Absolute and relative performance of schizophrenics under competition.

Tested 40 chronic schizophrenics and 40 psychiatric attendants on a word-naming task under 1 of 2 testing conditions (alone and paired competitive, or alone and paired noncompetitive) and under 1 of 2 testing orders (alone-to-paired or paired-to-alone). Schizophrenics performed better under paired competitive trials than paired noncompetitive trials. When absolute performance level was considered, there were no differences between s groups in their relative response to competition. Paired-to-alone testing order reduced performance level for most groups independent of the competitive conditions. Results are interpreted in terms of motivation arousal. Schizophrenics respond as well as normals to competitive stimuli under the appropriate conditions. Competitive effects seem to be no different than a host of other activators which reduce the "psychological deficit" of schizophrenics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Self-editing deficits in schizophrenia: A word-association analogue.

Made contrasting predictions to differentiate a 1- from a 2-stage model of word-association performance in schizophrenia. 24 schizophrenics and 24 normals provided word associations in response to (a) "free" vs. "idiosyncratic" instructions, and (b) stimulus words that typically elicit either a strong dominant or several weak associations. Results confirm the 2-stage model: under idiosyncratic instructions, schizophrenics produced more common associations than normals. Findings were consistent with 2 assumptions pertinent to the 2-stage model: schizophrenics (a) sample from an underlying repertoire of nondeviant associations; and (b) are deficient in the ability to edit out sampled but situationally inappropriate associations, whether common or unusual. (18 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Backward-masking performance in chronic and nonchronic schizophrenics, affectively disturbed patients, and normal control subjects.

There is ample evidence that schizophrenics exhibit a backward masking deficit. To what extent other psychotic patients are susceptible to visual masking is still an open question. Likewise, differences between subgroups of schizophrenics have to be further explored. In the present study, a computerized backward masking task was applied to 30 schizophrenics, 18 affectives, and 20 normals. Results confirmed previous findings of a performance deficit in the schizophrenics. However, affectively disturbed patients performed even poorer than the schizophrenics. The most outstanding finding when the group of schizophrenics was split into different subgroups was the significant differences that appeared between chronic and nonchronic patients. The latter group (n?=?8) performed as well as the normals, while the chronic schizophrenics (n?=?22) showed evidence of a performance deficit comparable to the affectives. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Studies in efficiency: Verbal conditioning as a function of degree of task centering. A replication.

The present study is an approximate replication of an experiment by Letchworth and Wishner (1962). Its substantive purpose was to test the effects on verbal conditioning of self- and other centered (SC and OC) instructions in interaction with 2 types of task orienting instructions. From the concept of efficiency it was predicted that there would be a significant interaction of the following form: SC Ss would have a relatively higher rate of conditioning than OC Ss under relaxed instructions, while the reverse would be true under problem instructions. Procedural changes from the previous study were incorporated in order to increase experimental control. A significant interaction supported the experimental hypothesis and duplicated the results of the previous study. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Studies in efficiency: Semantic generalization in schizophrenia.

This study examined the hypothesis that schizophrenics would generalize a conditioned GSR response relatively more to the homonym of a CS and relatively less to the synonym than normals. The specific prediction was that the difference in the magnitude of response to synonyms and homonyms (RS - RH) would be greater for normals than for schizophrenics. The Ss were 16 normals and 16 chronic schizophrenics. The synonyms elicited a larger response than the homonyms with the majority of normal Ss. The opposite results were obtained with the schizophrenics. An analysis of variance clearly supported the hypothesized interaction between the "normal-schizophrenic" variable and generalization to synonyms and homonyms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Perceptual contact with reality in schizophrenia.

"It was hypothesized that under experimental conditions involving minimal distance cues, schizophrenics in poor contact would manifest less size constancy than either schizophrenics in good contact or normals. Three groups of subjects, schizophrenics in good contact with reality, schizophrenics in poor contact, and normals, were tested in a size-constancy experiment under three different distance cue conditions, maximal, minimal, and no cue. The results of the investigation supported the hypothesis. This was interpreted as suggesting that the schizophrenic's break with reality involves not only more complex psychological functions, but basic perceptual processes as well." 20 references. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The interpersonal distance of process and reactive schizophrenics.

