Passive avoidance learning occupies a central role in accounts of disinhibited behavior, ranging from psychopaths' persistent criminality (Hare 1970) to extraverts' gregariousness (Gray, 1972). To explore the mechanism underlying passive avoidance deficits, we assessed the relation of extraversion, neuroticism, and response latency after punishment to passive avoidance learning by using two suc...

Lithium is a drug used for the treatment of bipolar disorder. It has several mechanisms of action, and recently it is shown that lithium can antagonize the 5-HT1B/1D serotonin receptors. Sumatriptan is a 5-HT1B/1D receptor agonist used for the treatment of cluster headaches and migraine which might cause memory impairment as a potential side effect. In this study, effects of lithium on sumatrip...

BACKGROUND AND PURPOSE We investigated changes in locomotor activity, passive avoidance task performance, and hippocampal CA1 neurons induced by cerebral ischemia in Mongolian gerbils to examine the relation between these behavioral changes and CA1 neuronal damage. METHODS Spontaneous locomotor activity was measured using the open field method before and 1, 3, 7, 14, or 28 days after 1- to 5-...

Previous work has shown that the effect of opioid-receptor blockade on memory modulation is critically dependent upon the intensity of stress. The current study determined the effect of adrenergic-receptor blockade on memory modulation under varied levels of stress and then compared the effect of adrenergic-receptor blockade under intense stress to that of a) opioid-receptor blockade and b) con...

BACKGROUND This study aimed to evaluate the effect of two weeks oral administration of pomegranate seed extract (PGSE) on active and passive avoidance memories after permanent bilateral common carotid arteries occlusion (2CCAO) to induce permanent cerebral ischemia in adult female rats. METHODS Seventy adult female Wistar rats (250 ± 20 g) were used. Animals were divided randomly into seven g...

Background: Progesterone as a reproductive hormone is studied in the brain structure. New studies are mainly about systemic injection and have shown that the progesterone has different effects on memory. But it is not clear if hippocampus is mediator of progesterone in reinforcement of memory and learning. So, the effects of intra-hippocampal injection of progesterone on passive avoidance memor...

Individuals use both passive and active defensive responses to environmental threats. Much is known about the neural circuits of passive defensive responses (e.g., freezing), but less is known about the substrates of active defensive responses (e.g., avoidance). We developed an active avoidance task in which rats learn to avoid a tone-signaled footshock by stepping onto a nearby platform. An ad...

BACKGROUND AND PURPOSE The purpose of the present study was to determine whether exposure to stress or elevated corticosterone concentrations in the days preceding cerebral ischemia exacerbates ischemic injury as assessed by histological and behavioral outcomes. METHODS For 7 consecutive days, male C57/BL6 mice were exposed to social stress for 45 minutes or injected with 1 mg/kg corticostero...

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 (...

This study examined behavioral effects mediated by NMDA (N-methyl-D-aspartic acid) receptors in 12-week streptozotocin (STZ)-induced diabetic rats. Effects of an NMDA receptor agonist on behavior in the open field test, passive avoidance test and T-maze were examined in control groups of rats and in rats with diabetes mellitus (DM). We have used 116 rats for experiments. Experimental type I dia...