title: The use of a backward masking paradigm to assess information-processing deficits among schizotypics. A re-evaluation of Steronko and Woods.
abstract: In 1978, Steronko and Woods (J. Abnorm. Psychol., 87: 481-490, 1978) failed to find significant differences in early visual information processing between "schizotypic" and "psychiatric control" college students, as identified by the MMPI; yet these authors concluded that schizotypics suffer from information-processing deficits. The present study was designed to extend and clarify these findings by modifying the methods and procedures used by these researchers. A visual backward masking task was employed to study the information processing of individuals whose MMPI-168 profiles indicated schizophrenic tendencies in the absence of an obvious thought disorder. These schizotypic individuals were identified by the MMPI 2-7-8 code type and were compared with three other groups, also identified by their MMPI profiles: an "inflation-free" control group, an "other-inflations" control group, and a group with an 8-9/9-8 MMPI code type. The 8-9/9-8 code type has been associated with psychotic features in adolescents and adults. Two dependent measures were evaluated: critical stimulus duration in a no-mask condition and mean target identification as a function of varying interstimulus intervals. The 2-7-8 group had significantly higher critical stimulus duration values than either the inflation-free group or the 8-9 groups. The 2-7-8 group and the 8-9 groups had fewer correct identifications of target stimuli than either the inflation-free group or the other-inflations group. These results suggest that both the 2-7-8 group and the 8-9 group may be more vulnerable to the effects of the masking stimulus.(ABSTRACT TRUNCATED AT 250 WORDS)
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D005556:Form Perception; D006801:Humans; D008950:MMPI; D008297:Male; D008568:Memory; D008570:Memory, Short-Term; D010364:Pattern Recognition, Visual; D010470:Perceptual Masking; D011930:Reaction Time; D012559:Schizophrenia / Q000235:genetics; D012565:Schizophrenic Psychology; D012569:Schizotypal Personality Disorder / Q000235:genetics / Q000523:psychology*