Has an important test been overlooked? Closure flexibility in schizophrenia.
Deficits in visual processing are now recognized as a core feature of schizophrenia. In the 1940s, Louis Thurstone developed a series of tests designed to evaluate specific aspects of visual perceptual processing including the Closure Flexibility Test (CFT), which was designed to measure "the ability to hold a configuration in mind despite distraction." The present study evaluated patients' performance on this task and its relationship to other tests of neuropsychological function, particularly to a measure of sustained visual attention. Thirty-nine patients with schizophrenia or schizoaffective disorder and 40 controls participated. The CFT was administered both in its original form (10 min) and also in a briefer form (3 min) in which only a portion of stimuli were given. Patients showed highly significant large effect-size deficits on both the original (d=1.6) and brief (d=1.2) CFT. Between-group deficits in performance survived co-variation for IQ. In addition, the CFT score was significantly related to performance on the MATRICS measure of attention/vigilance, the Continuous Performance Test-Identical Pairs version (CPT-IP). This correlation remained significant even after controlling for non-specific intercorrelations among neurocognitive measures. Results confirm the severity of early visual processing deficits in schizophrenia. In addition, the CFT is a brief, easy to administer alphabet-independent, paper-and-pencil test with established psychometric properties that may be useful as an index of the sustained visual attention construct in schizophrenia.
Butler
Pamela D
PD
Schizophrenia Research Center, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, United States. butler@nki.rfmh.org
Schechter
Isaac
I
Revheim
Nadine
N
Silipo
Gail
G
Javitt
Daniel C
DC
D000328:Adult; D000704:Analysis of Variance; D001288:Attention / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010466:Perceptual Closure / Q000502:physiology*; D010468:Perceptual Disorders / Q000209:etiology*; D011930:Reaction Time / Q000502:physiology; D012559:Schizophrenia / Q000150:complications*; D012565:Schizophrenic Psychology; D013997:Time Factors