How does sleep and lack thereof affect your brain?

Dr. Craig Hudson, MD | February 10, 2017


Scientists are still in the process of unravelling how the brain functions, but one thing we do know is that the brain requires sleep, and a lack of sleep can result in a decrease in brain function.

Sleep and Memories

Many researchers have linked sleep deprivation to a decrease in activity in the hippocampus, with the findings of several studies indicating that sleep has a vital role in the consolidation of new memories.  One study by Yoo et al. published in an issue of Nature Neuroscience concluded that getting restful sleep before and after learning new information improves the likelihood of retaining that information.  Inadequate amounts of sleep can disrupt our capacity for having new experiences committed to our long-term memory.

Maintaining Cognitive Function

There is plenty of anecdotal evidence and academic research that documents the effects of sleep deprivation on our brain’s capacity for cognitive function. Our multi-tasking abilities, perception, reaction times and alertness all suffer without adequate sleep. Some will also experience a tendency to be more careless and reckless in decision-making. In terms of the physical impact that causes these issues, researchers believe that the effects of sleep deprivation on the prefrontal cortex is to blame.

The impairment experienced by this region of the brain can also decrease cognitive function in more abstract areas like creativity. Functions that are closely tied to emotional responses are believed to be particularly susceptible to sleep loss related deterioration.

Emotions Run High

If you have ever known someone to be more irritable, stressed and angry after experiencing a stretch of sleeplessness, maybe you can take comfort in knowing it is very likely that lack of sleep was responsible for this behavior. Insomnia is frequently linked to heightened feelings of negative emotions, especially in stressful situations.

A study published in Emotion by authors Minkel et al. from the University of Pennsylvania’s Department of Psychology found that participants who were sleep-deprived expressed feeling more anxiety and anger following exposure to mildly stressful conditions than their well-rested peers. When exposed to ‘high stress’ situations, the participants reported about the same level of stress as they did during the less stressful situations. From these results, researchers determined that a lack of sleep “lowers the psychological threshold for the perception of stress from cognitive demands.”

Sleep affects the brain in a multitude of ways. There is a lot we do not yet know about how the brain relies on sleep.

If you have experienced any of the symptoms discussed in this post, or you are struggling with insomnia, contact your family doctor.