Defects of immediate memory related to the cerebral blood flow distribution

Different forms of memory defects were studied in 16 patients with organic dementia. The test performance was related to the regional cerebral blood flow (rCBF) in the left (dominant) hemisphere. Verbal memory (Paired Associates) correlated to the blood flow in temporal and parietal regions. Spatial recognition (Memory for Objects, Memory for Geometrical Design) correlated to the temporal and lower frontal regions. One spatial memory test (Visual Retention test) correlated to the temporal region only. Another spatial memory test (Memory for Design) did not show correlations to any regions of the dominant hemisphere. Finally it was found that the hemisphere mean flow values did not correlate to performance. This emphasizes the main finding—the regional correlations. It is concluded that memory performance involves various extratemporal regions depending upon the specific quality of the memory task to be performed.     

Regional blood flow changes in the left cerebral hemisphere during word pair learning and recall

Regional cerebral blood flow measurements were made in the left hemisphere of 11 young healthy volunteers during learning and during recalling of word pair associates. Compared to the resting baseline, both tasks caused significant increases of average hemispheric flow, indicating an elevated neuronal activity level. Regionally both tasks were accompanied by considerable activation of parietal and occipital regions. The main difference between learning and recalling was that only the former task activated the prefrontal regions.     

Hemispheric emotional asymmetry in a dichotic listening task.

In a dichotic listening experiment white noise was played to one ear and either music or poetry to the other ear. Subjects rated the stimuli on each of three dimensions. The results showed that both music poetry were judged as more pleasant when heard at the left than the right ear. In addition the music, but not the poetry, was perceived as more soothing at the left ear. The findings are discussed in relation to other indications in the literature that left and right cerebral hemispheres differ in their emotional make-up.     

Academic achievement: An examination of Holland's congruency,consistency, and differentiation predictions

This investigation tested three predictions derived from Holland's (1973) theory of vocational development regarding academic achievement. Groups of 392 male and 424 female entering college freshmen were typed using the Strong-Campbell Interest Inventory and were categorized in terms of congruency, consistency, and differentiation. Freshmen with congruent college major choices or with definite majors but indefinite Holland orientations enjoyed greater academic success than students who specified incongruent choices or no definite major choice. Students with personality codes of high or low consistency outperformed students with moderately consistent codes. Freshmen males with differentiated personal orientations achieved higher grade point averages than males having nondifferentiated personality profiles. For females, differentiation was not significant. In all sex comparisons female trends paralleled male trends and females generally outperformed males. Implications for vocational development and counseling were discussed in the context of Holland's theory.     

Individual differences in field articulation as a factor in language comprehension

Previous research has suggested that performance differences associated with field independence/field articulation (FA) reflect differences in the efficiency of a limited capacity “working memory” (WM) system. An information-processing analysis of language comprehension suggests the involvement of WM. This experiment tested the hypothesis that performance differences in a language comprehension task could be predicted on the basis of level of FA and the mediating role of WM. Three levels of memory load were established by varying the logical structure of sets of semantically related sentences which subjects were required to integrate. In the low memory load condition, there was no difference between high and low FA subjects on a test of integration (inference) and specific memory (recognition). In the high memory load condition, there was a decline in performance for low FA subjects on both inference and recognition. Other aspects of the results suggested that the breakdown in information processing, for low FA subjects in the high memory load condition, occurred during or shortly after initial encoding of the sentences.     

Effects of stimulus ear presentation on the voice reaction time of adult stutterers and nonstutterers

The initial and optimum voice reaction times (VRT) to auditory stimuli presented separately to the left and right ears of ten adult stutterers and ten nonstutterers was investigated. Subjects initiated the neutral vowel sound /Λ/ in response to one hundred 4000 Hz tones of 2.5 sec in duration. The silent intervals between the tones varied randomly. The stimulus cues were divided into five equal response sets of 20 tones each with 10 tones in each set being presented to the right ear and 10 tones to the left ear alternating back and forth. No significant differences were reported between the VRTs for cues presented to the left or right ears for either group. However, the stutterers exhibited voice reaction times which were significantly longer and more variable than those of the nonstutterers. The between- group differences were observed for what appeared to be the “optimum” level of voice initiation for the experimental task. These results lend to the speculative hypothesis that the observed difficulty for adult stutterers to promptly and consistently initiate vocalization may in part be attributable to inherent rather than learned factors.     

Cerebral dominance in aphasia recovery.

This investigation studied the patterns of ear preference of a group of 25 aphasic adults through the administration of two verbal dichotic tests and retests over a 2-month interval of time. These dichotic tests were a Dichotic Digits Test (DDT) and a Dichotic Animal Names Test (DANT). Schuell's short test of aphasia was given twice over this interval to assess language recovery. Results indicated that as aphasics improve in language, cerebral dominance becomes more firmly established in the right cerebral hemisphere. The data in this study tend to support a dominance shift hypothesis in the recovery of language after aphasia.