Some studies have shown that caffeine can improve some types of memory, particularly the global aspects of memory.
More in-depth research shows that the benefit of caffeine on memory is state dependent. This means that caffeine only improves memory if it is used both at the time of taking the information in, and at the time of recalling the information later. If no caffeine is used at the time the information is presented, people perform more poorly if they take caffeine at the time they need to remember the information, and conversely, if they've had caffeine when they take in the information, and they don't have caffeine when they try to remember it, they do worse than if they do have caffeine at the time they need to remember it.
Other studies show that with certain memory tasks, caffeine actually worsens performance. These include poorer performance on tasks of free recall -- remembering information without being prompted. People also recall more false memories when they are under the influence of caffeine, so it can have the effect of stimulating your brain to come up with memories inaccurately.
Effects of Caffeine on the Memory of Older Adults
There has been some encouraging research regarding the use of caffeine in older adults to counteract the natural declines in memory that are associated with age. For example, one study showed that caffeine reduced the afternoon decline in memory experienced by "morning people" -- older adults who generally perform better in the morning than in the afternoon.
However, other research indicates that caffeine is not a reliable way of improving memory in older people. In fact, research has shown that older people perform more poorly on tests of episodic memory after consuming caffeine-containing foods than those who do not. And although there is evidence that habitual caffeine use is associated with a modest advantage in long-term memory, this does not counter age-related memory declines.
As caffeine is an addictive substance, trying to self-medicate what you believe to be a poor memory may actually be making matters worse. For example, caffeine tends to interfere with your sleep, and is followed by a withdrawal period, both of which can cause memory problems.
Talk to your doctor to find out whether you really have problems with your memory, other ways of improving your memory, and what an optimal amount of caffeine would be for you.
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