This is a type of reflex epilepsy in which seizures are provoked by loud noises or sudden surprises.
Most patients with startle epilepsy are only sensitive to one sensory modality (i.e. temperature, taste, sound, pressure); however, it is the unexpected nature of the stimulus, rather than the sensory modality, that characterizes startle epilepsy.
These seizures usually last less than 30 seconds. The seizure begins with a startle response, followed by a brief tonic phase.
Patients sometimes fall to the ground and experience clonic jerks. Responsiveness to the stimulus decreases as a result of repeated exposure to the stimulus. Spontaneous seizures also occur in patients with startle epilepsy, but are infrequent in most cases.
People with startle epilepsy usually have static cerebral lesions and developmental delay. For many people, half of the body is partially paralysed and it is the weak side of the body that is primarily involved in thestartle seizures.
Startle epilepsy is often associated with disorders such as Down syndrome and cortical dysplastic lesions.