Is dichotic word listening a valid predictor of cerebral language dominance?

Abstract

Although the pattern of ear asymmetry derived from dichotically presented verbal stimuli is used to predict cerebral language dominance, the reliability of this procedure for individual patients has not been adequately established. To determine the accuracy with which verbal dichotic stimuli can predict cerebral language dominance, dichotic word listening performances of 106 patients whose language dominance had been determined by Wada (intracarotid amobarbital) testing were examined. On a group level, ear advantages were in the expected direction, however, no statistically significant differences between left, bilateral, and right language dominance patients were obtained. Predicting side of language dominance was even more ineffective in the individual patient regardless of ear asymmetry criterion. Results suggest that the dichotic word listening task employed in this study is not a valid predictor of cerebral language dominance in adults. Thus, caution should be exercised when inferring language lateralization based solely upon dichotic word listening performance.     

黄蜂蜇伤致急性肾功能衰竭1例

1病例报告患者王某，女，62岁，农民．1998-09-15急诊人院．人院前3d被一群黄蜂蜇伤头面部、颈、肩背部、胸部及四肢，全身共蜇80余个部位，蜇后3h上述部位明显肿胀疼痛，头痛、恶心、呕吐、烦躁不安、嗜睡、乏力，胸闷并出现全身搔痒，48h后出现少尿继而无尿，遂人我院．...     

Lack of effect of norepinephrine on cranial haemodynamics and headache in healthy volunteers

Stress is a provoking factor for both tension-type headache and migraine attacks. In the present single-blind study, we investigated if stress induced by norepinephrine (NE) could elicit delayed headache in 10 healthy subjects and recorded the cranial arterial responses. NE at a dose of 0.025 µg kg⁻¹ min⁻¹ or placebo was infused for 90 min and the headache was followed for 14 h. Blood flow velocity in the middle cerebral artery (measured with transcranial Doppler) and diameters of the temporal artery and the radial artery (measured with ultrasound) were followed for 2 h. There were no changes in these arterial parameters after NE. In both treatment groups three subjects developed delayed headaches. Thus, stress by NE infusion did not result in delayed headache.     

应用均匀设计研究2-甲基-5-巯基-1,3,4-噻二唑制备工艺

应用均匀于标题化合物工艺研究中，以乙酸乙酸和水合肼于二甲苯中反应，加入ＣＳ２，直接加热，一步环合成标题化合物，总收率达７５．５％。     

The relationship between corpus callosum size and forebrain volume

Using high-resolution in vivo magnetic resonance morphometry we measured forebrain volume (FBV), midsagittal size of the corpus callosum (CC) and four CC subareas in 120 young and healthy adults (49 women, 71 men). We found moderate linear and quadratic correlations, indicating that the CC and all CC subareas increase with FBV both in men and women (multiple r2 ranging from 0.10 to 0.28). Allometric equations revealed that these increases were less than proportional to FBV (r2 ranging from 0.02 to 0.30). Absolute CC measurements, as well as CC subareas relative to total CC or FBV (the latter measures termed the CC ratios), were further analyzed with regard to possible effects of handedness, gender, or handedness by gender interaction. Contrary to previous reports, left-handers did not show larger CC measurements compared to right-handers. The only apparent influence of gender was on the CC ratios, which were larger in women. However, smaller brains had larger CC ratios which were mainly independent of gender, a result of the less than proportional increase of callosal size with FBV. We suggest that the previously described gender differences in CC anatomy may be better explained by an underlying effect of brain size, with larger brains having relatively smaller callosa. This lends empirical support to the hypothesis that brain size may be an important factor influencing interhemispheric connectivity and lateralization.