Attempted to determine whether process and reactive schizophrenic males would use their interpersonal space differently from each other and from a normal control group. Data from 4 measures of interpersonal distance do not indicate that process schizophrenics were more interpersonally distant than reactive schizophrenics or normals, but suggest that the hypothesized differences in social adequacy between process and reactive patients and normals were not reflected in their use of interpersonal distance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Failure and the subsequent performance of schizophrenics.

"The present study investigated the questions of whether deficit would obtain for schizophrenics on a timed task of nonsocial content and, if so, whether the deficit would increase or decrease over trials under a condition of nonreinforcement and, finally, differentially affect the subsequent performance of schizophrenics and normals… . The results indicated that both schizophrenics and normals responded with enhanced performance to the negative conditions, but that only the schizophrenics demonstrated enhanced performance under the positive condition." 15 references. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Associative interference and premorbid adjustment in schizophrenia.

The effects of associative interference on the verbal learning performance of 60 male process and reactive schizophrenics and 30 normals were studied using a mixed list with high and moderate interlist interference and new learning conditions. Schizophrenics made more errors than normals in the interference conditions but not in the new learning. Reactive schizophrenics made as many errors as the process group with high interference but significantly fewer under moderate interference. Process schizophrenics gave significantly more List 1 intrusions in List 2 learning than reactives or normals. Results support predictions from the qualitative differences theory of cognitive deficit. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Psychophysiological reactions to films by chronic schizophrenics: II. Individual differences in resting levels and reactivity.

Resting skin-resistance, heart-rate, and reactivity data to 1 of 2 tension-arousing films were obtained from 2 normal comparison groups and a sample of drug-free chronic schizophrenics. The schizophrenics were subdivided into 3 subsamples on the basis of the number of deviant associations given to a word-association test. The resting skin-resistance data failed to discriminate between normals and schizophrenics; however, meaningful differences were found among the schizophrenic subsamples such that increasing thought disturbance was associated with increasing basal resistance levels. Basal heart-rate data did indicate faster heart rate for all schizophrenic subsamples compared with both normal groups. Reactivity data also indicated different results for the 2 indexes. Skin-resistance indexes failed to indicate any differences between schizophrenics and normals or among the schizophrenic samples. 1 heart-rate index suggested less reactivity for schizophrenics than for normals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Vocabulary performance of short-term and long-term schizophrenics.

"The following three measures of vocabulary performance varying in sensitivity were obtained from groups of short-term schizophrenics, long-term schizophrenics, and normals equated for art and education: gesticulation (nonverbal), conventional vocabulary achievement, and level of verbal communication. No differences were found between the short-term schizophrenics and the normals of any of the measures. The long-term schizophrenics were significantly lower than normals and short-term schizophrenics on all of the measures. The decrement on gesticulation for the long-term schizophrenics was significantly less than that for the other measures." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Proprioception in schizophrenics and normals: Effects of stimulus intensity and interstimulus interval.

Obtained weight discrimination thresholds for 18 schizophrenics and 18 normals at various levels of weight intensity and presentation interval. The discrimination performances of all Ss were evaluated in terms of Weber ratio scores and the number of correct discriminations for each test condition. Differential effects attributable to diagnosis were found, with schizophrenics performing with less accuracy than normals at the lowest level of weight intensity. The different presentation intervals did not yield significant differences in discrimination. It is concluded that there is a proprioceptive deficit in schizophrenia which is due to inadequate sensory input and not to insufficient proprioceptive memory. Signal-detection theory is acknowledged as providing a possible alternative explanation of the results. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hypnotic susceptibility of schizophrenic patients.

Clinical lore and much of the previous literature has maintained that schizophrenics are far less susceptible to hypnosis than are normals. A few studies have reported success with hypnotizing schizophrenics, but have lacked a methodology which would permit comparison with normal Ss to be made. In this study, 26 Ss with a hospital diagnosis of schizophrenia were given the Stanford Hypnotic Susceptibility Scale—a verbatim induction technique and rating scale for which data on a normal, standardization group is available. The Ss gave results much like the normal group. Reasons for the difference between this and previous findings are discussed, including the hypothesis that previous workers found schizophrenics to be different in hypnotizability from normals because they treated them differently than they would normals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Studies in efficiency: Muscle-action patterns in reaction time as related to GSR conditioning.

