental setup (Schubiger et al., 2020). ...
... It could be possible that their experience brought a bias in the data, explaining the better performances of the individuals from CPUS. In the literature, training and prior experience with behavioural experiment is one of the most described confounding factors of inhibitory control(Duque & Stevens, 2017;Kabadayi et al., 2018;van Horik et al., 2019; Vernouillet et al., 2018, see Appendix 29). Experienced individuals can have an advantage in physical understanding of the task (i.e., object permanence, spatial relationship, transparency;Duque & Stevens 2017;Kabadayi et al., , 2018. ...
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Living in a complex social environment requires primates to manage their emotions and inhibit impulsive behaviours. The cognitive processes that underpin these behaviours, crucial in many aspects of everyday life, are defined as inhibitory control. In animal studies, the various paradigms designed to measure inhibitory control often suffer from a lack of systematic validation. Moreover, striking individual variations in inhibitory control performances are often largely ignored and their causes rarely considered. Finally, little is known about the selective forces that shape the evolution of inhibitory control. It has been suggested that one route by which this ability can be enhanced is through selection on social tolerance. Hence the aim of this project was threefold: 1-to develop a battery of inhibitory control tasks in non-human primates 2-to use this task battery to systematically investigate individual variability and its most common causes 3-on a broader evolutionary scale, to compare the inhibitory control skills in three species which differ in social tolerance style. For that purpose, we tested 66 macaques (28 Macaca mulatta, 19 M. fascicularis and 18 M. tonkeana) in a battery of touchscreen tasks assessing three main components of inhibitory control: inhibition of a distraction (using a Distraction task), inhibition of an impulsive action (using a Go/No-go task) and inhibition of a cognitive set (using a Reversal learning task). We found that all tasks were reliable and effective at measuring the inhibition of an impulsive and automatic response. We then demonstrated individual variations, sex and age differences in inhibitory control performances. Finally we demonstrated that the least tolerant species were poorer at controlling their emotions and impulsions compared to other species. Overall, this project will help to get more insight into the multifaceted structure and the evolution of inhibitory control in primates.
... Controlling impulsive behavior is an essential contributor to culturally suitable conduct in humans, enabling successful function of our societies (Steelandt, Thierry, Broihanne, & Dufour, 2012). Inhibitory control is the ability to inhibit a strong, prepotent response that is likely to be tempting to execute but counterproductive to achieving a future goal (Duque & Stevens, 2017;Kabadayi, Taylor, von Bayern, & Osvath, 2016). It is an integral part of executive functioning, along with working memory and cognitive flexibility (Diamond, 2013). ...
... For example, it is seen as an important cognitive prerequisite of cooperation, when individuals help a conspecific now in order to receive a favor in the future (Stevens & Hauser, 2004). Also, when in the presence of a stronger or more dominant competitor, an animal may inhibit their behavior by avoiding an immediate, direct approach to food or a potential mate (Duque & Stevens, 2017). For instance, one female chimpanzee (Pan troglodytes) learned to inhibit going to a hidden food that only she knew about when a dominant male could take that food (Menzel, 1974). ...
... Social paradigms indicate that in humans, the presence and behavior of others can influence decision-making. Flexibility in self-control is likely to be important in a social context in nonhuman animals too, for instance, refraining from approaching food or a potential mate while in the presence of a competitor (Bugnyar, 2011;Duque & Stevens, 2017). Despite this, there are only a few tasks that require interaction with a conspecific, which are primarily the exchange paradigms in primates (Table S1). ...
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Self‐control is critical for both humans and nonhuman animals because it underlies complex cognitive abilities, such as decision‐making and future planning, enabling goal‐directed behavior. For instance, it is positively associated with social competence and life success measures in humans. We present the first review of delay of gratification as a measure of self‐control in nonhuman primates, corvids (crow family) and psittacines (parrot order): disparate groups that show comparable advanced cognitive abilities and similar socio‐ecological factors. We compare delay of gratification performance and identify key issues and outstanding areas for future research, including finding the best measures and drivers of delayed gratification. Our review therefore contributes to our understanding of both delayed gratification as a measure of self‐control and of complex cognition in animals. This article is categorized under: • Cognitive Biology > Evolutionary Roots of Cognition • Psychology > Comparative Psychology Abstract Examples of delayed gratification tasks. (a) Exchange task with a corvid: subject can choose to swap a token (e.g., bottle top) for a reward after a delay; (b) Intertemporal choice: monkey can select the immediately available reward or wait for the delayed reward from a rotating tray.
