Startles, twitches and clonuses

Abstract

In everyday language the term' startle' suggests a behavioural and emotional reaction of surprise, shock and fear to a sudden, unexpected event. Startles are also considered as a motor response to noxious and painful stimuli aimed at withdrawing from a threat [1]. However, the word 'startle' is not solely linked with fear and pain, as one can also be pleasantly startled by an unexpected but agreeable experience. © 2010 Springer-Verlag Milan.