Visuospatial Dysfunction in Patients With the Right Vestibular Neuritis / 대한평형의학회지

Acute vestibular neuritis (VN) is characterized by acute/subacute vertigo with spontaneous nystagmus and unilateral loss of semicircular canal function. Vestibular system in human is represented in the brain bilaterally with functional asymmetries of the right hemispheric dominance in the right handers. Spatial working memory entails the ability to keep spatial information active in working memory over a short period of time which is also known as the right hemispheric dominance. Three patients (patient 1, 32-year-old female; patient 2, 18-year-old male; patient 3, 63-year-old male) suffered from acute onset of severe vertigo, nausea and vomiting. Patients 1 and 2's examination revealed VN on the right side showing spontaneous left beating nystagmus and impaired vestibular ocular reflex on the right side in video head-impulse and caloric tests. Patient 3's finding was fit for VN on the left side. We also evaluated visuospatial memory function with the block design test in these 3 VN patients which discovered lower scores in patients 1 and 2 and the average level in patient 3 compare to those of healthy controls. Follow-up block design test after resolved symptoms showed within normal range in both patients. Our cases suggest that the patients with unilateral peripheral vestibulopathy may have an asymmetrical effect on the higher vestibular cognitive function. The right VN can be associated with transient visuospatial memory dysfunction. These findings add the evidence of significant right hemispheric dominance for vestibular and visuospatial structures in the right-handed subjects, and of predominant dysfunction in the hemisphere ipsilateral to the peripheral lesion side.

Reproducibility of Hemispheric Language Dominance by Noun, Verb, Adjective and Adverb Generation Paradigms in Functional Magnetic Resonance Imaging of Normal Volunteers

PURPOSE: We investigated the reproducibility of language lateralization by 4 different word generation paradigms or the rest contents in each paradigm using functional magnetic resonance imaging in normal volunteers. MATERIALS AND METHODS: Nine normal volunteers with left-handedness (mean age: 25 yrs) were examined on a 1.5T MR unit using a single-shot gradient echo epibold sequence. Four different word generation paradigms of noun, verb, adjective and adverb were used in each normal volunteer for investigating language system. In each paradigm, two different rest contents consisted of only seeing the "+" symbol or reading the meaningless letters. Each task consisted of 96 phases including 3 activations and 6 rests of 2 different contents. Two activation maps in one task were obtained under two different rest contents using the correlation method. We evaluated the detection rates of Broca and Wernicke areas and the differences of language lateralization among four different word generation paradigms, or between the rest contents. RESULTS: The detection rates of Broca and Wernicke areas were over 67% in 4 different language paradigms and there was no significant difference of them among language paradigms, or between two different rest contents. Language dominances, in all 4 different language paradigms, were shown to be consistent in 66%, but were contrary with language paradigms in some subjects. The rest contents made no significant effect on dominant language dominance determination, but the success rates of the dominant language dominances determined from 4 language paradigms were higher in reading the meaningless letter (100%, n=9) than in only seeing "+" on screen at the rest task (78%, n=7). CONCLUSION: High detection rates of Broca and Wernicke areas and high reproducibility of hemispheric language dominance in 4 different language paradigms showed functional MR imaging of our word generation paradigms was reliable and may be clinically useful. However, some inconsistency of hemispheric language dominance with language paradigms or the rest contents suggests that robust and reliable determination of language lateralization may need the performance of different paradigm types or the consideration of rest contents.

Relationships Between Hemispheric Dominance Cognitive Styles and Big Five Personality Traits / 中国临床心理学杂志

Objective: Relationships between hemispheric dominance cognitive styles and Big Five personality traits were investigated.Methods: 86 students participated in this study.By responses to Human Information Processing Survey,32 students were identified as the left hemispheric dominance style group,28 students the right hemispheric dominance style group,and 26 students the integrated dominance style group.All groups were administrated to responses to the NEO-PI-R scales.Results: The left hemispheric group had higher neuroticism and conscientiousness than the right hemispheric dominance group and integrated groups.The right hemispheric group showed more openness and extraversion than the left hemispheric group.The integrated hemispheric group showed more extraversion than the left hemispheric group,and more conscientiousness than the right group.Conclusion: Hemispheric dominance cognitive styles are related to neuroticism,extraversion,openness and conscientiousness.