The general insomnia definition can sometimes be quite vague. Generally speaking it's when a person can't get to sleep or doesn't get restorative sleep. There are 3 main types of insomnia...

1. Insomnia Definition
What comes to mind when asked the question, "What is insomnia?" The
general insomnia definition is defined by an individual's report of sleeping
difficulties. Another definition of insomnia is when a person has difficulties
initiating and/or maintaining sleep. A person experiencing insomnia
doesn't get the restorative functions usually associated with sleep and
therefore experiences loss or impairment of functional ability throughout
the day. People experiencing an inability to deal with stress for a period
longer than a month may also experience bouts of insomnia.
Doctors associate a variety of signs and symptoms with insomnia.
Oftentimes, the symptoms of insomnia are associated with mental
conditions such as dementia, bipolar disorder, anxiety disorders, post
traumatic stress disorder or medical conditions such as rheumatoid
arthritis or hyperthyroidism.

2. Dictionary Insomnia Definition
Insomnia can be classified into three categories: transient, acute, and
chronic.
Transient insomnia is when the
symptoms of insomnia last for
less than a week. It can be
caused by another disorder or
by changes in your sleep
environment, stress, a
difference in the timing of your
sleep, or by severe depression.
The consequences of this lack of
sleep are sleepiness and
impaired physical and mental
performances (psychomotor
retardation) - similar to the
effects of sleep deprivation.
Acute insomnia is when an
individual has trouble sleeping
consistently for a period less
than a month.
Chronic insomnia may be caused by another disorder and its effects
vary depending on the cause. This type of insomnia may include
mental fatigue, muscular fatigue, or even hallucinations. It lasts for
more than a month, and some people who live with this kind of
disorder may experience double vision or a visual slow down of
events - seeing things as if they are happening in slow motion.

3. Not being able to get to sleep at night can be
a horrible experience - at night as well as
throughout the following day. But it doesn't
have to be that way - sometimes all it takes is
a few lifestyle adjustments. Learn what you
need to know to instantly fall asleep each
night in the sleep ebook,
Get to Sleep Now! 39 Ways to Guarantee Your ZZZs.
People experiencing insomnia don't feel refreshed when they wake up. It
affects their ability to actually get to sleep as well as the quality of the sleep
they do get. Unfortunately, it's a fairly common disorder which affects
millions of people worldwide. Because insomnia can have long term
physical and emotional effects, early diagnosis of the disorder itself as well
as the cause(s) of the disorder is essential.
If you suffer from insomnia or believe
you're suffering from insomnia, there are Related Articles
many things that you can do to alleviate
or cure the problem. However, before Why We Sleep
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insomnia definition, learn more about What is Narcolepsy?
what causes insomnia.