Insomnia or sleeplessness is characterized by an interruption in the regular sleeping pattern, i.e. interrupted sleep that usually lasts for several days.
When sleep-woken disorders first became a topic of interest in the scientific community, the Diagnostic and Statistical Manual of Mental Disorders (DSM) didn't include them.
Mild neurocognitive disorders is often part of a larger cluster of disorders known as the neurocognitive disorders.
Personality disorders are usually long term patterns of thought, feelings and behaviors that differ markedly from what would be expected in most people.
Although there are no absolute criteria as to what constitutes a personality disorder, there are a number of common characteristics that seem to apply more frequently to some people than others.