Stimulus generalization as a function of clinical anxiety and direction of generalization.

"This experiment studied stimulus generalization in psychiatric patients as a function of direction of generalization and clinical anxiety. It was found that direction of generalization along the height continuum did not significantly affect the gradient of stimulus generalization. Level of clinical anxiety, as measured by the Taylor Manifest Anxiety Scale, also did not significantly affect the gradient of stimulus generalization. The validity of the Taylor scale with psychiatric patients was discussed briefly." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Differences in gradients of stimulus generalization as a function of "Abstract" and "Concrete" attitude.

Goldstein's concept of the loss of abstract attitude in psychopathology, was related to stimulus generalization along a visual-spatial dimension, with an apparatus requiring a voluntary response. Measurement was made of the gradient of stimulus generalization (GSG) of 34 "abstract" Ss, and 34 "concrete" Ss. These Ss were selected on the basis of their performance on 2 abstraction tasks (i.e., the Weigl-Goldstein-Scheerer Color Form Sorting Test, and the Wechsler-Bellevue block design subtest). The hypothesis that "concrete" Ss would have a lower GSG than "abstract" Ss, was tested and supported. The prediction that any differences observed would be independent of diagnostic category, was also substantiated. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Relationship of manifest anxiety to stimulus generalization.

This study examined the relationship between anxiety and stimulus generalization in psychiatric patients. The results suggested that "there is no relationship between MAS [Manifest Anxiety Scale] and stimulus generalization in psychiatric Ss. Moreover, situational factors do not seem important in limiting the generality of such an interpretation. Since the relationships between anxiety and learning phenomena are generally well recognized, these negative results presumably reflect the inadequacy of the Taylor scale as a relevant index of anxiety levels in psychiatric subjects." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Ethnocentrism and stimulus generalization.

"This study is an attempt to demonstrate that ethnocentrism is related to an 'over-generalization process' as has been postulated by various authors. The performance of a group of student nurses on a stimulus-generalization task was correlated with their scores on the California E scale yielding a significant μ = .44. Some possible theoretical implications are discussed and mention is made of further research which is in progress." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Conditioning and generalization of GSR as a function of awareness.

"This study was essentially a replication of… (an) experiment on the unconscious conditioning of autonomic responses. When… (the previous) methods of data analysis were used, their results in general were confirmed." Limitations and critique of the previous methodology is offered, and its effect on the results obtained is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Ethnocentrism and stimulus generalization: A replication and further study.

Data were previously reported giving "support to the hypothesis that ethnocentrism represents an 'overgeneralization phenomena.' " In a study of 60 female student nurses, aged 18 through 22, who were given the MMPI, the CVS Intelligence Scale, and the California Ethnocentrism Scale as well as two stimulus generalization (SG) tasks, significant correlations were not found between E Scale scores and total error scores on each stimulus generalization task. Previous positive finding "must therefore probably be attributed to chance. While present results do not preclude the possibility that ethnocentrism is related to overgeneralization in thinking, the functions involved in performance on the tasks investigated do not appear to be on the same psychological continuum." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Stimulus generalization as a function of clinical anxiety.

"It was hypothesized that the state inferred from manifest clinical symptoms of anxiety would show functionally similar motivational properties to the state of anxiety defined in terms of an implicit response that has been conditioned to situations involving noxious stimulation. It was predicted that both types of anxiety would exhibit the energizing properties of a drive and therefore elevate response gradients of generalization… . The results showed that the groups designated as high in clinical anxiety showed significantly more generalization than the low-clinical anxiety groups under the strong-shock condition. No difference was found between the 2 levels of clinical anxiety for either the weak-shock or buzzer condition." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mediated stimulus generalization and words connoting mood.

90 words connoting mood were scaled for degree of elation or depression. 70 of the words were selected as the stimuli in a study of mediated stimulus generalization. For 2 groups of men and 2 groups of women the training stimuli were extremely elated words, and for 2 different groups of men and women, the training stimuli were extremely depressed words. In each of the 2 groups for both sexes, one group was reinforced for whispering and the other for shouting. After training all groups received a generalization series consisting of words varying in degree of elation or depression. Ss trained to shout elated and whisper depressed stimuli produced steeper mediated stimulus generalization gradients than Ss trained to whisper elated and shout depressed stimuli. The Shout-Depressed group produced partially inverted gradients. The results were consistent with an asymmetrical Matching Principle: with connotative stimuli there is a strong tendency to make an intense response to an intense stimulus and a moderate tendency to make a weak response to a weak stimulus. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effects of social and nonsocial censure on stimulus generalization in neurotics and schizophrenics.

