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...

Interest in instrumental learning in earthworms dates back to 1912 when Yerkes concluded that they can learn a spatial discrimination in a T-maze. Rosenkoetter and Boice determined in the 1970s that the "learning" that Yerkes observed was probably chemotaxis and not learning at all. We examined a different form of instrumental learning: the ability to learn both to escape and to avoid an aversi...

Introduction: Lead (Pb) is a neurotoxin that its different effects on the central nervous system are well-known. Previous studies have reported the potent effects of vitamin C on memory.The present study was undertaken to evaluate the protective effects of vitamin C against leadinduced amnesia. Methods: Male Wistar rats were divided into 4 groups: the control (saline), negative contr...

test anxiety as a common disorder is a physiological condition in which students experience extreme stress, anxiety and discomfort during and/or before taking a test. this kind of anxiety results from the sense of threats like fear of failure, lack of confidence and setting unattainable goals in learning and wishing to be perfect in academic situation. resulting anxiety disrupts attention, memo...

Introduction: In the recent years, the use of several drugs such as cocaine and morphine has reduced, but the use of "club drugs" has increased in many countries. 3, 4-methylenedioxymethamphetamine (MDMA) which has known as ‘ecstasy’ among people has many harmful effects on serotonergic system in the brain. This system is responsible for learning and memory. In this study, we tested sub-acute a...

Recent research has indicated that vicarious learning can lead to increases in children's fear beliefs and avoidance preferences for stimuli and that these fear responses can subsequently be reversed using positive modeling (counterconditioning). The current study investigated children's vicariously acquired avoidance behavior, physiological responses (heart rate), and attentional bias for stim...