Aaron P Blaisdell

University of California, Los Angeles | UCLA · Department of Psychology

Humans and other animals are capable of reasoning. However, there are overwhelming examples of errors or anomalies in reasoning. In two experiments, we studied if rats, like humans, estimate the conjunction of two events as more likely than each event independently, a phenomenon that has been called conjunction fallacy. In both experiments, rats le...

Being able to correctly identify a target when presented with multiple possible alternatives, or increasing uncertainty, is highly beneficial in a wide variety of situations. This has been intensely investigated with human participants and results consistently demonstrated that participant reaction time (RT) increases linearly with the number of re...

Pigeons are commonly utilized in psychological research, and their cognitive abilities have been thoroughly investigated. Yet very little is known about how these abilities change with age. In contrast, age-related changes in humans, nonhuman primates, and rodents are well documented. Mammalian research consistently shows that older subjects show d...

Behavioral flexibility, adapting behavior to changing situations, is hypothesized to be related to adapting to new environments and geographic range expansions. However, flexibility is rarely directly tested in a way that allows insight into how flexibility works. Research on great-tailed grackles, a bird species that has rapidly expanded their ran...

Research into animal cognitive abilities is increasing quickly and often uses methods where behavioral performance on a task is assumed to represent variation in the underlying cognitive trait. However, because these methods rely on behavioral responses as a proxy for cognitive ability, it is important to validate that the task structure does, in f...

Psychologists use experiments to understand causal relationships. The effects that we observe are typically shown in subsets of people using specific stimuli, yet we assume these specific effects can generalize to many different populations and circumstances than specifically tested. Here, we provide a clear demonstration of how the set of stimuli...

For over two decades, phasic activity in midbrain dopamine neurons was considered synonymous with the prediction error in temporal-difference reinforcement learning.[1], [2], [3], [4] Central to this proposal is the notion that reward-predictive stimuli become endowed with the scalar value of predicted rewards. When these cues are subsequently enco...

Evolution of Learning and Memory Mechanisms is an exploration of laboratory and field research on the many ways that evolution has influenced learning and memory processes, such as associative learning, social learning, and spatial, working, and episodic memory systems. This volume features research by both outstanding early-career scientists as we...

We studied object–location binding in pigeons using a sequence learning procedure. A sequence of four objects was presented, one at a time at one of four locations on a touchscreen. A single peck at the object ended the trial, and food reinforcement was delivered intermittently. In Experiment 1, a between-subjects design was used to present objects...

In our daily life, we visually perceive an external space and effortlessly navigate through it. Although visual stimulation reaches the 2D retinas in the egocentric frame, our brains appear to reconstruct and maintain external allocentric 3D space regardless of constantly moving eyes, head, and body. How can the 2D egocentric retinotopy be converte...

Human vision has a remarkable ability to recognize complex 3D objects such as faces that appear at any size and 3D orientations at any 3D location. If we initially memorize a face only with a normalized size upfront at the object center, the direct comparison between the one-sized memory and an incoming new image would demand tremendous mental fram...

Visual perception plays a critical role in navigating space and extracting useful semantic information crucial to survival. To identify distant landmarks, we constantly shift gaze vectors through saccades, while still maintaining the visual perception of stable allocentric space. How can we sustain stable allocentric space so effortlessly? To solve...

Human vision has a remarkable ability to recognize complex 3D objects such as faces that appear with any size and 3D orientations at any 3D location. If we initially memorize a face only with a normalized size and viewed from directly head on, the direct comparison between the one-sized memory and a new incoming image would demand tremendous mental...

Visual perception plays a critical role in navigating 3D space and extracting semantic information crucial to survival. Even though visual stimulation on the retina is fundamentally 2D, we seem to perceive the world around us in vivid 3D effortlessly. This reconstructed 3D space is allocentric and faithfully represents the external 3D world. How ca...

Behavioral flexibility should, theoretically, be positively related to behavioral inhibition because one should need to inhibit a previously learned behavior to change their behavior when the task changes (flexibility). However, several investigations show no or mixed support of this hypothesis, which challenges the assumption that inhibition is in...