36 schizophrenic and 36 neurotic depressive Ss were given a visual-spatial generalization task under either social or nonsocial (impersonal) censure conditions. The following hypotheses derived from previous investigations were tested: (1) schizophrenics would show higher gradients of generalization than neurotic depressives, and (2) generalization gradients would be higher under conditions of social as opposed to nonsocial censure, especially in schizophrenics. The data supported Hypothesis 1 but not Hypothesis 2. There was no evidence for differential responding between these 2 groups with respect to either stimulus generalization or response to censure. It was suggested that hypotheses concerning the schizophrenic's performance in these 2 situations have been biased and oversimplified by use of normal, rather than patient, control groups in previous investigations. (22 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Contextual modulation of stimulus generalization in rats.

One connectionist analysis of the acquired equivalence/distinctiveness of cues assumes that when similar compounds (e.g., AX and BX) are paired with the same outcome (e.g., food, +; or no food, ?), their components come to activate the same configural unit (ABX). When these compounds are paired with different outcomes, their components will come to address different units. Here, rats received appetitive training with eight compounds (e.g., AX+, BX+, CX?, DX?, AY+, BY?, CY?, DY+) that should generate the following configural units: ABX, CDX, ADY, and BCY. In Experiment 1, rats then received aversive conditioning to A, which should activate and revalue representations ABX and ADY. Subsequently, compounds that provided dual activation (i.e., BX and DY) of one of the revalued configural units (ABX and ADY) were shown to elicit greater fear than those compounds that provided a single source of activation to each unit (i.e., DX and BY). Experiment 2 confirmed and extended these findings. These results provide support for the connectionist analysis outlined above and are consistent with the application of this approach to the acquired equivalence/distinctiveness of cues. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Distortions in the gradient of stimulus generalization related to cortical brain damage and schizophrenia.

Measurement of the gradient of stimulus generalization (GSG) of 60 schizophrenics (S group), 60 medical control patients (C group), and 60 patients with cortical brain damage (O group), by means of an apparatus consisting of a panel of 11 lamps placed in an arc around the subject, showed: "(1) The GSG for both the C and S groups is considerably more elevated than that of the control group (O group). (2) The differences between the S and C groups, while in the main in the predicted direction, are not conclusive. (3) Damage to the cortex of the dominant hemisphere results in considerably more diminution of the elevation of the GSG than damage to the cortex of the non-dominant hemisphere. (4) The number of EST's received by patients in the S group was found to vary inversely with the degree of SG responsivity; but in view of the limitations of the data, no conclusions were drawn." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Stimulus generalization.

An elaboration and criticism of the immense literature (127 titles) covering the subject. The definition is: when a response, previously trained to be elicited, can also be elicited by test stimuli similar, though with a gradient physically determined. Of course, the response might then also be generalized. Stimulations mentioned are tactual space, light intensity, time, pitch in hearing, loudness, seen angles and other drawings, "drive" intensified by drugs, etc. Theories distinguish irradiation in the cortex and irradiation over neural pathways. Historically, neural science does not seem to be quite ripe for theorizing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Social competence and outcome in psychiatric disorder.

Relationship of premorbid social competence of patients necessitating hospitalization to length of hospitalization, frequency of hospitalization, and time between hospitalizations was studied. Case histories of 251 patients were analyzed. As with previous studies, a positive relationship between the variables was found. Those at the lower end of the social competence continuum had longer periods of hospitalization and greater likelihood of rehospitalization. Social competence was therefore seen to be related to prognosis. Results were discussed in terms of developmental approach to personality and, in particular, psychopathology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Differences in stimulus generalization among psychiatric patients as a function of anxiety level-ego strength, sex, and time of testing.

80 nonorganic psychiatric Ss dichotomized on both manifest anxiety-ego strength level and sex were given a visual spatial stimulus generalization (SG) task within 4 days after admission and 9-15 days later. 2 SG measures and 2 measures of response latency were recorded at each time. Results showed that SG was not related to race, age, education, or admission status. Only time of testing was significantly related to SG and response latency, with all groups showing less generalization and shorter latencies from the 1st to the 2nd time. The 4 experimental groups did not differ significantly on number of Ss responding at least once to each peripheral light, relative SG improvement, SG gradients, or latency gradients. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Exemplar and prototype models revisited: Response strategies, selective attention, and stimulus generalization.

