The aim of this study was to compare the learning performance of Wistar rats in passive avoidance box and open field behavior. Animals were placed in the center of the open field and their behavior was manually recorded for 5 min. Two latency periods, first motion, and exit to the center, the number of inner and outer squares crossed, grooming activity, the number of rearing in the center of th...

A B S T R A C T Introduction: Diabetes mellitus is accompanied with disturbances in learning, memory, and cognitive skills in the human society and experimental animals. Due to anti-diabetic and antioxidant activity of Rumex patientia (RP), this research study was conducted to evaluate the efficacy of chronic Rumex patientia feeding on alleviation of learning and memory disturbance in streptozo...

intracerebroventricular (icv) injection of streptozotocin (stz) causes cognitive impairment in rats. the beneficial effect of crocus sativus l. extract (cse) was evaluated on icv stz-induced learning, memory, and cognitive impairment in male rats. for this purpose, rats were injected with icv stz bilaterally, on days 1 and 3 (3 mg/kg). the stz-injected rats received cse (60 mg/kg; i.p.) every o...

introduction: zinc is an essential rare element that plays an important role in synaptic plasticity and modulation of the activity of central nervous system and is involved in learning and memory. increasing zinc intake may protect against conditions associated with zinc deficiency, such as diabetes. some studies have revealed that zinc deficiency in diabetic subjects is due to hogher excretion...

background and objective: intracerebroventricular (icv) injection of streptozotocin (stz) causes cognitive impairment in rats. the beneficial effect of saffron main component, safranal was investigated on icv stz-induced learning, memory, and cognitive impairment in male rats. materials and methods: for this purpose, rats were injected with icv stz bilaterally, on days 1 and 3 (3 mg/kg). the st...

The role of the magnocellular reticular formation (MGRF) of the brainstem on learning and memory was examined in memory-deficient mice with spontaneous spongy degeneration in the brainstem (senescence-accelerated mouse, SAMP8) and control mice (accelerated-senescence resistant mouse, SAMR 1). SAMP8 showed spontaneous age-related impairment of learning and memory, as determined by passive and ac...

The extent to which we learn from positive and negative outcomes of decisions is modulated by the neurotransmitter dopamine. Dopamine neurons burst fire in response to unexpected rewards and pause following negative outcomes. This dual signaling mechanism is hypothesized to drive both approach and avoidance behavior. Here we test a prediction deriving from a computational reinforcement learning...

The lateral habenula (LHb) is an epithalamic structure involved in signaling reward omission and aversive stimuli, and it inhibits dopaminergic neurons during motivated behavior. Less is known about LHb involvement in the acquisition and retrieval of avoidance learning. Our previous studies indicated that brief electrical stimulation of the LHb, time-locked to the avoidance of aversive footshoc...

The present study investigated the effects of approach versus avoidance motivation on declarative learning. Human participants navigated a virtual reality version of the Morris water task, a classic spatial memory paradigm, adapted to permit the experimental manipulation of motivation during learning. During this task, participants were instructed to navigate to correct platforms while avoiding...

The hippocampus has been implicated in anxiety disorders and post-traumatic stress disorder (PTSD); human studies suggest that a dysfunctional hippocampus may be a vulnerability factor for the development of PTSD. In the current study, we examined the effect of hippocampal damage in avoidance learning, as avoidance is a core symptom of all anxiety disorders. First, the effect of hippocampal dam...