In two experiments hungry rats received extensive training to lever press for food outcomes before one outcome was devalued by aversion conditioning and responding tested in extinction. If the were trained on a concurrent schedule which responses yielded different outcomes, performance during extinction test reduced devaluation of associated outcome. By contrast, if single response concurrently with noncontingent presentations other outcome, insensitive contingent This finding demonstrates...

In three experiments, the nature of interaction between multiple memory systems in rats solving a variation spatial task water maze was investigated. Throughout training were able to find submerged platform at fixed distance and direction from an intramaze landmark by learning landmark-goal vector. Extramaze cues also available for standard place learning, or “cognitive mapping,” but these valid only within each session, as position moved around pool sessions together with landmark. Animals...

The capacity for goal-directed behavior requires not only the encoding of response-outcome relationship but also ability to resolve conflict induced by competing responses. Recent neuroimaging studies have identified prefrontal cortex as critical resolving between At present, however, much this evidence is indirect, and necessity dorsomedial (dmPFC) function resolution in has been assessed. Here, we develop a rodent paradigm investigate response caused concurrent activation correct incorrect...

The effects of stimulus salience and cue validity in the overshadowing geometric features an enclosed arena by discrete landmarks were investigated rats using water maze paradigm.Experiment 1 established that a rhomboid-shaped acute corner was more salient than obtuse for rats.In subsequent two experiments, trained to find submerged platform either or corner.In addition angle, also signalled concurrent presence landmark which valid Experiment 2. resulted overall geometry learning, effect...

ABSTRACT Rats with lesions of the hippocampus or sham were required in four experiments to escape from a square swimming pool by finding submerged platform. Experiments 1 and 2 commenced passive training which rats repeatedly placed on platform one corner—the correct corner—of distinctive walls. A test trial then revealed strong preference for corner but not hippocampal group. Subsequent active being swim resulted both groups acquiring two experiments. In 3 4, solve discrimination between...

Abstract Previous studies have suggested that spatial navigation can be achieved with at least two distinct learning processes, involving either cognitive map‐like representations of the local environment, referred to as “place strategy”, or simple stimulus‐response (S‐R) associations, “response strategy”. A similar distinction between cognitive/behavioral processes has been made in context non‐spatial, instrumental conditioning, definition concerning sensitivity a given behavior expected...

Oxytocin (OT) has been implicated in a variety of mammalian reproductive and social behaviors, the use intranasal OT for clinical purposes is on rise. However, basic actions OT, including rewarding or reinforcing properties drug, are currently not fully understood. In this study, authors investigated whether intranasally administered different nonsocial stimuli such effects variable between male female subjects. Conditioned preference (CSP) conditioned place (CPP) paradigms were used to...

In three experiments, rats were trained to locate a submerged platform in one of the base corners triangular arena above each which was suspended two distinctive landmarks. Experiment 1, it established that these landmarks differed their salience by differential control they gained over behavior after training compound with geometric cues. 2, shown locating beneath less salient landmark potentiated learning based on geometry compared for provided ambiguous information about location...

Studies of spontaneous behaviour to assess memory are widespread, but often the relationships objects contexts and spatial locations poorly defined.We examined whether object--location was maintained following global, not local, changes geometric shape an arena.Rats explored two trial--unique in a distinctively shaped arena before being exposed identical copies one these different physical location.Rats preferentially that were novel relation their local context rather than identifying both...

The cognitive map has been taken as the standard model for how agents infer most efficient route to a goal location. Alternatively, path integration - maintaining homing vector during navigation constitutes primitive and presumably less-flexible strategy than mapping because relies primarily on vestibular stimuli pace counting. historical debate whether complex spatial is ruled by associative learning or mechanisms challenged experimental difficulties in successfully neutralizing...

The ability of rats to solve a discrimination between two objects that differ in length was investigated five experiments. Using rectangular swimming pool, Experiment 1 revealed it is easier locate submerged platform when near the center long rather than short wall. For Experiments 2-4, were black or white panels pasted onto gray walls square with opposing and remaining walls. placed middle panel. This effect found twice (Experiments 2-4) four times (Experiment 4). 5 demonstrated can 15 45...

We examined the role of hippocampus and dorsolateral striatum in representation environmental geometry using a spontaneous object recognition procedure. Rats were placed kite-shaped arena allowed to explore two distinctive objects each right-angled corners. In different room, rats then into rectangular with identical copies one from exploration phase, adjacent corners that separated by long wall. Time spent exploring these was recorded as measure memory. Since both locations respect room...

Abstract This study investigated how goal‐directed and habitual behaviors recover after extinction within the context of resurgence effect, a form relapse induced by removal or worsening alternative reinforcement. Rats were trained to press target lever with one reinforcer (O1) for either minimal (4) extended (16) sessions. An test completion O1 devaluation confirmed that training formed behaviors, respectively. Then, pressing an was reinforced second (O2) while response placed on...

Previous studies have shown that low doses of ketamine, an N-methyl-D-aspartate receptor antagonist, produce aberrantly strong internal representations associatively activated but absent stimuli in humans and nonhuman animals, suggesting the validity ketamine treatment as a preclinical model positive symptoms schizophrenia, including hallucinations delusions. However, whether acute also impairs ability to ignore present informationally redundant stimuli, which is another hallmark remains...

In recent years, there have been significant advances in our understanding of the positive symptoms schizophrenia, such as hallucinations and delusions. This progress has significantly aided by use associative learning-based approaches human subjects preclinical animal models. Here, we first review experimental research focusing on abnormal processing absent stimuli using three different conditioning phenomena: conditioned hallucinations, mediated conditioning, trace conditioning. We then...

In 4 experiments, rats had to discriminate between the lengths of 2 objects same color, black or white, before a test trial with but opposite color.The experiments took place in pool from which escape by swimming 1 submerged platforms.For Experiments and 2, platforms were situated near centers panels length, not another, that pasted onto gray walls square arena.The acquired preference for correct length was eliminated changing color panels.In Experiment 3, middle long rectangular pool, they...

Two groups of rats in Experiment 1 were required to escape from a square pool by swimming 2 submerged platforms that situated beside the centers opposite walls. To help find platform, black panels equal width pasted middle walls adjacent platforms. The was 50 cm for Group 50, and 100 100. Test trials then conducted same pool, but with removed 50-cm panel on wall 100-cm wall. expressed stronger preference than during test, whereas similar both panels. Thus degree generalization short long...