Staddon and Higa's (1999) trace-strength theory of timing and memory for event duration can account for pigeons' bias to "choose short" when retention intervals are introduced and to "choose long" when, following training with a fixed retention interval, retention intervals are shortened. However, it does not account for the failure of pigeons to choose short when the intertrial interval is dis...

Memory of 3 capuchin monkeys, Cebus apella, was tested with lists of 4 travel-slide pictures and different retention intervals. They touched different areas of a video monitor to indicate whether a test picture was in a list. At short retention intervals (0 s, 1 s, 2 s), memory was good for the last list items (recency effect). At a 10-s retention interval, memory improved for 1st list items (p...

introduction: previous studies have indicated that stress levels of glucocorticoid hormones induce impairment of long term memory retrieval, but the underlying mechanisms (genomic or non-genomic) are not clear. to clarify this issue, we investigated the involvement of brain corticosteroid receptors and protein synthesis in the glucocorticoid-induced impairment of memory retrieval. methods: 140 ...

It is well established that male rats have an advantage in acquiring place-learning strategies, allowing them to learn spatial tasks more readily than female rats. However many of these differences have been examined solely during acquisition or in 24h memory retention. Here, we investigated whether sex differences exist in remote long-term memory, lasting 30d after training, and whether there ...

Introduction: Recent studies suggest that glucocorticoids modulate memory reconsolidation. Moreover, cholinergic system is involved in memory reconsolidation. Since glucocorticoids interact with brain cholinergic system in modulating memory processing, we investigated whether glucocorticoid influences on the reconsolidation of emotionally arousing training depend on the cholinergic system...

Introduction: Previous studies have indicated that stress levels of glucocorticoid hormones induce impairment of long term memory retrieval, but the underlying mechanisms (genomic or non-genomic) are not clear. To clarify this issue, we investigated the involvement of brain corticosteroid receptors and protein synthesis in the glucocorticoid-induced impairment of memory retrieval. Methods: 140 ...

Historically, psychologists and neuroscientists have distinguished between processes supporting memory for events across retention delays of several seconds (short-term memory, STM), and those supporting memory for events across longer retention delays of minutes or more (long-term memory, LTM). Dissociations reported in some neuropsychological studies have contributed to a popular view that th...

Background. Sleep is assumed to be a critical factor for human physiological and cognitive function. Lack of sleep is a common condition in daily life. Objectives. The purpose of this study was to evaluate the effects of 24-hour sleep deprivation on cognitive and motor skills in university students. Methods. The participants were volunteers that consisted of 290 male students aged 19-25 years...

The α2 adrenergic receptors which abundantly express in the CA1 region of the hippocampus play an important role in the regulation of sleep and memory retention processes. Based on the available evidence, the aim of our study was to investigate consequences of the activation and deactivation of CA1 α2 adrenergic receptors (by clonidine and yohimbine, respectively) on the impairment of memory re...