Stereotyped responding by schizophrenic patients on a two-choice guessing task

Abstract

SynopsisOn each of a sequence of trials subjects had to guess whether a cross would appear on the left or the right side of a computer screen. The sequence of cross positions was random. Normal controls, manic-depressive patients and patients with senile dementia produced relatively random sequences of responses, as did acute schizophrenic patients with positive symptoms. Acute schizophrenic patients with negative symptoms and chronic patients produced more stereotyped sequences with many response alternations (LRLR). Chronic schizophrenic patients with negative symptoms and intellectual deterioration (defect state) produced very stereotyped sequences with many preservations (LLLL). This severe restriction of response sequences is similar to that shown by animals after treatment with amphetamine. It is suggested that it is due to an impairment of a higher order control process which normally inhibits the repetition of sequences of behaviour when these have proved inappropriate.

Recurrent perseveration correlates with abnormal repetitive locomotion in adult mink but is not reduced by environmental enrichment

“…These results, and similar ones obtained after transferring the mink to Enriched housing, provide further support for a widespread relationship between recurrent perseveration and ARB, particularly stereotypy (of which ARL is one type) [22,23,35,36,41]. We used one measure specifically sensitive to repeated responses, and two sensitive to higher order patterns.…”

“…patterning, or non-randomness) within series of responses [23,[60][61][62]. A similar two-choice guessing task [22,63], also known as a "gambling" task, has been adapted for use with laboratory monkeys [64], birds [35,36], and mice [41,43], and we used an analogous task for mink. Subjects chose between two doors (Fig.…”

“…Statistical associations between perseveration -the tendency to inappropriately repeat actions [21] -and ARB provide evidence for this general impairment in behavioural inhibition. For example, in clinical human subjects participating in simple guessing or sequence-generation games, individuals who frequently repeated answers or short response sequences, despite instructions against doing so, also most frequently performed repetitive movements and had particularly circumscribed interests [22,23]. Perseveration has also been elicited in other circumstances known to cause ARB.…”

“…Most exceptions have focused on "recurrent" perseveration, defined as the inappropriate repetition of an already completed response to a subsequent stimulus [42]. This type of perseveration correlated positively with repetitive locomotion/oral movements in caged birds [35,36], with bar-mouthing in C57BL/6J mice [41], but not in ICR CD-1 mice [43], and with repetitive movement in clinical human patients [22,23]. Other studies have tied "stuckin-set" perseveration, the inappropriate maintenance of a plan or goal, to more complex ARBs like barbering in mice [1,41] and circumscribed interests in autistic humans [23].…”

Evidence for a relationship between cage stereotypies and behavioural disinhibition in laboratory rodents

“…Basal ganglia lesions in humans are similarly associated with stereotypy-like behaviour [1,39]. Stereotypy is also a common sign in disorders such as autism and schizophrenia [23,56,67]. In autism [67] and schizophrenia [23], the severity of stereotypy correlates with impairments on tasks designed to detect the unique signs of dorsal basal ganglia dysfunction.…”