A STUDY OF DIVERGENT THINKING IN APHASICS AND RIGHT BRAIN-DAMAGED NON-APHASIC SUBJECTS

One of the best known theoretical models which has been formulated to explain human cognition is the structure-of-intellect paradigm advanced by Guilford (1967). Although Guilford's paradigm consists of 120 factors, it is his concepts of divergent and convergent thinking abilities which have received the most attention (Akhurst, 1970).; Divergent behavior involves the generation of logical alternatives from given information; emphasis is upon variety, quality, and relevance of output from the same source (Guilford, 1967). It is concerned with "the generation of logical possibilities, with the ready flow of ideas, and with the readiness to change the direction of one's responses" (Chapey, et al 1976). Divergent behavior involves fluency, or the production of a number of ideas, and flexibility, or the generation of a variety of ideas.; In opposition to divergent thinking is the concept of convergent thinking. Convergent thinking is in operation when the input information is sufficient to determine a unique answer.; Although Guilford's study of convergency and divergency involved "normal" adults and children, Chapey, et al (1976) extended these concepts to the area of adult aphasia. These authors have suggested that a divergent as well as a convergent component exists for the impairment seen in aphasia.; The purpose of this study was to compare divergent thinking abilities in four groups of subjects: Broca's aphasics, Wernicke's aphasics, right brain damaged subjects and normal control subjects. Each group consisted of 10 subjects for a total of forty. Each subject was required to meet specific criteria.; The stimulus battery was composed of six divergent tasks by J. P. Guilford. Included in the battery were two tests of symbolic content (First and Last Letters Test and the Rhymes Test), two tests of figural content (The Sketches Test and the Monograms Test), and two tests of semantic content (The Utility Test and the Object Naming Test). Prior to the presentation of the stimulus battery, the aphasic and right brain damaged subjects were administered a cursory comprehension screening test and a test for constructional apraxia. The Boston Diagnostic Aphasia Examination (BDAE) was used as a pretest for aphasic subjects. In addition, the auditory comprehension and naming sections of the BDAE were used in an analysis of the aphasic and right brain damaged subjects. Results of the study indicate: (1) a deficit in the performance of Broca's and Wernicke's aphasics when compared to normal subjects. (2) no significant difference in the performance of the Broca's and Wernicke's subjects. (3) no statistically significant quantitative differences in the aphasic and right brain-damaged subjects. There were, however, some qualitatitive differences observed in the performance of those subject. (4) no statistically significant differences in the right brain damaged and normal control subjects.; The results concur with the findings by Chapey, et al (1976) that aphasics are deficient in their divergent semantic production abilities. Aphasia is not only a convergent impairment (the ability to "recognize and reproduce previously learned semantic materials and to converge upon one correct semantic response", Chapey, 1976) but it is a divergent impairment as well (the ability to generate a variety of responses). To take Chapey's concepts even farther, aphasia involves not only an impairment in divergent semantic production but an impairment in divergent figural and divergent symbolic production as well. The results also support Aten and Faber's (1979) findings that fluent and non-fluent aphasics are deficient in their divergent figural production abilities.