J. D. Smith and colleagues (J. P. Minda & J. D. Smith, 2001; J. D. Smith & J. P. Minda, 1998, 2000; J. D. Smith, M. J. Murray, & J. P. Minda, 1997) presented evidence that they claimed challenged the predictions of exemplar models and that supported prototype models. In the authors' view, this evidence confounded the issue of the nature of the category representation with the type of response rule (probabilistic vs deterministic) that was used. Also, their designs did not test whether the prototype models correctly predicted generalization performance. The present work demonstrates that an exemplar model that includes a response-scaling mechanism provides a natural account of all of Smith et al's experimental results. Furthermore, the exemplar model predicts classification performance better than the prototype models when novel transfer stimuli are included in the experimental designs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The application of conditioning and learning techniques to the treatment of a psychiatric patient.

"The treatment is described of a psychiatric patient who, in the framework of an emotional disorder, presented a disabling somatic symptom in the form of an abnormal frequency of micturation, especially evident when she was in public places or engaged in her profession of dancing… . After the laboratory treatment, considerable improvement in the patient's general condition was evident in a non-stressful environment, but a graded re-education program was necessary before effective relief from the symptoms in normal life situations was achieved." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mediated generalization and the incubation effect as a function of manifest anxiety.

"Two groups of 45 Ss each were chosen on the basis of extreme scores on the MAS [Taylor Manifest Anxiety Scale]. A conditioned PGR was first established by repeated pairings of a critical word (CS) with a raucous buzzer. Tests of mediated generalization were made following training, using as generalization stimuli, words to which the CS was associated as determined by free associations of a standardization group. In order to investigate the incubation effect the Ss were divided following training into three subgroups differing in the length of the rest interval between conclusion of training and the institution of extinction trials (immediate extinction, 10-min. interval, and 24-hr. interval). The results indicated heightened responsivity towards words associated with the CS, thus indicating that mediated generalization had taken place. It was also found that extreme MAS scores were directly related to the magnitude of mediated generalization responsivity." Level of manifest anxiety was found to be directly related to conditioning responsivity as well as to resistance to extinction. 20 references. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Screening for posttraumatic stress disorder in a general psychiatric outpatient setting.

Posttraumatic stress disorder (PTSD) may affect survivors of a number of accidents and illnesses, in addition to violence victims and combat veterans. Prior research suggests that PTSD may be underdiagnosed when trauma is not the presenting problem. Thus, a PTSD screening scale might have utility in routine clinical settings. The authors evaluated the screening performance of the Posttraumatic Diagnostic Scale (PDS) in a general psychiatric setting. Results indicated that the PDS performed as well in this setting as it did in the original trauma-focused validation studies, independent of PTSD status as a primary, versus secondary, reason for presenting. A simple cutoff score was adequate for case identification. There were no gender effects, and the scale performed equally well among patients with, versus without, a depressive diagnosis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Stimulus generalization and schizophrenia.

Paranoid and nonparanoid schizophrenics, on and off drugs, were compared with medical inpatients for stimulus-generalization responsivity. The stimuli were lines differing in length, and the response alternatives differed in amplitude. There were no significant differences in gradients of stimulus generalization among the groups. This finding opposes Mednick's original anxiety-drive theory of schizophrenia, especially his assumption that schizophrenics overgeneralize. The finding does not oppose Mednick's amended theory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Recency effects as a window to generalization: Separating decisional and perceptual sequential effects in category learning.

Accounts of learning and generalization typically focus on factors related to lasting changes in representation (i.e., long-term memory). The authors present evidence that shorter term effects also play a critical role in determining performance and that these recency effects can be subdivided into perceptual and decisional components. Experimental results based on a probabilistic category structure show that the previous stimulus exerts a contrastive effect on the current percept (perceptual recency) and that responses are biased toward or away from the previous feedback, depending on the similarity between successive stimuli (decisional recency). A method for assessing these recency effects is presented that clarifies open questions regarding stimulus generalization and perceptual contrast effects in categorization and in other domains. (PsycINFO Database Record (c) 2010 APA, all rights reserved)