So, you don't get enough sleep. No big deal, right? You're young and healthy, energy drinks are readily available, and you have a full life to live. You can catch up later.
Wrong. Sleep debts are just as devastating as financial ones. Inadequate rest impairs our ability to think, to handle stress, to maintain a healthy immune system, and to manage our emotions. The higher incidence of accidents during night shift is well documented. Sleepiness can impair a driver just as much as alcohol.
We are all familiar with the post-hibernation grouchiness exhibited by someone getting up after a bad night. Most of us have had the experience of waking up late with no recollection of hearing the alarm or shutting it off. Sleep-deprived people often feel isolated from the world and resentful of the wide-awake.
Chronic sleep loss has been linked to diabetes, high blood pressure, heart disease, premature aging, and weight gain. Worst of all, it can produce symptoms which suggest mental illness.
Lack of restorative sleep can lead to a diagnosis of depression, and some anti-depressants can interfere with sleeping patterns. You don't want to go there. Trying to catch up on the sleep debt by sleep marathons fosters depression as well. Sleep deprivation is sometimes used as a treatment for unipolar depression, which would take you full circle.
Sleep deprivation information was confined to folklore until Dr. William Dement established a sleep laboratory at Stanford University in 1957, followed by the world's first sleep disorders clinic in 1970. He was the first to use the term REM (rapid eye-movement) sleep, and linked psychotic behavior with sleep deprivation.
Since then, improved research techniques have established that sleep is an incredibly complex process, involving the endocrine system as well as the neural net.
Neurons in our brainstem produce nerve-signaling neurotransmitters such as serotonin and norepinephrine, which control alertness and mood. Other neurons at the base of the brain switch off the signals that keep us awake. This may be the effect of adenosine, which builds up in our blood while we are awake, causing drowsiness, and gradually breaks down while we are asleep.
The production of the stress hormone cortisol is inhibited during sleep. Lack of sleep will lead to a build-up which affects our waking behavior and physiology by keeping us in unnecessarily prepared for fight or flight. Sleep is one of the factors regulating the appetite-control hormone leptin. Tired people often experience food cravings which have nothing to do with their nutritional needs.
During non-REM sleep, the blood supply to the brain decreases. During REM sleep, blood flow increases in the thalamus and the primary visual, motor, and sensory cortices, while remaining comparatively decreased in the prefrontal and parietal regions, allowing vivid dreams while dampening our critical ability to evaluate them. It has been suggested that the brains of REM sleep-deprived people will produce waking dream states.
The most recent tool for studying sleep deprivation is functional magnetic resonance imagining (fMRI), which measures the amount of activity occurring in different areas of the brain. At the University of California in San Diego, Dr. J. Gillian compared the brain activity of people who were sleep-deprived for 35 hours, with that of rested subjects. Sleep deprived subjects, who performed more poorly on verbal learning and memory than their wakeful counterparts, exhibited increased activity in the parietal lobes and the prefrontal cortex, while the rested subjects had more activity in their temporal lobes. Sleep deprivation created shifts in brain activity rather than simply decreasing it. This provides new insight into the way the brain processes information, using back-up systems if necessary, and the way sleep, or lack of it, affects brain function.
The clinical issues surrounding sleep deprivation are complicated by the fact that sleep disturbances are regularly associated with psychiatric conditions such as depression, anxiety and psychotic disorders. Although we can't be sure which is the chicken and which is the egg, it is not a comfortable thought that inadequate sleep can trigger manic episodes or a diagnosis of Attention Deficit Disorder.
While the mechanisms governing sleep are not yet fully understood, we can't deny that restorative sleep is vitally important to physical and mental health. The best time to implement improved sleep hygiene practices is now. That involves common-sense behavioral changes like going to bed at the same time each night, exercising daily, and avoiding stimulants and late-night alcohol consumption.
If these don't help, it may be time to see a doctor about conducting a sleep study. If an underlying condition such as sleep apnea is diagnosed and treated, it will improve the qulity of your life and perhaps even save it. If that doesn't improve your mental health, what will?