The Spontaneous Speech of Aphasic and Normal Adults in Response to Individual and Combined Stimulus Features.
Ronald Champoux · Deep Blue (University of Michigan) · 1981
This study attempted to determine (1)if manipulating the stimulus features, movement, sound, and color in videotaped presentation of scenes significantly affected the oral responses of aphasics or normal subjects as measured by each of four verbal dimensions--Promptness, Accuracy, Completeness, and Efficiency-- and (2)if there were significant differences between the responses of the aphasics and normals on each of the four verbal dimensions. The results of the study showed that the experimental conditions had no significant (p > .05) effects on the responses of the aphasics as measured by each of the dependent variables but had significant (p < .05) effects on the responses of normals on each of the dependent variables. The condition, movement, appeared to account for the greater number of post-hoc comparisons among the conditions for normals. There were significant (p < .05) scene effects on both asphasic and normal responses. Of the thirty-four post-hoc comparisons, three scenes, Hammering, Hot Combing, and Shaving, accounted for seventy-four percent of the significant (p < .05) comparisons. In addition, the aphasic subjects scored significantly (p < .05) lower than the normal subjects on each of the dependent variables. The lack of condition effects on the aphasic responses may suggest that manipulating features of two-dimensional stimuli did not help the aphasics of this study to evoke better or more oral responses. However, due to scene effects and the fact that severity of aphasia was not controlled, the results may reflect an interaction beween conditions and scenes or a ceiling effect reached by a number of the aphasics in the group who might be more severe than the others. The condition effects on the normals, especially those in which movement occurred, suggests that the normal subjects responded better when scenes were dynamic and not static. The results of this study support the results of other studies in which features of stimuli were manipulated in a naming task. Until differentiation by type and severity of aphasia is studied, and , until three dimensional scenes are studied, this suggests that, at present, a profile of an aphasic's language ability may just as well be obtained by responses to black and white line drawings of objects or scenes as looking at the actual objects or scenes. The results of the study do not agree with suggestions in the literature that action imagery may facilitate retrieval processes in aphasics. Indeed, there is a large body of literature indicating that linguistic cueing is more beneficial than nonlinguistic cueing in aiding these retrieval processes. The negative results of the present study and others employing perceptual features as cueing devices together with the positive results of studies employing linguistic features suggest that aphasia is first and foremost a linguistic problem and may be aided primarily by linguistic cues. (However, future research is necessary to investigate the effects of three dimensional cues on aphasic responses and whether types of aphasics are affected differently.) One feature of this study was the design of a multi-categorical scale employing the response parameters of Accuracy, Completeness, Promptness, and Efficiency. Although scoring reliability was not as high as would have been welcomed, the procedure shows clinical and research potential.