Mnemonic organization in young nonpsychotic schizophrenics.

Describes 2 experiments with 18-27 yr old nonpsychotic schizophrenics (n = 32), nonschizophrenic psychiatric patients (n = 112), and nonhospitalized normals (n = 32). In Exp. I, Ss were given repeated free-recall trials of 20 "unrelated" words and of 20 categorized words. The schizophrenics' recall and mnemonic organization, as indexed by measures of subjective organization, categorical clustering, and hierarchical clustering schemes, were both inferior to those of the normals and, to some extent, to those of the nonschizophrenics. While the normals and nonschizophrenics tended to build up higher-order mnemonic units with trials, this trend was weak in the schizophrenics. In Exp. II, nonpsychotic schizophrenics and normals engaged in repeated recognition tasks of 40 words and 40 consonant-vowel-consonant trigrams. The recognition memory of the schizophrenics was the same as that of the normals, in spite of contextual variations of the study and test lists. Results are interpreted on the basis of the 2-process theory of recall as supporting the view that the basic deficit of schizophrenia in mnemonic processing is a difficulty in unitizing the material. (36 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Recognition versus recall in schizophrenia.

Twenty-four schizophrenic and 24 normal Ss, 8 in each group being overinclusive and 16 non-overinclusive, were presented with two 20-word lists, one for free recall and one for recognition. The recognition alternatives were rhymes, synonyms, and synonym-rhymes of the various target words. Schizophrenics were poorer than normals in recall but not in recognition, and the ratio of recall over recognition was significantly greater for schizophrenics than for normals. The results of an analysis of the recognition errors suggested that the recall deficit of schizophrenics may be due to an inability to organize information for retrieval. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The structure of word storage in the permanent memory of nonpsychotic schizophrenics.

Conducted 2 experiments to assess the storage structure of common English words in the memory of young nonpsychotic schizophrenics. 37 schizophrenic and 12 nonschizophrenic psychiatric patients and 36 normals were Ss in the 2 experiments. Ss in both experiments sorted words on the basis of the similarity of relatedness they perceived, but Ss in Exp II performed this task under time pressure. Assuming that the structure underlying these sortings reflects the storage structure of memory, a method of cluster analysis was applied to the data. The structural features extracted for all Ss were very similar to each other. A group difference was found in the S's sorting strategy, but its effect on the main findings was minimal. It is concluded that the storage structure of words in the memory of schizophrenics is probably intact. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Encoding processes and memory for categorically related words by schizophrenic patients.

Hypothesized that schizophrenics display a deficit in recall relative to recognition (as well as other memory deficits) because they encode the conceptual attributes of to-be-remembered items less frequently than normals. An experimental procedure consisting of 2 phases, incidental learning and long-term retention, was used to test 30 schizophrenics and 26 normal adults. During incidental learning, Ss were presented with 36 short word lists. After each, they recalled a single word that was detectable (i.e., encoded) on the basis of its conceptual category. Two variables were manipulated orthogonally: the probability that items were encoded conceptually and the number of times items were presented. Long-term retention of all items presented during incidental learning was tested in free-recall, category cued recall, and recognition tests, administered in that order. Results show an overriding similarity of schizophrenics to normals in patterns of response to the major variables, providing no support for the hypothesis. Data are consistent, however, with the hypothesis that schizophrenics encode items less elaborately than normals do. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Contextual effects on the short-term memory retrieval of schizophrenic young adults.

Two experiments were performed to determine if the dysfunction in mnemonic organization often found in schizophrenic free-recall performance is the result of an organizational deficit in short-term memory processing. In Exp I, which tested 16 schizophrenics, 16 nonschizophrenic psychiatric patients, and 16 nonpatient controls, categorical cues (letters and digits) were introduced into a Sternberg item recognition task. Schizophrenics utilized the categorical cue to reduce their latencies for search and retrieval as well as did both normals and nonschizophrenic psychiatric patients. In Exp II, which used a Sternberg context-recall task and tested the same number and type of Ss (31 also served in Exp I), latencies for both forward and backward sequential retrieval were measured. Schizophrenics again performed as well as controls. Data also suggest that the retrieval strategies adopted by schizophrenics were comparable to those of controls in both experiments. It is concluded that schizophrenics' short-term memory processes for categorical and sequential materials are adequate and therefore are not responsible for the organizational dysfunction in their free-recall performance. (38 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Intrusion of associative responses into schizophrenic conceptual performance.

One normal and one schizophrenic group, each consisting of 32 adult males, were required to sort cards bearing the name of a common object with 3 guide-card words—one sharing a concept with the sorting-card word, one with an associate connection to it, and one which was irrelevant. The schizophrenics were expected to make more associative errors than the normals. The results indicated that both difficulty in forming concepts and susceptibility to associative distraction are in part responsible for the fact that schizophrenics show more associative intrusions than do normals. 23 references. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A prediction of patterns of schizophrenic error resulting from semantic generalization.

