Learning about reward identities and time.

We discuss three empirical findings that we think any theory attempting to integrate interval timing with associative learning concepts will need to address. These empirical phenomena all come from studies that combine peak timing procedures with reinforcer devaluation or conditional discrimination tasks commonly employed, respectively, in interval timing or associative learning research traditions. The three phenomena we discuss include: (1) the observation that disruptions in reward identity encoding have little to no impact on the encoding of reward time in the peak procedure (Delamateret al.

Habituation: It's not what you think it is.

In this review, we take a critical look at the methods used to document habituation and the theoretical assumptions that have been made about it. We point out problems associated with measuring habituation merely as a change over the course of repeated presentations of a stimulus. We argue that a common test procedure is essential to assess the relative magnitudes of habituation learning especially when different training procedures are examined.

Developments in associative theory: A tribute to the contributions of Robert A. Rescorla.

The field of associative learning theory was forever changed by the contributions of Robert A. Rescorla. He created an organizational structure that gave us a framework for thinking about the key questions surrounding learning theory: what are the conditions that produce learning?, what is the content of that learning?, and how is that learning expressed in performance? He gave us beautifully sophisticated experimental designs that tackled deep theoretical problems in experimentally clever and elegant ways.

Maintained goal-directed control with overtraining on ratio schedules.

It is thought that goal-directed control of actions weakens or becomes masked by habits over time. We tested the opposing hypothesis that goal-directed control becomes stronger over time, and that this growth is modulated by the overall action-outcome contiguity. Despite group differences in action-outcome contiguity early in training, rats trained under random and fixed ratio schedules showed equivalent goal-directed control of lever pressing that appeared to grow over time.

Comparative cognition-Conceptual and methodological advancements.

This special issue originally placed a Call for Papers that emphasized the importance of "Conceptual and Methodological" advances in the field of Comparative Cognition. Represented here is a collection of 14 papers that helps to display some of the diversity of ideas and approaches within this flourishing research area. The first paper in this issue, by Gazes and Lazareva (2021), discusses transitive inference learning from the perspectives of: identifying the problems of contextual variables in studying different species; whether associative processes can or cannot fully account for the behavior and, if not, what alternative representational mechanisms might be at work; and, finally, how ecological considerations may support comparative research by suggesting novel theoretical and empirical questions.

The retrosplenial cortex as a possible "sensory integration" area: A neural network modeling approach of the differential outcomes effect in negative patterning.

We explored the hypothesis that learning a Pavlovian negative patterning task would be facilitated when training with differential, as opposed to non-differential, reinforcing outcomes. Two groups of rats received pairings of one visual and one auditory stimulus with food reward when these stimuli were presented on separate training trials, but without reward when both stimuli were presented on simultaneous stimulus compound trials (V+, A+, AV-; similar to an XOR problem). For Group Differential, each stimulus was separately paired with distinctively tasting food rewards, whereas for Group Non-Differential each stimulus was randomly paired with both food reward types across different stimulus element trials.

Another look at the extinction of conditioned flavor preferences: Amount of training and tests for spontaneous recovery.

A conditioned flavor preference develops when hungry or thirsty rats experience a neutral flavor mixed in solution with a nutrient. In two sets of studies, we previously demonstrated that this learned preference is highly sensitive to flavor nonreinforcement (i.e.

Special issue on recent advances in perceptual learning.

This is an introduction to the special issue "Perceptual Learning." This collection of studies reflects some of the interesting new discoveries being made in the study of perceptual learning. Although much headway has been made toward understanding the basic phenomena, this collection of studies makes clear that there is much that remains to be understood.

Special issue to commemorate the intellectual contributions of Allan R. Wagner.

This is an introduction to the special issue "Wagner Tribute." Allan R. Wagner was the first editor in chief of this journal.

Inaugural editorial for Journal of Experimental Psychology: Animal Learning and Cognition.

The () has always been the most prestigious journal for researchers investigating basic mechanisms of animal learning, cognition, and behavior. It is with great humility and honor that I currently take on the role of editor. Since its inception our discipline has been deeply interested in exploring the psychological mechanisms involved in learning, cognition, and behavior in an effort to better understand how adaptive behavior and various cognitive capacities have evolved.

Chemogenetic inhibition in the dorsal striatum reveals regional specificity of direct and indirect pathway control of action sequencing.

Animals engage in intricate action sequences that are constructed during instrumental learning. There is broad consensus that the basal ganglia play a crucial role in the formation and fluid performance of action sequences. To investigate the role of the basal ganglia direct and indirect pathways in action sequencing, we virally expressed Cre-dependent Gi-DREADDs in either the dorsomedial (DMS) or dorsolateral (DLS) striatum during and/or after action sequence learning in D1 and D2 Cre rats.

Goal-directed control on interval schedules does not depend on the action-outcome correlation.

When an organism's action is based on an anticipation of its consequences, that action is said to be goal-directed. It has long been thought that goal-directed control is made possible by experiencing a strong correlation between response rates and reward rates (Dickinson, 1985). To test this idea, we designed a set of experiments to determine whether the response rate-reward rate correlation is a reliable predictor of goal-directed control on interval schedules.

Modeling Interval Timing by Recurrent Neural Nets.

The purpose of this study was to take a new approach in showing how the central nervous system might encode time at the supra-second level using recurrent neural nets (RNNs). This approach utilizes units with a delayed feedback, whose feedback weight determines the temporal properties of specific neurons in the network architecture. When these feedback neurons are coupled, they form a multilayered dynamical system that can be used to model temporal responses to steps of input in multidimensional systems.

