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Abstract:
Abstract: The hormone cortisol is secreted in the body in
response to stress and synthetic forms are commonly prescribed for
ailments (e.g., arthritis). While research at the cellular, neural
systems and behavioral levels demonstrate that cortisol leads to
impairments in brain functioning, the specific effects on neural
and cognitive operations are unclear. Many studies suggests that
cortisol affects the hippocampus and the form of memory that the
hippocampus subserves (explicit memory) to a greater extent than
other neural and cognitive processes. However, some investigations
indicate that areas within the frontal cortex along with other
cognitive processes may also be affected. Through behavioral and
electrophysiological measures (ERP's) that evaluate specific neural
and cognitive functions, this research examines the effects of
cortisol exposure. Participants received 30 mg of cortisol in one
visit and a placebo in the other. They then performed explicit,
working memory and attention tasks while behavioral responses and
brain activity were recorded. Blood pressure, pulse, cortisol and
affect were also monitored. Preliminary analysis indicates that
cortisol impairs explicit memory, but no effects were seen in the
other tasks. Furthermore, the late positive component - an
electrophysiological correlate of explicit recognition memory and
hippocampal function - was also suppressed. These data suggest that
exposure to high levels of cortisol, via medication or stress,
causes selective impairment in explicit memory, and this might be
due to suppression of hippocampal function.
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