abstract background and objective: according to the importance of learning and memory in the human life and also unavoidable neural degeneration due to aging, finding new compounds (drugs) against this process is valuable. however, there are many recommendations for herbal medicine and constituents which encouraged us to examine a candidate plant zingiber officinalis for the mentioned purpose. ...

In studies on avoidance learning, a warning signal is followed by an aversive unconditioned stimulus unless the participant performs a designated response. The authors examined whether avoidance behavior can be based on hierarchical knowledge, that is, knowledge about the conditions under which certain relations hold. In the present study, a single avoidance response had different effects depen...

Several studies suggest an opponent functional relationship between the lateral habenula (LHb) and the ventral tegmental area (VTA). Previous work has linked LHb activation to the inhibition of dopaminergic neurons during loss of reward, as well as to deficits in escape and avoidance learning. We hypothesized that a dopamine signal might underlie the negative reinforcement of avoidance response...

Learning how to gain rewards (approach learning) and avoid punishments (avoidance learning) is fundamental for everyday life. While individual differences in approach and avoidance learning styles have been related to genetics and aging, the contribution of personality factors, such as traits, remains undetermined. Moreover, little is known about the computational mechanisms mediating differenc...

Objective. To study the effect of immunomodulators on learning and memory and on cholinergic receptor sensitivity. Methods. Animals were initially treated for a period of 8 days with cyclosporine/levamisole/saline. They were then subjected to passive avoidance training and 48 hrs later, the retention test for the passive avoidance task was conducted. Twenty-four hours after the retention tests ...

In studies on avoidance learning, a warning signal is followed by an aversive outcome (US) unless the participant makes a particular response. Several theories have been developed to try to explain the mechanisms underlying avoidance learning. Surprisingly, stimulus-response (S-R) theories and cognitive theories of avoidance learning have rarely been compared experimentally. These theories diff...

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 (...