<unk>  is a symptom of certain nervous disorders or conditions such as Parkinson's disease and epilepsy. It is also a characteristic symptom of cocaine withdrawal, as well as one of the features of catatonia. It can be caused by schizophrenia treatment with anti-psychotics, such as haloperidol, and by the anesthetic ketamine. Protein kinase A has been suggested as a mediator of cataleptic behavior. Unsuggested waxy<unk> , sometimes accompanied by spontaneous anesthesia, is seen as an indicator of hypnotic trance. Suggested or induced rigid<unk> , of extended limbs or even the entire body, sometimes tested with heavy weights, has been a staple of stage hypnosis shows and even academic demonstrations of hypnotism since the late 18th century, as proof of extraordinary physical abilities possible in trance states. Such demonstrations have also been performed by Asian martial artists and attributed to the pneumatic vital energy known as qi.
Catalepsy
Clonus
Catatonia
Pallor
Snatiation
Cataplexy
Stuttering
Paratonia