Hyperekplexia is a genetic condition characterized by an exaggerated startle reaction to sudden loud sounds, movement, or touch. The muscles may stiffen as a result. Hyperekplexia is a rare condition.

A door suddenly slams. A balloon pops without warning. Fireworks explode nearby, and one person barely notices while another instinctively jumps, gasps, or feels their heart race. These reactions are ...

The acoustic startle response is an unconditional reflex manifested as a rapid contraction of facial and skeletal muscles in response to a sudden and intense startling stimulus. Translational research ...