For over two decades, midbrain dopamine was considered synonymous with the prediction error in temporal-difference reinforcement learning. Central to this proposal is the notion that reward-predictive stimuli become endowed with the scalar value of predicted rewards. When these cues are subsequently encountered, their predictive value is compared t...

Behavioral flexibility, the ability to adapt behavior to new circumstances, is thought to play an important role in a species’ ability to successfully adapt to new environments and expand its geographic range. However, flexibility is rarely directly tested in species in a way that would allow us to determine how flexibility works to predict a speci...

Behavioral flexibility, the ability to change behavior when circumstances change based on learning from previous experience, is thought to play an important role in a species ability to successfully adapt to new environments and expand its geographic range. It is alternatively or additionally possible that causal cognition, the ability to understan...

The acquisition of instrumental responding can be supported by primary reinforcers or by conditional (also known as secondary) reinforcers that themselves have an association to a primary reinforcer. While primary reinforcement has been heavily studied for the past century, the associative basis of conditioned reinforcement has received comparative...

Spatial learning and memory, the processes through which a wide range of living organisms encode, compute, and retrieve information from their environment to perform goal-directed navigation, has been systematically investigated since the early twentieth century to unravel behavioral and neural mechanisms of learning and memory. Early theories abou...

Higher-order conditioning involves learning causal links between multiple events, which then allows one to make novel inferences. For example, observing a correlation between two events (e.g., a neighbor wearing a particular sports jersey), later helps one make new predictions based on this knowledge (e.g., the neighbor’s wife’s favorite sports tea...

Given a choice, pigeons prefer an initial-link stimulus that is followed by reliable signals that food will be delivered (S+) or not (S-) after a delay, over an alternative initial-link stimulus that is followed by unreliable signals of food, even when the former yields a lower overall probability of food. This suboptimal preference has been attrib...

The study of memory is commonly associated with neuroscience, aging, education, and eyewitness testimony. Here we discuss how eating behavior is also heavily intertwined-and yet considerably understudied in its relation to memory processes. Both are influenced by similar neuroendocrine signals (e.g., leptin and ghrelin) and are dependent on hippoca...

Raven’s progressive matrices (RPM) is a nonverbal intelligence test that examines abstract reasoning by asking subjects to correctly complete a stimulus matrix where transformations between stimuli in the matrix follow one or more relational rules. While this test has been used since 1936, and has been modified to accommodate a variety of humans, t...

How well do we remember eating food? Some nutritional scientists have decried memory of eating as being highly unreliable (i.e. low in accuracy), but it is unclear if memory of eating is particularly worse than memory of other behaviors. In fact, evolutionary reasoning suggests the mammalian memory system might be biased towards enhanced memory of...

Operant chambers are small enclosures used to test animal behavior and cognition. While traditionally reliant on simple technologies for presenting stimuli (e.g., lights and sounds) and recording responses made to basic manipulanda (e.g., levers and buttons), an increasing number of researchers are beginning to use Touchscreen-equipped Operant Cham...

Behavioral flexibility should theoretically be positively related to behavioral inhibition (hereafter referred to as inhibition) because one should need to inhibit a previously learned behavior to change their behavior when the task changes (the flexibility component;). However, several investigations show no or mixed support of this hypothesis, wh...

The study of intelligence in humans has been ongoing for over 100 years, including the underlying structure, predictive validity, related cognitive measures, and source of differences. One of the key findings in intelligence research is the uniform positive correlations among cognitive tasks. This has been replicated with every cognitive test batte...

Behavioral flexibility, the ability to change behavior when circumstances change based on learning from previous experience, is thought to play an important role in a species’ ability to successfully adapt to new environments and expand its geographic range. However, it is possible that causal cognition, the ability to understand relationships beyo...

Operant chambers are small enclosures used to test animal behavior and cognition. While traditionally reliant on simple technologies for presenting stimuli (e.g., lights and sounds) and recording responses made to basic manipulanda (e.g., levers and buttons), an increasing number of researchers are beginning to use Touchscreen-equipped Operant Cham...

The cognitive map has been taken as the standard model for how agents infer the most efficient route to a goal location. Alternatively, path integration – maintaining a homing vector during navigation – constitutes a primitive and presumably less‐flexible strategy than cognitive mapping because path integration relies primarily on vestibular stimul...

