Logical and nonlogical classification systems: A look at the underlying complexity of overinclusion in schizophrenics
✍ Scribed by Judith E. Sims-Knight; Raymond A. Knight
- Book ID
- 102674988
- Publisher
- John Wiley and Sons
- Year
- 1978
- Tongue
- English
- Weight
- 792 KB
- Volume
- 34
- Category
- Article
- ISSN
- 0021-9762
No coin nor oath required. For personal study only.
✦ Synopsis
Although overinclusion is hypothesized to be a thought disorder, it has been found to be related to positive variables-good rognosis, good premorbidity, and good picture recognition. We hypothesizei that some overinclusive responses involved an alternative classification system to conventional logical classification and that these alternative systems might facilitate pictuie recognition performance. Twent seven male schizophrenics were given the Object Classification Test, the Ogject Sort,ing Test, and a picture recognition task. In addition to standard measuies of overinclusion, res nses were categorized according to (a) extent to which objects were classifieEonsistently and exhaustively by common attributes. and (b) adequacy of the common attributes employed. Four separable lunds of responses were found: nonlogical classification, reclassification (ability to change the basis of sorting), classification that engages the logical task, but does so imperfectly (logical ap roximates), and overextensiveness (making an overly general, nonexcfusive category). Only the first two weie related positively to recognition peiformance. These resuits suggest that overinclusion measures several different response tendencies and that some of them, but not all, help schizophrenics to compensate for their disorder. Cameron (1947 ; believed that aberrations in conceptualization, which he called overinclusive thinking, were essential to schizophrenic thought disorder. He hypothesized that schizophrenics' concepts were (a) overextensive; (b) broad, vague, and imprecise; and (c) interpenetrated with personal, imaginal, and environmental themes. Unfortunately, subesquent research often has found such inconsistent results that Payne (1971) was forced t o conclude that overinclusion might not be a useful concept.
Nevertheless, certain intriguing findings continue to accrue. First, several studies have found that overinclusion was related to good prognosis and good pre-