A correlational study of stutterers' adaptation and voice initiation times

The purpose of this study was to determine the strength of the relationship, if any, between stutterers' amount of improvement in controlling phonation (voice initiation time) and their amount of improvement in stuttering during adaptation.Thirteen adult stutterers were required to participate in an adaptation task and a voice initiation time (VIT) task. The major finding was a weak, positive correlation between subjects' adaptation and their VIT difference scores. The correlation obtained, though weak, was interpreted to be informative; namely that while there is quite probably a laryngeal component in stuttering, it does not stand alone. It seems likely that the complexities of stuttering will not be fully understood until experiments include a number of potential or known dimensions of the disorder.     

Visual problem solving in the absence of lexical semantics: Evidence from dementia

A case of dissociation between visual and praxic skills and linguistic, referential, and semantic skills is described in a case of dementia. Testing revealed that her visual processing was intact and that she was capable of a wide range of visually based tasks. These included copying geometric figures and block designs; matching items on the basis of number, color, or relative size, matching upper and lower case letters, sequencing numerals, orienting pictures, coins, and letters appropriately, and solving problems based on the identification of geometric patterns or on the identification of logical sequences based on pattern alternation, number, and size increases. In contrast, she was completely incapable of matching pictures on the basis of their semantic or referential meaning; similarly she had lost all comprehension of language. It was argued that this case demonstrates the capacities of a visual system cut off from all symbolic and semantic processes. When examined with other case studies this case provides information about the nature of and interaction between modality-specific perceptual processing and semantic processing, and information about the various cognitive factors involved in visual gnosis. The CT scan indicated frontal atrophy and marked anterior temporal atrophy, a pattern that is consistent with Pick's disease. The case was discussed in terms of the correlation between the pattern of observed strengths and deficits and the neurological pattern of atrophy.     

Probability learning and coping in dysphoria and obsessive-compulsive tendencies

The processing of stress-relevant categorical events and their contributions to subsequent probability judgments were examined among subjects who were psychometrically categorized as dysphoric, obsessive-compulsive, or “control.” stress-relevant symptomatology of depression was considered to be characterized by a deficit of active counterstress coping activity and obsessive-compulsiveness by ritualistic efforts which have little or no direct effect on stress occurrence. Subjects were presented with a sequence of stressful (loud white noise) and benign (illumination of a green light) events in association with a series of discrete stimuli (alphabetic letters) in three conditions of counterstress activity. Results generally supported the predicted tendency to learn probability information primarily in conditions which reflected the subjects' characteristic ways of responding to stress. Obsessive-compulsives acquired the information primarily in a “ritualistic” context, controls in an active coping context, and dysphorics in both a coping deficit context and unexpectedly in an active coping context. The role of enhanced stressor predicability in maintaining typical stress response patterns of the three groups was discussed.     

Effects of eye movements on the recognition and localization of dichotic stimuli

Three experiments examined the effect of gaze shifts on overall performance and ear differences in dichotic listening. In the first two experiments, lights were switched on and off so as to induce rightward, leftward, or upward gaze during dichotic stimulation. The dichotic material consisted of musical passages in Experiment 1 and two kinds of verbal material in Experiment 2. Vertical eye movements enhanced the accuracy of identification of music but not verbal material. The lateral direction of eye movements affected subjects' ability to localize targets in Experiment 1: localization was more accurate in the direction toward which subjects were looking. In the third experiment it was found that optokinetic nystagmus (OKN) influenced the asymmetry of performance on a dichotic consonant-vowel (CV) test. The right-ear advantage was greatest when the OKN drum rotated from left to right and least when it rotated from right to left. The effect was due to corresponding variation in left-ear scores. Possible mechanisms through which shifts of gaze affect auditory identification and localization are proposed.