The study of memory is commonly associated with neuroscience, aging, education, and eyewitness testimony. Here we discuss how eating behavior is also heavily intertwined—and yet considerably understudied in its relation to memory processes. Both are influenced by similar neuroendocrine signals (e.g., leptin and ghrelin) and are dependent on hippoca...

It is unclear if, and to what extent, the human memory system is biased towards food and food relevant stimuli. Drawing upon existing demonstrations of attentional biases to high calorie food images, and findings that evolutionarily relevant stimuli are preferentially remembered, we hypothesized that images of high calorie foods would be better rem...

Beginning with Pavlov (1927), there has been great interest in how associative learning processes affect eating behavior. For instance, flavors can become preferred when paired with calories or, conversely, become aversive when paired with illness. This relationship between flavors and caloric or toxic outcomes has been investigated by a number of...

We studied object-location binding in pigeons using a sequence learning procedure. A sequence of four objects was presented, one at a time at one of four locations on a touchscreen. A single peck at the object ended the trial, and food reinforcement was delivered intermittently. In Experiment 1, a between-subjects design was used to present objects...

Thorndike’s Law of Effect provides a framework for understanding the selection of behaviors given specific environmental reward contingencies. Though a highly influential model, especially given its resurgence in popularity to understand habitual behaviors, it fails to predict several well-documented behavioral phenomena and incorrectly views extin...

Are all memories created equal, or are we biased to remember information most relevant to our evolutionary fitness? This question is underexplored in dominant models of memory that often treat all incoming information with equal potential to be remembered. We hypothesized that memory is systematically biased towards remembering fitness-relevant beh...

To examine the cognitive and physical changes associated with consuming an energy drink concurrent to video gaming, we examined a convenience sample of nine elite League of Legends (LoL) e-sport players (21 ± 2 y, BMI 25.6 ± 3.4 kg/m 2) consuming an energy drink (Reload TM) or placebo (Placebo) in a randomized, double-blind, placebo-controlled cros...

When we open our eyes, we see a world filled with objects and events. Yet, due to occlusion of some objects by others, we only have partial perceptual access to the events that transpire around us. I discuss the body of research on mental imagery in animals. I first cover prior studies of mental rotation in pigeons and imagery using working memory...

Deeply rooted within the history of experimental psychology is the search for general laws of learning that hold across tasks and species. Central to this enterprise has been the notion of equipotentiality; that any two events have the same likelihood of being associated with one another as any other pair of events. Much work, generally summarized...

Encyclopedia entry on Animal Rationality published in the Encyclopedia on Animal Cognition and Behavior

Biographical entry on Ralph R. Miller published in the Encyclopedia on Animal Cognition and Behavior.

Tolman bucked the behaviorist ideology early on when he introduced a cognitive framework for instrumental behavior. He spoke of outcome expectancies and the goal-directed nature of instrumental and operant learning. This framework is supported by recent behavioral and neurobiological findings, which provide evidence for the dissociation between hab...

Age-related decrements in cognitive ability have been proposed to stem from deteriorating function of the hippocampus. Many birds are long lived, especially for their relatively small body mass and elevated metabolism, making them a unique model of resilience to aging. Nevertheless, little is known about avian age-related changes in cognition and h...

We've shown that pigeons can integrate separately acquired spatial maps into a cognitive map. Integration requires an element shared between maps. In two experiments using a spatial-search task in pigeons, we test spatial combination rules when no shared element was present during training. In all three experiments, pigeons first learned individual...

Prior work in our lab has shown that an expanding image on a computer screen elicits a hiding response in the Caribbean terrestrial hermit crab (Coenobita clypeatus ). We conducted two experiments to identify what properties of the expanding stimulus contribute to its effectiveness as a visual threat. First we found that an expanding geometric star...

Raw data for Experiment 1

Raw data for Experiment 2

A series of experiments illustrated the effectiveness and flexibility of a newly developed Automated Remote Environmental Navigation Apparatus (ARENA) as an alternative to traditional operant and open-field procedures. This system improves the concept developed by Badelt and Blaisdell (Behavior Research Methods, 40, 613-621, 2008; see also Leising,...

