Sleep inertia can be described as a physiological state of impaired cognitive and sensory-motor performance that occurs right when waking up. During this transition, an individual will experience feelings of drowsiness, disorientation, and a decline in motor dexterity. Usually this lasts for 15 to 30 minutes after waking. If a person is suffering from sleep deprivation, this condition can last hours. One theory suggests that sleep inertia is caused by the build up of a neurotransmitter called adenosine within the brain during non-REM sleep that leads to feelings of sleepiness.
While sleep inertia is completely normal, it does impact a person’s decision-making abilities and can pose as an occupational hazard due to the cognitive and motor deficits that may be present. Do not drive or operate machinery during when experiencing an episode. Your reaction time and level of concentration is diminished during this time.
How can you combat the impact of sleep inertia? Optimize your sleep quantity and sleep quality. Most adults need seven to nine hours of sleep each night to feel fully rested. If you suffer from any sleep disorders such as sleep apnea, be sure to consult with your doctor and seek treatment. Intervening will improve your sleep quality, which will then end up decreasing morning sleepiness and sleep inertia.
Another smart way to ward off sleep inertia is to time your morning alarm to the end of a sleep cycle rather than in the middle, which is very disruptive. A complete sleep cycle is roughly 90 minutes, so the best time to wake up would be seven and a half or nine hours after you go to bed.
Learn more about the struggle of waking up below!