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Inhibitory control, the ability to override an inappropriate prepotent response, is crucial in many aspects of everyday life. However, the various paradigms designed to measure inhibitory control often suffer from a lack of systematic validation and have yielded mixed results. Thus the nature of this ability remains unclear, is it a general construct or a family of distinct sub-components? Therefore, the aim of this study was first to demonstrate the content validity and the temporal repeatability of a battery of inhibitory control tasks. Then we wanted to assess the contextual consistency of performances between these tasks to better understand the structure of inhibitory control. We tested 21 rhesus macaques ( Macaca mulatta , 12 males, nine females) in a battery of touchscreen tasks assessing three main components of inhibitory control: inhibition of a distraction (using a Distraction task), inhibition of an impulsive action (using a Go/No-go task) and inhibition of a cognitive set (using a Reversal learning task). All tasks were reliable and effective at measuring the inhibition of a prepotent response. However, while there was consistency of performance between the inhibition of a distraction and the inhibition of an action, representing a response-driven basic form of inhibition, this was not found for the inhibition of a cognitive set. We argue that the inhibition of a cognitive set is a more cognitively demanding form of inhibition. This study gives a new insight in the multifaceted structure of inhibitory control and highlights the importance of a systematic validation of cognitive tasks in animal cognition.
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Overriding motor impulses instigated by salient perceptual stimuli represent a fundamental inhibitory skill. Such motor self-regulation facilitates more rational behaviour, as it brings economy into the bodily interaction with the physical and social world. It also underlies certain complex cognitive processes including decision making. Recently, MacLean et al.(MacLean et al. 2014 Proc. Natl Acad. Sci. USA 111, 2140–2148.(doi:10.1073/pnas.1323533111))conducted a large-scale study involving 36 species, comparing motor self-regulation across taxa. They concluded that absolute brain size predicts level of performance. The great apes were most successful. Only a few of the species tested were birds. Given birds’ small brain size—in absolute terms—yet flexible behaviour, their motor self-regulation calls for closer study. Corvids exhibit some of the largest relative avian brain sizes—although small in absolute measure—as well as the most flexible cognition in the animal kingdom. We therefore tested ravens, New Caledonian crows and jackdaws in the so-called cylinder task. We found performance indistinguishable from that of great apes despite the much smaller brains. We found both absolute and relative brain volume to be a reliable predictor of performance within Aves. The complex cognition of corvids is often likened to that of great apes; our results show further that they share similar fundamental cognitive mechanisms.
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Significance Although scientists have identified surprising cognitive flexibility in animals and potentially unique features of human psychology, we know less about the selective forces that favor cognitive evolution, or the proximate biological mechanisms underlying this process. We tested 36 species in two problem-solving tasks measuring self-control and evaluated the leading hypotheses regarding how and why cognition evolves. Across species, differences in absolute (not relative) brain volume best predicted performance on these tasks. Within primates, dietary breadth also predicted cognitive performance, whereas social group size did not. These results suggest that increases in absolute brain size provided the biological foundation for evolutionary increases in self-control, and implicate species differences in feeding ecology as a potential selective pressure favoring these skills.
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The social intelligence hypothesis suggests that living in large social networks was the primary selective pressure for the evolution of complex cognition in primates. This hypothesis is supported by comparative studies demonstrating a positive relationship between social group size and relative brain size across primates. However, the relationship between brain size and cognition remains equivocal. Moreover, there have been no experimental studies directly testing the association between group size and cognition across primates. We tested the social intelligence hypothesis by comparing 6 primate species (total N = 96) characterized by different group sizes on two cognitive tasks. Here, we show that a species' typical social group size predicts performance on cognitive measures of social cognition, but not a nonsocial measure of inhibitory control. We also show that a species' mean brain size (in absolute or relative terms) does not predict performance on either task in these species. These data provide evidence for a relationship between group size and social cognition in primates, and reveal the potential for cognitive evolution without concomitant changes in brain size. Furthermore our results underscore the need for more empirical studies of animal cognition, which have the power to reveal species differences in cognition not detectable by proxy variables, such as brain size.
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Two chimpanzees were trained to select among 2 different amounts of candy (1-6 items). The task was designed so that selection of either array by the active (selector) chimpanzee resulted in that array being given to the passive (observer) animal, with the remaining (nonselected) array going to the selector. Neither animal was able to select consistently the smaller array, which would reap the larger reward. Rather, both animals preferentially selected the larger array, thereby receiving the smaller number of reinforcers. When Arabic numerals were substituted for the food arrays, however, the selector animal evidenced more optimal performance, immediately selecting the smaller numeral and thus receiving the larger reward. These findings suggest that a basic predisposition to respond to the perceptual-motivational features of incentive stimuli can interfere with task performance and that this interference can be overridden when abstract symbols serve as choice stimuli.
Developmental and child psychology remains a vital area in modern psychology. This comprehensive set covers a broad spectrum of developmenal issues, from the psychology of the infant, the family, abilities and disabilities, children's art, imagination, play, speech, mental development, perception, intelligence, mental health and education. In looking at areas which continue to be very important today, these volumes provide a fascinating look at how approaches and attitudes to children have changed over the years. The set includes nine volumes by key development psychologist Jean Piaget, as well as titles by Charlotte Buhler and Susan Isaacs.