Diets consisting of refined foods (REF) are associated with poor physical (e.g., obesity and diabetes) and mental (e.g., depression) health and impaired cognition. Few animal studies have explored the causal links between diet processing and health. Instead, most studies focus on the role of macronutrients, especially carbohydrate and fat concurren...

Extensive research has documented evidence for rule learning in sequential behavior tasks in both rats and humans. We adapted the 2-choice serial multiple choice (SMC) task developed for use with rats (Fountain & Rowan, 1995a) to study sequence behavior in pigeons. Pigeons were presented with 8 disks arranged in a circular array on a touchscreen, a...

Mental imagery involves the perceptual-like experience of an event that is not physically present, or detected by the senses. Fast and Blaisdell (2011) reported that rats use the representation of an associatively retrieved event to guide behavior in ambiguous situations. Rats were reinforced for lever-pressing during 1 of 2 lights but not both lig...

We investigated theoretical accounts of spatial overshadowing using a landmark-based spatialsearch task in a touchscreen preparation with pigeons. Pigeons first learned to find a hidden target on a screen using a compound of two visual cues as landmarks. Landmark A was proximal to the target while landmark X was distal to the target. Experiment 1 r...

A predominant trend throughout the evolution of animals has been an increase in neural complexity. Comparative cognition research investigates cognition in diverse species to better understand the evolution of cognition. I present research from my own lab involving rats, pigeons, and hermit crabs, that illustrates some basic cognitive processes fou...

Identifying statistical patterns between environmental stimuli enables organisms to respond adaptively when cues are later observed. However, stimuli are often obscured from detection, necessitating behavior under conditions of ambiguity. Considerable evidence indicates decisions under ambiguity rely on inference processes that draw on past experie...

We investigated extinction and spontaneous recovery of spatial associations using a landmark-based appetitive search task in a touchscreen preparation with pigeons. Four visual landmarks (A, B, C, and D) were separately established as signals of a hidden reinforced target among an 8 x 7 array of potential target locations. The target was located ab...

Children love to play. Why do they find such a frivolous activity so pleasurable and desirable? Perhaps it is not frivolous, but instead is an adaptation designed to guide proper cognitive development in human children. To understand why, I marshal evidence from different fields to build a case for play as a central behavioral mechanism of human br...

Many studies investigating cue competition have focused on the blocking effect. We investigated the blocking effect with pigeons using a landmark-based spatial search task in both a touchscreen preparation (Exp. 1a) and an automated remote environmental navigation apparatus (Exp. 1b). In Phase 1, two landmarks (LMs: A and Z) appeared on separate tr...

The human body—an amazing biological system that scales up fractally from its cellular building blocks—exhibits an incredible ability to self heal. Why then, are chronic diseases and degeneration on the rise in the population? Why are we sicker, more obese, and more depressed and stressed than ever before in human history? Why can’t we heal? The an...

Variation in behaviour is an essential ingredient and necessary precondition for creativity. This chapter explores the role of associative learning processes in the generation of behavioural variability. Behavioural variability can be explicitly selected through reinforcement. Importantly, operant variability appears to reflect instrumental control...

We examined how spatial language affected search behavior in a landmark spatial search task. In Experiment 1, two- to six-year-old children were trained to find a toy in the center of a square array of four identical landmarks. Children heard one of three spatial language cues once during the initial training trial (“here,” “in the middle,” “next t...

There is much interest in studying animal personalities but considerable debate as to how to define and evaluate them. We assessed the utility of one proposed framework while studying personality in terrestrial hermit crabs (Coenobita clypeatus). We recorded the latency of individuals to emerge from their shells over multiple trials in four unique...

The goal of three experiments was to study whether rats are aware of the difference between absence of events and lack of evidence. We used a Pavlovian extinction paradigm in which lights consistently signaling sucrose were suddenly paired with the absence of sucrose. The crucial manipulation involved the absent outcomes in the extinction phase. Wh...

Although food reward plays a large role in learning and behavioral experiments, there have been few studies examining the most motivating food reward for pigeons. Brown (1969) found that pigeons had a tendency to prefer peas, while Killeen et al. (1993) found pigeons to prefer peas and popcorn in Experiment 1A. We looked to further explore these op...