Sleep Apnea and Cognition, pt 2

From reading articles, I have found out about many different experiments done to test for deficits in cognitive abilities in sleep apnea patients.

Response Time Experiment:

Sleep apnea patients showed a decrease in speed in simple response time tasks and choice response time tasks. Simple response time tasks are tasks in which one stimulus is given and one specific response is expected. An example would be a task in which a light is the stimulus and every time the subject sees the light go on, he has to press a certain button.

A choice response time task in one in which multiple stimuli are given and each stimulus requires a different response. An example would be a task in which the stimulus is seeing a letter on the screen and the response would be pressing the corresponding letter key on the keyboard. A study done showed that sleep apnea patients had a decreased reaction time for both kinds of tasks.

Short-Term Memory:

On auditory, spatial, or visual short-term memory tasks, the accuracy of the performance of OSA patients has been mixed. However, imaging of the brain has brought clearer results. Sleep deprivation in OSA patients has shown decreased activity in the intraparietal sulcus (IPS), the green line in the picture below. The IPS plays a key role in processing numbers and in visual working memory (I will talk about this in the next post). The reduction in this region of the brain was linked to a reduction in the memory capacity shown by the study.

Mental Arithmetic:

In mental arithmetic studies, sleep deprived patients have had slower performances and more errors. The study shows that small decreases in sleep and disturbed sleep can severely affect performance on tasks similar to the ones done.

Neuroimaging conducted during the serial subtraction task also showed decreases in the prefrontal cortex, the front part of the frontal lobe (shown below), which is responsible for tasks like problem solving and processing complex thoughts. It is also known to play a role in emotions. Imaging also shows abnormal activation of the parietal lobe (shown below), which integrates sensory information.

These are only a few of the many things that are affected by sleep loss and sleep apnea. I will go further into executive function in my next post.

Stay tuned!
Waters, Flavie, and Romola S. Bucks. "Neuropsychological Effects of Sleep Loss: Implication for Neuropsychologists." Journal of the International Neuropsychological Society 17.04 (2011): 571-86. Web. 16 Apr. 2017.