Naps Are Better Than Caffeine
Hoping to improve your tennis serve? It’s probably better to catch
a few winks than load up on java after a lesson, results of a
NIMH-supported study suggest. Caffeine impaired such motor learning
and verbal memory, while an afternoon nap benefited all three types
of learning tested by Sara Mednick, Ph.D., and colleagues at the
University of California, San Diego. The researchers report on
their findings in the November issue of Behavioural Brain Research.
Ninety percent of Americans use caffeine daily, some substituting
it for sleep. While the stimulant enhances alertness and
concentration, it’s been unclear whether it also helps learning and
memory. By contrast, daytime naps, like nighttime sleep, benefit
both alertness and memory, Mednick and colleagues have shown in a
series of studies.
In this first head-to-head day-time comparison, 61 participants
trained in the morning on verbal memory, motor, and perceptual
learning tasks. After lunch, one group napped (60-90 min), while
two other groups listened to a book on tape and received a pill
containing either the caffeine equivalent of a little less than a
Tall Starbucks brewed coffee (200mg) or a placebo. Later in the
afternoon, the three groups were tested to see how well they had
learned the tasks.
==================================================
Learn more in Trevor Ponder’s training programs:
http://www.memoryonfire.com/memoryonfireaudio.html – audio book
http://www.elementsofmemory.com/elementsbook.html – PDF book
==================================================
Findings of This Study
The nap group performed significantly better on a finger tapping
motor task and in recalling words, than the caffeine group. The nap
group also trumped the other groups on a texture discrimination
task of perceptual learning. The placebo group performed better
than the caffeine group on all three tasks. Curiously, just
thinking that the pill might contain caffeine — the placebo effect
— helped as much as a nap on the motor task.
Significance
Evidence suggests that caffeine interferes with tasks that require
processing explicit, as opposed to implicit, information – like
recalling a specific word, versus remembering how to type or ride a
bike. Studies show that consolidation of such explicit verbal
memory during sleep depends on lowered levels of the chemical
messenger acetylcholine in the brain’s memory hub. Yet, by blocking
activity of a natural sedative chemical, caffeine boosts
acetylcholine in this hub.
==================================================
Learn more in Trevor Ponder’s training programs:
http://www.memoryonfire.com/memoryonfireaudio.html – audio book
http://www.elementsofmemory.com/elementsbook.html – PDF book
==================================================
“This increase in acetylcholine by caffeine may impair the
consolidation process by blocking replay of new memories,” proposes
Mednick. “Consistent with this, we found that the greater the
explicit component of each task, the worse the caffeine group
performed.”
What’s Next?
“Such an impairment of performance runs counter to society’s
assumption that caffeine typically benefits cognitive performance,”
she notes. “Apparent improvements with caffeine might actually
reflect a relief from withdrawal symptoms. Just as no medicinal
alternative to a good night’s rest has been discovered, so too
caffeine, the most common pharmacological intervention for
sleepiness, may not be an adequate substitute for the memory
enhancements of daytime sleep, either.”
Mednick and colleagues are using new pharmacological agents found
to selectively enhance particular stages of nighttime sleep to see
if they can enhance memory consolidation during daytime naps. Brain
imaging will pinpoint effects on neural circuits. These studies of
pharmacologically enhanced naps could lead to improved treatments
for memory impairment in mental disorders, based on manipulations
of sleep, say the researchers.
==================================================
http://www.memoryonfire.com/memoryonfireaudio.html
http://www.elementsofmemory.com/elementsbook.html
http://trevorponder.com
==================================================
…………………………….
