Hyperexplexia is a rare autosomal dominant, hereditary, neurological disorder that may affect infants as newborns (neonatal) or prior to birth (in utero). It may also affect children and adults. Individuals with this disorder have an excessive startle reaction to sudden unexpected noise, movement, or touch. Symptoms include extreme muscle tension (stiffness or hypertonia) that can cause the affected person to fall stiffly, like a log, without loss of consciousness. Exaggeration of reflexes (hyperreflexia), and an unstable way of walking (gait) may also occur.
* Stiff muscles * Falling stiffly to the ground without loss of consciousness * Exaggerated reflexes * Unstable gait
* Bell mania * Congenital myopathy * Grand mal seizures * Hyperexplexia - stiff muscles * Meningitis
The treatment of hyperexplexia is relatively uncomplicated and involves the use of anti-anxiety and anti-spastic medicines. However, the disorder is frequently misdiagnosed as a form of epilepsy so that the process of getting an accurate diagnosis may be prolonged.