Conducted a study with 2 groups of 26 male schizophrenics and normal psychiatric aides (mean age = 45 yr) to test predictions derived from a theory of disordered thought by L. J. Chapman, J. P. Chapman, and G. A. Miller (see PA, Vol. 39:10059) concerning the conditions under which schizophrenic Ss exhibit excessive generalization errors. The theory assumes that both the schizophrenic and normal are biased toward responding to words in terms of the words' strongest aspects of meaning, but that schizophrenics are more strongly biased toward this than are normals. Ss were instructed to indicate by pressing buttons marked "yes" and "no" whether or not test words presented in serial fashion on a memory drum had appeared on a previous training list. "Yes" responses to test words not appearing on a previous training list were the measures of generalization errors. The predictions were supported by the finding that schizophrenics made significantly more errors to words on the test list that shared strong meaning responses (p     

Distractibility in the conceptual performance of schizophrenics.

This study explores the role of interfering factors in the conceptual performance of schizophrenics. 40 schizophrenic patients at the Downey Hospital and 25 normals were used as Ss. They were required to sort cards containing 4 figures with 3 four-figured standard cards. One figure on each standard card was arbitrarily designated as correct for sorting. More of the schizophrenics than the normals used the incorrect "distracter" as a basis for sorting, even when conceptual sorting was required. The results support the hypothesis that schizophrenics fail conceptual tests because response to distracters prevents the demonstration of his concept-forming ability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of weight intensity on discrimination thresholds of normals and schizophrenics.

20 male chronic schizophrenics, 12 chronic disturbed schizophrenics, and 20 normal controls were tested for upper difference limens from both a 40-gm (light) and 400-gm (heavy) standard weight. Weight discrimination thresholds were found to be significantly elevated as a function of severity of pathology in the schizophrenic groups and also at the lighter weight intensity. Both groups of schizophrenics showed significantly greater improvement than normals with the heavy weights. The less disturbed chronic schizophrenics were not significantly different from normals at the heavy intensity. The results support the hypothesis of a schizophrenic deficit in proprioceptive acuity and suggest that this deficit is the result of insufficient proprioceptive feedback. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Abstract thinking deficit and autism in process and reactive schizophrenics.

Evaluated the influence of inability to abstract and autism on the proverbs interpretations of process and reactive schizophrenics. 48 reactive schizophrenics, 48 process schizophrenics, and 24 normals were scored for abstract level and autism on D. R. Gorham's (see record 1957-01037-001) proverbs test. Compared to normals, both schizophrenic groups were abnormal on each measure, both before and after the groups were matched for vocabulary. However, process schizophrenics were more deficient on abstract level than reactives. There was no significant difference between the mean autism scores of the two schizophrenic groups until the effects of abstract level were removed. Then it was seen that autism was more prominent among reactives than process Ss. Studied independently of one another, loss of abstract ability characterized process schizophrenics, while autism was more typical of reactives. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Proprioception and schizophrenia: a replication study with nonschizophrenic patient controls

In 3 experiments, weight discrimination, arm flexion discrimination, and a test of kinesthetic figural aftereffects were used to evaluate the proprioceptive functioning of 40 schizophrenic patients, 30 nonschizophrenic (psychotic and nonpsychotic) patients, and 10 normals. The additional variables of premorbid functioning and paranoia were also examined. Previous findings of a subtle proprioceptive deficit for schizophrenics in comparison with normals were replicated for nonparanoid schizophrenics of a weight-discrimination procedure and poor premorbid schizophrenics on an arm-flexion task. The kinesthetic-figural-aftereffects schizophrenic deficit previously reported by the author and E. Ebner (see record 1974-23243-001) was not replicated. Deficits in proprioception also were found for all nonschizophrenic patient groups on the weight-discrimination procedure and for poor premorbid nonschizophrenic psychotics and neurotics on the arm-flexion task. It is concluded that a deficit in proprioception is not unique to schizophrenia but appears to be related to chronicity and severity of pathology in both schizophrenic and nonschizophrenic hospitalized patients. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Creating false memories: Remembering words not presented in lists.

Two experiments (modeled after J. Deese's 1959 study) revealed remarkable levels of false recall and false recognition in a list learning paradigm. In Exp 1, Ss studied lists of 12 words (e.g., bed, rest, awake); each list was composed of associates of 1 nonpresented word (e.g., sleep). On immediate free recall tests, the nonpresented associates were recalled 40% of the time and were later recognized with high confidence. In Exp 2, a false recall rate of 55% was obtained with an expanded set of lists, and on a later recognition test, Ss produced false alarms to these items at a rate comparable to the hit rate. The act of recall enhanced later remembering of both studied and nonstudied material. The results reveal a powerful illusion of memory: People remember events that never happened. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Phonemic storage of concrete and abstract words with auditory presentation.