Exploring the relationship between actions, habits, and automaticity in an action sequence task.

It is tempting to equate the automatization of an action sequence with the formation of a habit. However, the term "habit" specifically implies a failure to evaluate future consequences to guide behavior. To test if automatized sequences become habitual, we trained rats on an action sequence task for either 20 or 60 d and then conducted reward devaluation tests.

Outcome-specific Pavlovian-to-instrumental transfer (PIT) with alcohol cues and its extinction.

The acquired motivational impact of conditioned stimuli has been studied using the Pavlovian-to-instrumental transfer (PIT) task, where a cue paired with a reward is consistently shown to energize responses separately trained with that same reward ("specific" PIT). However, most alcohol studies have shown that alcohol-related cues elevate responses trained with either the same alcohol reward or with other non-alcoholic rewards ("general" PIT). The effects of extinction on this alcohol PIT effect have not been fully explored.

Sign-tracking is an expectancy-mediated behavior that relies on prediction error mechanisms.

When discrete localizable stimuli are used during appetitive Pavlovian conditioning, "sign-tracking" and "goal-tracking" responses emerge. Sign-tracking is observed when conditioned responding is directed toward the CS, whereas goal-tracking manifests as responding directed to the site of expected reward delivery. These behaviors seem to rely on distinct, though overlapping neural circuitries, and, possibly, distinct psychological processes as well, and are thought to be related to addiction vulnerability.

Learning what to expect and when to expect it involves dissociable neural systems.

Two experiments with Long-Evans rats examined the potential independence of learning about different features of food reward, namely, "what" reward is to be expected and "when" it will occur. This was examined by investigating the effects of selective reward devaluation upon responding in an instrumental peak timing task in Experiment 1 and by exploring the effects of pre-training lesions targeting the basolateral amygdala (BLA) upon the selective reward devaluation effect and interval timing in a Pavlovian peak timing task in Experiment 2. In both tasks, two stimuli, each 60 s long, signaled that qualitatively distinct rewards (different flavored food pellets) could occur after 20 s.

Associative mechanisms involved in specific Pavlovian-to-instrumental transfer in human learning tasks.

Four experiments compared the effect of forward and backward conditioning procedures on the ability of conditioned stimuli (CS) to elevate instrumental responding in a Pavlovian-to-instrumental transfer (PIT) task. Two responses were each trained with one distinct outcome (R->O, R->O), either concurrently (Experiment 1) or separately (Experiments 2, 3 and 4). Then, in Experiments 1 and 2, four CSs were either followed or preceded by one outcome (A->O, B->O O->C, O->D).

Extinction of specific stimulus-outcome (S-O) associations in Pavlovian learning with an extended CS procedure.

Three experiments with male and female rats were conducted to examine the effects of Pavlovian extinction training on Pavlovian-to-instrumental transfer (PIT) in a task in which the unconditioned stimulus (US) was presented at an early time point within an extended conditioned stimulus (CS). Two instrumental responses were trained with different reinforcing outcomes (R1-O1, R2-O2) and then, independently, 2 stimuli were trained with those outcomes (S1-O1, S2-O2). One group then underwent an extinction treatment (S1-, S2-) and a second was merely exposed to the experimental contexts without any stimulus events.

Superior ambiguous occasion setting with visual than temporal feature stimuli.

Three experiments with rats compared the relative ease with which different sets of visual or temporal cues could participate in Pavlovian learning. In Experiment 1, 1 group was trained to discriminate between visual cues (Light vs. Dark), whereas the other group learned to discriminate between temporal cues (early [10 s] vs.

Elemental, configural, and occasion setting mechanisms in biconditional and patterning discriminations.

Three experiments explored the utility of considering mechanisms of occasion setting for understanding patterning and biconditional discriminations - two more complex conditional discriminations in which the stimulus-outcome relations of occasion setting are embedded. In Experiment 1, rats were trained in an appetitive conditioning task with either a biconditional or a patterning discrimination using relatively brief CSs (10s) and differential outcomes as USs. In this study, rats learned the positive patterning task before they had learned negative patterning, and the biconditional task was the most difficult.

Temporal Averaging Across Stimuli Signaling the Same or Different Reinforcing Outcomes in the Peak Procedure.

The present study examined factors that affect temporal averaging in rats when discriminative stimuli are compounded following separate training indicating the availability of reward after different fixed intervals (FI) on a peak procedure. One group of rats, Group Differential, learned that a flashing light stimulus signaled that one type of food pellet reward could be earned for lever pressing after an FI 5 s interval and that a second type of food pellet reward could be earned after an FI 20 s interval in the presence of a tone stimulus. A second group of rats, Group Non-Differential, was similarly trained except that both types of rewards were scheduled across flash and tone trials.

Response-Outcome versus Outcome-Response Associations in Pavlovian-to-Instrumental Transfer: Effects of Instrumental Training Context.

One experiment with rats used Pavlovian-to-instrumental transfer (PIT) tests to explore potential competitive interactions between Pavlovian and instrumental processes during instrumental learning. Two instrumental response-outcome relations (e.g.

Dorsal hippocampus inactivation impairs spontaneous recovery of Pavlovian magazine approach responding in rats.

Destruction or inactivation of the dorsal hippocampus (DH) has been shown to eliminate the renewal of extinguished fear [1-4]. However, it has recently been reported that the contextual control of responding to extinguished appetitive stimuli is not disrupted when the DH is destroyed or inactivated prior to tests for renewal of Pavlovian conditioned magazine approach [5]. In the present study we extend the analysis of DH control of appetitive extinction learning to the spontaneous recovery of Pavlovian conditioned magazine approach responding.