In discrete-trial avoidance conditioning to an external warning signal, the level of conditioning depended upon how much immediate change in the CS was effected by responding. The greater the change, the better the conditioning; this was interpreted in terms of the amount of reward for avoidance. A 2nd experiment showed that even when the response did not remove the warning signal, the occurren...

introduction: lower level of estrogen hormone is considered as an important factor for loss of learning and memory in postmenopausal women. although estrogen replacement therapy is used for compensation, but long-term usage of estrogen is associated with a higher risk of hormonedependent cancers. phytoestrogens, due to fewer side effects, have been proposed to prevent menopause-related cognitiv...

PURPOSE Previous studies have shown that physical activity improves learning and memory. Present study was performed to determine the effects of short term and long term treadmill exercise on learning, memory consolidation and retrieval of passive avoidance learning in an animal model. METHODS In this study fifty male Wistar rats with 3-4 months of age were randomly divided into five groups (...

Acquisition of an active bar-pressing avoidance response was investigated in a factorial design with 3, 5 or 9 s CS-US intervals and CSs of 70- or 50-dB of white noise. As the CS-US interval increased the required time to meet the avoidance criterion decreased. The shorter the CS-US interval and the more intense the CS, the shorter the median response latencies observed at the end of the traini...

Injecting tetrodotoxin (TTX) into one hippocampus impaired avoidance of a place defined by distal cues while rats were on a slowly rotating arena. The impairment could be explained by a deficit in memory, navigation, or behavioral inhibition. Here, we show that the TTX injection abolished the ability of rats to organize place-avoidance behavior specifically when distal room and local arena cues...

Recent years have witnessed a re-evaluation of the cognitive capabilities of fishes, including with respect to social learning. Indeed, some of the best experimental evidence for animal traditions can be found in fishes. Laboratory experimental studies reveal that many fishes acquire dietary, food site and mating preferences, predator recognition and avoidance behaviour, and learn pathways, thr...

Two competing theories predict different effects on memory consolidation when the amygdala is inactivated after fear conditioning. One theory, based on studies using inhibitory avoidance training, proposes that the amygdala modulates the strength of fear learning, and post-training amygdala manipulations interfere with memory consolidation. The other, based on studies using Pavlovian fear condi...