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Memory and DHEA
Studies have suggested that DHEA administration can improve memory
performance as well as neuronal plasticity.
DHEA has been shown to improve measures of cognitive function, such as
memory, in laboratory studies. Abnormal balances in the brain between DHEA-S
and cortisol have been shown to decrease brain function.
Clinical Studies
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In a medical school study,
31 elderly people with memory loss were given DHEA by mouth daily for 3
months.
There were no side effects and, when compared with similar
patients who received only a placebo, those receiving DHEA performed
better on tests of mental function and memory.
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A
case report in 1990 of a 47 year old woman with a 20 year history of
treatment-refractory learning and memory dysfunction and with low baseline
of DHEA(S) levels (177). She demonstrated improved verbal recall and
recognition and normalization of EGG and P300 brain electrophysiology in
response to open-label DHEA raging from 12.5mg/kg to 37mg/kg for 2 years.
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In contrast to the non-beneficial effects of
DHEA on memory in the elderly, a randomised UK study found that a 7-day
course of DHEA (150 mg twice daily) improved
episodic memory
in healthy young men. In this study, DHEA was also shown to improve
subjective mood and decrease evening
cortisol
concentration, which is known to be elevated in
depression.
The effect of DHEA on memory appeared to be related to an early activation
of the
anterior cingulate
cortex (ACC) and it was suggested this was due to neuronal
recruitment of the steroid sensitive ACC that may be involved in
pre-hippocampal memory processing.
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The effect of dehydroepiandrosterone (DHEA) on
recognition memory decision processes and discrimination in postmenopausal
women.
An 8-week placebo-controlled, double-blind experiment in which 30 women
(ages 39-70) received a 50-mg/day oral dose of DHEA for 4 weeks
demonstrated that DHEA made subjects more conservative (i.e., less likely
to call test items "old") in their recognition memory decisions and
enhanced recognition memory discrimination for items presented briefly.
The former result may reflect an empirical regularity in which recent
strong memory experiences make participants more conservative. The later
result may reflect the effect of DHEA on visual perception, with
consequent effects on memory. These results suggest the methodological
importance of focusing on decision processes when examining the effects of
hormones on memory.
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