In humans and animals cognitive training during childhood plays an important role in shaping neural circuits and thereby determines learning capacity later in life. Using a negative feedback learning paradigm, the two-way active avoidance (TWA) learning, we aimed to investigate in mice (i) the age-dependency of TWA learning, (ii) the consequences of pretraining in childhood on adult learning ca...

Title of Document: NEURAL CORRELATES OF APPROACH AND AVOIDANCE LEARNING IN BEHAVIORAL INHIBITION Sarah M. Helfinstein, Ph.D., 2011 Directed By: Professor Nathan A. Fox, Human Development Behavioral inhibition is a temperamental trait characterized in infancy and early childhood by a tendency to withdraw from novel or familiar stimuli. Recent neuroimaging research indicates that BI individuals h...

Previous research across species has shown that the amygdala is critical for learning about aversive outcomes, while the striatum is involved in reward-related processing. Less is known, however, about the role of the amygdala and the striatum in learning how to exert control over emotions and avoid negative outcomes. One potential mechanism for active avoidance of stressful situations is postu...

Although perinatal exposure of female rats to estrogenic compounds produces irreversible changes in brain function, it is still unclear how the amount and timing of exposure to those substances affect learning function, or if exposure alters estrogen receptor α (ERα) expression in the hippocampus and cortex. In adult female rats, we investigated the effects of neonatal exposure to a model estro...

Alzheimer’s disease (AD) is a chronic neurodegenerative disease causing progressive impairment of memory and cognitive function. Streptozotocin (STZ) injection into the brain is known to cause cognitive impairment in rats and is similar to sporadic AD in humans. Several lines of evidence have indicated that an inflammatory process contributes to the pathology of AD. On the basis of the results ...

Alzheimer’s disease (AD) is a chronic neurodegenerative disease causing progressive impairment of memory and cognitive function. Streptozotocin (STZ) injection into the brain is known to cause cognitive impairment in rats and is similar to sporadic AD in humans. Several lines of evidence have indicated that an inflammatory process contributes to the pathology of AD. On the basis of the results ...

Domestic chickens are an established model organism for studies on learning and memory. Commonly, the chicks are used as subjects in several different learning tests, including one trial learning tests. However, for adult laying hens no such one trial learning tests have been established. In particular, there is no test established which focuses on the role of the hippocampus, a brain region, w...

There is strong evidence that two cerebral hemispheres are differentially involved in emotional memory and that amygdala is a key subcortical structure for emotional experience. The present research investigated the possible involvement of lateralization of basolateral amygdala (BLA) and central amygdala (CEA) in place avoidance memory. For this purpose, male Long-Evans rats (280-320 g) were im...

stress has a profound impact on the nervous system and causes cognitive problems that are partly related to the inflammatory effects. besides influencing the content of neurotransmitters, antidepressants such as doxepin are likely to have anti-inflammatory, anti-oxidative, and anti-apoptotic effects. therefore, the present study investigated the effects of doxepin on passive avoidance learning ...

It is widely recognized that the nature and severity of responses to toxic exposure are age-dependent. Using active avoidance conditioning as the behavioral paradigm, the present study examined the effect of short-term methylmercury (MeHg) exposure on two adult age classes, 1- and 2-year-olds to coincide with zebrafish in relatively peak vs. declining health conditions. In Experiment 1, 2-year-...