Send to

Choose Destination
Lancet Neurol. 2006 Jun;5(6):513-24.

Startle syndromes.

Author information

Department of Neurology, Academic Medical Centre, University of Amsterdam, Amsterdam, Netherlands.


Startle syndromes consist of three heterogeneous groups of disorders with abnormal responses to startling events. The first is hyperekplexia, which can be split up into the "major" or "minor" form. The major form of hyperekplexia is characterised by excessive startle reflexes, startle-induced falls, and continuous stiffness in the neonatal period. This form has a genetic basis: mutations in the alpha1 subunit of the glycine receptor gene, GLRA1, or related genes. The minor form, which is restricted to excessive startle reflexes with no stiffness, has no known genetic cause or underlying pathophysiological substrate. The second group of startle syndromes are neuropsychiatric, in which excessive startling and various additional behavioural features occur. The third group are disorders in which startling stimuli can induce responses other than startle reflexes, such as startle-induced epilepsy. Diagnosis of startle syndromes depends on clinical history, electromyographic studies, and genetic screening. Further study of these disorders may enable improved discrimination between the different groups.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center