Excessive avoidance behavior, in which an instrumental action prevents an upcoming aversive event, is a defining feature of anxiety disorders. Left unchecked, both fear and avoidance of potentially threatening stimuli may generalize to perceptually related stimuli and situations. The behavioral consequences of generalization mean that aversive learning experiences with specific threats may lead...

Morphine’s effects on learning and memory processes are well known to depend on synaptic plasticity in the hippocampus. Whereas the role of the hippocampus in morphine-induced amnesia and state-dependent learning is established, the biochemical and molecular mechanisms underlying these processes are poorly understood. The present study intended to investigate whether administration of morphine ...

Open field activity was studied in Wistar rats. Animals with low scores of ambulatory and rearing behaviours were grouped as hypoactive and those with high scores as hyperactive. Acquisition of active avoidance learning in a shuttle box was studied in the two groups. Hyperactive rats in contrast to hypoactive rats showed a better acquisition of avoidance learning. Learning was suppressed in bot...

Much of the early research in aversive learning concerned motivation and reinforcement in avoidance conditioning and related paradigms. When the field transitioned toward the focus on Pavlovian threat conditioning in isolation, this paved the way for the clear understanding of the psychological principles and neural and molecular mechanisms responsible for this type of learning and memory that ...

One of the most common causes of mortality in acute kidney injury is brain dysfunction. Here we investigated the possible protective effect of erythropoietin (EPO) on cognitive impairments induced by bilateral renal ischemia (BRI). Eighty male Wistar rats were allocated into 8 groups: 1, 2) Sham+V (Vehicle), 3, 4) Sham+EPO, 5, 6) BRI+V, 7, 8) BRI+EPO. The groups followed by the reperfusion per...

The aim of this study was to compare the learning performance of Wistar rats in passive avoidance box and open field behavior. Animals were placed in the center of the open field and their behavior was manually recorded for 5 min. Two latency periods, first motion, and exit to the center, the number of inner and outer squares crossed, grooming activity, the number of rearing in the center of th...

Introduction: Exposure to 3, 4- methylenedioxymethamphetamine (MDMA) could lead to serotonergic system toxicity in the brain. This system is responsible for learning and memory functions. Studies show that MDMA causes memory impairment dose-dependently and acutely. The present study was designed to evaluate the chronic and acute effects of MDMD on spatial memory and acquisition of passive avoid...

objective(s): calcineurin (cn) is a main phosphatase and a critical regulator of cellular pathways for learning, memory, and plasticity. the fk-506 (tacrolimus),a phosphatase inhibitor, is a fungal-derived agent and a common immune suppressant extensively used for tissue transplantation. to further clarify the role of cn in different stages oflearning and memory the main aim of this study was t...