The Wernicke-Kleist-Leonhard "short-circuiting": a missing link between attention deficit hyperactivity disorder,...

According to the Wernicke-Kleist-Leonhard (WKL) School of Psychiatry, human actions could be categorized into spontaneous, expressive, reflex, and reactive. The so-called short-circuit movements represent a pathological exaggeration of immediate reactions to sensory impressions, such as sudden or threatening stimuli. "Short-circuiting" was deemed of utmost importance for the diagnoses of several WKL endogenous psychoses, such as hyperkinetic motility psychosis, periodic catatonia, and proskinetic catatonia. We suggest that short-circuit movements may be an under-reported behavioral phenotype that may cut across different phenotypes of non-psychotic DSM-IV-TR disorders, such as attention deficit hyperactivity disorder (ADHD), Tourette's syndrome (TS), and obsessive-compulsive disorder (OCD). Several features of a neuropsychiatric syndrome seen in the coarse frontal lobe disease ("complex psychomotor release phenomena") may provide a neurological working model for "short-circuiting" in ADHD, TS, and OCD. Further, short-circuit movements may be associated with different degrees of serotonergic, dopaminergic, and glutamatergic dysfunctions. Indeed, although there are a growing number of studies reporting successful treatment of short-circuit movements with topiramate and other glutamatergic antagonists, treatment response to drugs based on serotonergic or dopaminergic mechanisms of action is more uncertain and, sometimes, detrimental, leading to an aggravation of pathological behavior. A resurgence of the interest on the descriptive psychopathology of the WKL short-circuit movements could provide a new conceptual framework for the studies on the neurobiology of volitional disorders.