Conducted 2 experiments in which Ss' recognition memory for aurally presented concrete and abstract nouns was tested. In Exp I, 56 undergraduates heard study and test lists of 20 concrete and abstract nouns. The test list contained the same 20 nouns plus 20 new nouns which rhymed or did not rhyme with the study stimuli. In Exp II, 56 new undergraduates heard the same lists as in Exp I, but also heard lists in which concrete distractors rhymed with abstract study items and vice versa. Results show that false recognition depends upon the phonemic similarity of distractors to study words, and that the effect is independent of the concreteness of the words or whether the distractor matches the study word in concreteness. While the results may be inconsistent with aspects of the dual process theory of verbal coding, they may indicate that learners use phonemic attributes for recognition when imaginal attributes are insufficient. The appearance of an overall effect of concreteness on false alarms indicates that auditory presentation can produce imagery codes. (French summary) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Schizophrenic short-term memory: The role of organization at input.

Investigated schizophrenics' ability to utilize input organization and auditory cues for recall. 32 7-letter lists, varying in degree of organization, were presented to 24 schizophrenic and 24 normal Ss for forced-order recall. 1/2 of the lists were vocalized aloud, the remainder articulated silently. Normals gave significantly better recall than schizophrenics, and voicing facilitated recall in both groups. Schizophrenics had greater difficulty in recalling items in the last serial positions than did normals. Schizophrenics' omissions increased monotonically with serial position, while the omissions of normals followed the serial position curve. Findings suggest that schizophrenics do utilize the cues of input organization and vocalization for recall, but the process of responding seems to engender excessive output interference which makes retrieval of late input items difficult. (35 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Interference effects in schizophrenic short-term memory.

Presented 35 lists of 7 digits to 24 16-41 yr old schizophrenic patients and 24 16-39 yr old matched normal controls. Items in the different serial positions were probed randomly in a series of 7 recall trials for each list. Input interference resulting from interpolation of items between presentation and recall of the probed item was the same for both groups. Output interference resulting from interpolation of responses between presentation and recall was greater for schizophrenics than for normals. Significant differences in error patterns were also found. It is concluded that output interference is a major causative factor in the schizophrenic recall deficit. (34 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)     

Abstract thinking and social behavior in schizophrenia.

20 normal and 24 schizophrenic Ss were presented a series of cards, each bearing a stimulus word and 2 response words variously related in meaning to the stimulus. The Ss were asked to select the response word which they felt to be "closer in meaning" to the stimulus word. The results confirmed, at the .01 level, the hypotheses that (a) normals will exceed schizophrenics in the ability to select, as most similar in meaning to a given word, that word which is related to it in an essential abstract way; and (b) within a schizophrenic group, the above ability will be positively correlated with adequacy of everyday social interaction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Category-order effects in memory span.

When Ss are required to recall lists containing both words and digits, memory span is higher when the digits precede the words than when the words precede the digits. In Exp 1, both forward and backward recall were tested; it was demonstrated that this category-order effect reflects the input position, and not the output position, of the items. Exp 2 revealed that this effect was not eliminated by a filled retention interval. Exp 3 showed that the effect was eliminated when lists were presented at a fast presentation rate. In Exp 4, the effect was eliminated when Ss engaged in articulatory suppression. A 5th experiment extended the findings of Exp 4 to the case in which lists are composed of semantically related or unrelated words. These results suggest that category-order effects reflect mnemonic activity that Ss engage in during list presentation and do not arise from structural characteristics of the memory system. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Shift in judgment of weights as a function of anchoring stimuli and instructions in early schizophrenics and normals.

"A weight judgment task was administered to 16 schizophrenic patients and 16 normals for 2 sessions. The two groups did not differ from each other in ability to discriminate between the weight stimuli, but the schizophrenics shifted significantly more than the normals in the heavy anchor condition, thus providing evidence for the theory that schizophrenics are more prone to react to concrete than to abstract stimuli, as well as for the theory that schizophrenics are less able to maintain constancy in weight judgment than normals." 18 references. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attention in schizophrenia: An analysis of selectivity in the functional visual field.

Presents a visual–spatial approach to the study of attention dysfunction. The hypotheses of broadened and narrowed attention were tested by comparing peripheral visual discrimination of 10 acute schizophrenic and 11 chronic schizophrenic inpatients and 16 normal Ss (hospital staff) within 2 regions of the functional visual field. Pairs of visual stimuli were presented at 4 display angles. Measures of response accuracy, response latency, and latency of eye movement of peripheral stimuli were obtained. Results indicate that acute schizophrenics generally discriminated peripheral signals more accurately than chronic schizophrenics or normals. Normals discriminated signals more accurately than chronic schizophrenics. Results suggest the differential use of selective strategies. Limitations in the use of peripheral information among chronic schizophrenics implies a reduction in the amount of information transmitted in a selective act and a reduction in the economy of selective activities. In contrast to normals, acute schizophrenics utilized more efficient selective strategies over a greater spatial area, implying greater transmission of information within discrete selective acts. Results also indicate that schizophrenics initiated eye movements earlier than normals and that response latency was greater for acute schizophrenics than for normals. Results are interpreted as providing partial support for P. H. Venable's (1964) theory of input dysfunction. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)