Triggers that can lead to sleepwalking danger at bedtime - The Times 18th April 2008

Sleepwalking or somnambulism refers to recurrent episodes of abnormal, complex behaviour that occur during “slow-wave sleep” during the first third of the night. The person typically leaves the bed and is active in a confused and disorientated state. They move slowly and clumsily and may injure themselves. Episodes sometimes begin “sleep terror”, which ranges from an increased heart rate to shouting and screaming. In these instances movements are much more rapid and may involve rushing into walls, through windows or out into the street.

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