Many people drink coffee to wake up in the morning or to get an energy boost in the middle of the day, but a new study suggests that caffeine has a deeper effect on the brain than is commonly thought. According to the study, caffeine may improve communication between the sensory and motor systems in the brain – a mechanism linked to concentration, information processing, and even long–term neurological health.
The study examined a brain process called SAI, a metric used to evaluate the brain's ability to integrate sensory information with movement. This ability is considered important for normal cognitive function, and tends to be impaired in degenerative diseases such as Alzheimer's and Parkinson's.
As part of the study, 20 healthy young adults participated and received 200 milligrams of caffeine – an amount equivalent to about two cups of coffee – or a placebo. The researchers used transcranial magnetic stimulation (TMS) technology to examine how caffeine affects brain activity.
The results showed that after caffeine consumption, there was a significant improvement in communication between the sensory and motor areas of the brain. The researchers estimate that the effect is related to the blocking of adenosine receptors in the brain, an action that increases the release of acetylcholine – a neurotransmitter important for memory, attention, and information processing.
According to the researchers, this is an interesting finding because impairment of the acetylcholine system characterizes various degenerative diseases. Previous studies have even shown that drugs that increase acetylcholine activity may improve brain functions in Alzheimer's patients.
However, the researchers emphasize that it should not be concluded from the study that coffee prevents dementia. This was a short–term study that examined only healthy young adults, and therefore it is still unclear how caffeine consumption affects the brain over years or at an older age.
They also mention that not everyone responds to caffeine in the same way. Some of the participants reported sleep disturbances when they consumed caffeine less than six hours before bedtime, so it is recommended to prefer drinking coffee during the morning or early afternoon hours.
The study adds to the growing body of evidence that coffee has complex effects on the brain, beyond the familiar feeling of alertness.