Monkeys with lesions of the frontal granular cortex showed severe impairment of learning ability on problems requiring right-left alternation, up-down alternation or "go, no-go" respond or not respond type of response to a single stimulus object. Correct responses in the latter problem rose to above-chance levels, but only after a longer series of trials than were necessary for control animals. The experimenters suggest that some factor in addition to delay is needed to explain the impairment on delayed-response tasks shown by animals with frontal lesions. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Different kinds and amounts of preliminary training on a weight-discrimination problem involving the pulling-in technique were used with a view to ascertaining the influence of such training on the mastery of a standard problem. This problem was to pull in the heavier of the stimuli. Five groups were given, respectively, the following preliminary training, making subsequently the number of errors on the standard problem indicated in parentheses: 28 trials with food in lighter tray (64.3); drawing in lighter tray for food until manifesting evidence of discrimination (94.6); 348 trials with food in lighter tray (115.8); 84 trials with both trays equally weighted (49.2). A control group which learned to draw in the heavier tray without preliminary training of the kind indicated above required 52 trials for mastery. "The excess errors may be considered proportional to the preceding training provided that the errorless trials are considered as producing some small effect. This demonstration of the cumulative effect of training which is roughly proportional to the number of errors made seems to establish the validity of the assumption that, under the conditions of the present study, at least, errors may be considered as comparable units of measurement, and that a summation of errors may be taken to represent ability on a specific test." (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Kohler's work first appeared in 1917, under the title Intelligenzprufen an Anthropoiden. The English translation of the second revised edition, under the title given above, was first published in 1924 and is adapted for this chapter. Two sets of interests lead us to test the intelligence of the higher apes. We are aware that it is a question of beings which in many ways are nearer to man than to the other ape species; in particular it has been shown that the chemistry of their bodies, in so far as it may be perceived in the quality of the blood, and the structure of their most highly-developed organ, the brain, are more closely related to the chemistry of the human body and human brain-structure than to the chemical nature of the lower apes and their brain development. These beings show so many human traits in their "everyday" behaviour that the question naturally arises whether they do not behave with intelligence and insight under conditions which require such behaviour. This question expresses the first, one may say, naive, interest in the intellectual capacity of animals. We wished to ascertain the degree of relationship between anthropoid apes and man in a field which seems to us particularly important, but on which we have as yet little information. The second aim is theoretical. Even assuming that the anthropoid ape behaves intelligently in the sense in which the word is applied to man, there is yet from the very start no doubt that he remains in this respect far behind man, becoming perplexed and making mistakes in relatively simple situations; but it is precisely for this reason that we may, under the simplest conditions, gain knowledge of the nature of intelligent acts. In the field of the experiments carried out here the insight of the chimpanzee shows itself to be principally determined by his optical apprehension of the situation; at times he even starts solving problems from a too visual point of view, and in many cases in which the chimpanzee stops acting with insight, it may have been simply that the structure of the situation was too much for his visual grasp (relative "weakness of form perception"). It is therefore difficult to give a satisfactory explanation of all his performances, so long as no detailed theory of form (Gestalt) has been laid as a foundation. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Song learning is a cognitive task in which juvenile birds acquire, store and use information about adult song to shape their own song production. Comparative studies show that across bird species, performance on different cognitive tasks is usually positively correlated. If the same holds true within species, then the complexity of a male's learned song ought to be correlated with other cognitive abilities. To test this hypothesis, we measured correlations between song repertoire size and cognitive performance in wild song sparrows, Melospiza melodia. Females prefer males with larger song repertoires in this species, and song repertoire size correlates with various fitness measures. We recorded males' song repertoires in the field and tested these males in captivity on motor, colour association and reversal learning tasks, as well as on a detour-reaching task that measures inhibitory control. We found that individuals' performance on the colour association task correlated positively with their performance on the reversal task, but performance did not correlate across the other learning tasks. Males with larger song repertoires were faster to solve the detour-reaching task, but performed worse on the reversal task than males with smaller song repertoires. Although our results suggest that song repertoire size does correlate with one measure of cognitive performance, more detailed song analyses and further cognitive tests are required to answer the questions raised by our findings.
Delay of gratification in 3 chimpanzees (Pan troglodytes) was examined by using a paradigm based on research with children. The chimpanzees either pressed a door-bell button during a trial and received one reward (the immediate reward) or did not press the doorbell and received another reward (the delayed reward). Two chimpanzees were language-trained, and a 3rd was non-language-trained. Foods (one more-preferred and one less-preferred), photographs of those foods, or lexigrams representing those foods were presented to the chimpanzees. All 3 chimpanzees delayed gratification when foods were physically present. One language-trained chimpanzee also delayed gratification with lexigrams present, and the 2nd language-trained chimpanzee delayed gratification in all three conditions. Language competence and early rearing are proposed as explanations for the different performances of these chimpanzees.