A significant interaction between degree of efficiency in reaction time and in meeting task requirements in the GSR conditioning situation was found, such that efficient Ss tended to take longer to reach criterion under instructions to relax, while there was no difference between the groups when the requirement was to solve a problem. Under the relax instructions the correlation of right- to left-arm tension with trials to successive CRs was .60; under problem instructions it was -.04. Taken together with the previous studies, these results are interpreted as support for the method of analysis implied by the concept of efficiency. They prepare the way for further tests of the hypothesis that efficiency will be related to degrees of psychopathology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cutaneous sensitivity in schizophrenics and normals under two levels of proprioceptive arousal.

Compared the cutaneous sensitivity of 20 normals and 20 schizophrenics (mean ages-30.5 and 30.2 yrs, respectively) under conditions of relaxation and of muscle tension. Schizophrenics were less sensitive than normals to cutaneous cues. Schizophrenic-normal differences were maximized at the most peripheral, least cortically represented of the physical locations sampled. No significant effects on cutaneous sensitivity were produced by muscle tension as opposed to relaxation. (28 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Choice of association by schizophrenics as a function of probability.

Used a complex probability-learning paradigm in a study with 15 inpatient schizophrenics (mean age = 28 yr.) and 44 normal college students. An 80:20 and 60:40 probability ratio was used to establish 2 response hierarchies simultaneously. Only the 60:40 ratio discriminated the schizophrenics from normals: schizophrenics chose the primary association significantly more often. There are at least 2 interpretations possible: (a) schizophrenics differ from normals on associative chains lacking a strong primary association and respond by overemphasizing small differences, or (b) schizophrenics are less sensitive to exact probability cues and adopt arbitrary response ratios that recognize that 1 association is more probable than the other. Results support L. Chapman's conception of schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The specificity of response interference to schizophrenia.

Recent research has emphasized that the greater-than-normal response interference in schizophrenics is a specific characteristic of schizophrenia. Since arousal is an important variable in response interference and since schizophrenics show patterns of overarousal, it is suggested that arousal would be important to control if behavioral differences between schizophrenics and controls are to be attributed specifically to schizophrenics' special problems of response interference. These ideas were tested by replicating a study by W. E. Broen and L. H. Storms (see record 1964-07261-001) using an overaroused control group of 15 nonpsychotic psychiatric inpatients, 15 nonparanoid schizophrenics, and 15 normals in a visual discrimination task. Data show that both the overaroused controls and schizophrenics, while not differing from each other, showed greater decrement of correct responding with increased arousal than the normal controls. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Time estimation in process-reactive schizophrenia.

Process and reactive schizophrenics, and reactive schizophrenics and normals were compared as to their responses on a perceptual time-estimation task. Null hypotheses being tested were that groups would not differ in variability or accuracy of response. Schizophrenic (45) and normal (15) subjects were selected from the male patient population and hospital employees, respectively, of a Veteran's Administration hospital. Schizophrenics selected for the study were classified by means of the Abbreviated Becker Elgin Scale. Subjects were individually administered a time-estimation task consisting of seven stimulus cards which were tachistoscopically presented, with exposure speeds at 10, 20, and 30 seconds for each card. Judgments of exposure times were converted into scores based upon ratios of estimated time to actual time. Scores (three) for each card were totaled. Groups were then compared on each of the stimulus cards by means of two-tailed t tests. In accuracy of estimation, process schizophrenics demonstrated significantly less accuracy than did reactives on four of the seven cards; no differences were shown between reactives and normals in accuracy of estimation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Size constancy in mental retardates and normals: A signal-detectability analysis.

Investigated size constancy differences among 11 institutionalized retardates, 6 noninstitutionalized retardates, 12 institutionalized normals (prison inmates), and 20 noninstitutionalized normals (college students) by psychometric function, signal detectability, and uncertainty analyses. Both retarded groups were perceptually deficient in making size judgments. This impairment paralleled that found between nonparanoid schizophrenics and normals by R. Price and C. Eriksen (see pa, vol. 40:9050). In addition, institutionalized retardates were less consistent in use of decisional rules than noninstitutionalized retardates. (PsycINFO Database Record (c) 2010 APA, all rights reserved)