The most common sleep problem is insomnia, reported by about 1/3 of the adult population. Of those who experience it, half say it occurs regularly. All told, it’s estimated that at least 30 million adults in the U.S. experience severe chronic insomnia. Yet 85% of insomniacs never seek any type of medical help for their condition. (Jacobs, 1998)
Types of insomnia
There are 3 basic types of insomnia that people suffer from:
- Sleep-onset insomnia
This type is probably the most well known. It means that when people go to bed they have a hard time falling asleep. Once they actually get to sleep they may sleep fine, but for them just falling asleep has turned into an agonizing, time-consuming chore.
- Sleep-maintenance insomnia
This occurs when people wake up during the middle of the night and then have a hard time falling asleep again. Sometimes they lying awake for 30 minutes or more. This can also involve someone who wakes up too early and can not fall asleep again, losing an hour or two of sleep that night.
- Poor quality sleep
Though these insomniacs do not have any conscious memory of waking during the night, they wake up non-refreshed as if they aren’t getting enough sleep.
How to tell if you have insomnia
Not every little difficulty falling asleep qualifies as insomnia. In order to meet the clinical diagnosis, your sleep difficulties must create problems that extend into the next day, such as irritability, fatigue, drowsiness, or impaired functioning or performance. As stated by Gregg Jacobs, Ph.D., “If you have trouble falling asleep or staying asleep at night but feel alert and rested during the day, you are not an insomniac but a person who just requires less sleep.” (1998, p. 23) To find out about yourself, try adjusting your schedule a bit and see if these problems disappear.
Studies have found that the average sleep-onset insomniac will take around 1 1/4 hours to fall asleep. Sleep maintenance insomniacs will spend about the same amount of time lying awake at night. (ibid) On average, chronic insomniacs average around 5 1/2 hours of sleep – two hours less than normal sleepers.
What causes insomnia?
There are many things that can cause insomnia. Acute cases of sleeplessness may even be a natural coping mechanism. As Dr. Jacobs writes: “Occasional bouts of insomnia are normal and inevitable reactions to significant life events such as losses like death or divorce; family or work-related stressors; health problems, hospitalizations, or recovery from surgery; and relationship changes. Insomnia is such a customary reaction to these stressful life events (only 5 percent of adults report that they have never experienced insomnia) that some sleep experts surmise insomnia may serve an adaptive purpose in that it compels us to spend extra time thinking about and coping with these stressors.” (Jacobs, 1998, p. 25) These cases of event-related insomnia will usually abate within a few weeks.
On other occasions, however, people suffer insomnia without any triggering events, or they continue to be stricken with sleeplessness for long periods of time. In these cases, other factors likely have played a role.
The biological basis for insomnia
Research has found that those who suffer from insomnia may show slightly altered biological patterns in their sleep. For example, studies show that insomniacs have greater physical body tension throughout the night than do good sleepers, as measured by a faster heart rate and more muscle tension. They also have faster brain-wave patterns, consistent with heightened mental activity. (Jacobs, 1998) It’s unclear whether this is a cause of insomnia or merely an effect.
Other studies have found that the body temperature of insomniacs drops about 3 hours later than good sleepers, making it more difficult to fall asleep. It also doesn’t seem to drop as much. If you remember what we discussed in the biology of sleep, this decrease in body temperature is an important marker that helps bring on sleep.
As Dr. Jacobs says, “Collectively, the research on the physiology of insomnia suggests that insomniacs have improperly balanced sleep and wakefulness systems: the former is too weak, the latter too strong, and sleep is too easily disturbed.” (ibid, p. 25) Thus these people would find it harder to fall asleep and would stir more easily, waking during the night and then being unable to sleep again.
The environmental causes of insomnia
Everything from our work schedule (shift workers suffer more sleep problems) to our daytime activities (less active people have a harder time with sleep) to the conditions we go to rest in can influence how quickly we get to sleep. These things will be addressed in further detail later in the book.
Mental and behavioral causes of insomnia
Other issues aside, the most influential factor in insomnia is typically the way in which a person approaches sleep. As Dr. Jacobs writes, “Thoughts and behaviors, not medical problems, play the primary role in most cases of chronic insomnia.” (ibid, p. 27) We have trouble falling asleep, and so then we dwell on it. This anxiety makes it harder to put our mind to rest the next night, and so a pattern begins to emerge. If this goes on for too long, we can develop the habit of sleeplessness just like we might form a habit of smoking cigarettes. Or we may engage in behavior that make sleeping more difficult, such as using caffeine or alcohol late at night, or stressing over work problems while playing computer games late at night.
This is why cognitive behavioral therapy is often the treatment of choice for doctors treating insomnia: Fix these mental and behavioral issues and you can usually tip the balance enough that it will become easier to sleep again.
The link between depression and insomnia
Certain psychological disorders – depression in particular – can also contribute to insomnia. Depressed people have been found to have reduced deep sleep, increased light sleep, and excessive REM sleep. They enter REM sleep earlier in the night and spend more time there. Depressed people tend to show a flattened body temperature rhythm, and the lack of activity that is common to depression can further fuel the problem. Research has even suggested that the dream content of those suffering is more depressing. (Jacobs, 1998)
However, this hardly means that insomnia and mental health disorders go hand in hand. Studies find most patients with chronic insomnia DO NOT have a diagnosable psychiatric disorder such as depression or anxiety. So while these conditions may worsen sleeplessness, they are seldom the exclusive cause of it.