Takeda N, Hashikawa K, Moriwaki H, Oku N, Koizuka I, Kitahara T, Taya N, Kubo T, Nishimura T
Department of Otolaryngology, Osaka University Medical School, Japan.
J Vestib Res. 1996 Mar-Apr;6(2):127-34.
The effects of caloric vestibular stimulation on regional cerebral blood flow (rCBF) of the parietal and temporal cortex were examined in 10 healthy volunteers. The consecutive 99mTe-hexamethyl-propyleneamine oxime (99mTc-HMPAO) single-photon emission computed tomography (SPECT) method with region of interest analysis was used. Changes in rCBF induced by caloric stimulation with cold air (25 degrees C) were evaluated in comparison with those induced by control stimulation with air at body temperature (37 degrees C). Caloric stimulation with cold air induced vertigo in 4 subjects, dizziness in 2, and no sensation of self-motion in the remaining 4 subjects, whereas, control stimulation did not induce the sensation of self-motion in any subject. Although both parietal and temporal rCBF were slightly decreased during caloric stimulation, a correlation could be established between the magnitude of left-right differences in change of parietal rCBF and the degree of self-motion perception induced by cold-air caloric stimulation, as compared to control stimulation. Left-right differences in change of parietal rCBF in subjects with vertigo during caloric stimulation were significantly higher than those in subjects without any sensation of self-motion. In contrast, there was no correlation between the magnitude of left-right difference in change of parietal rCBF and maximum slow phase eye velocity induced by caloric stimulation. These findings suggest that the parietal lobe is involved in the perception of vertigo due to vestibular stimulation, but not in the vestibulo-ocular reflex.
在10名健康志愿者中研究了热前庭刺激对顶叶和颞叶皮质局部脑血流量（rCBF）的影响。采用连续99m锝-六甲基丙烯胺肟（99mTc-HMPAO）单光子发射计算机断层扫描（SPECT）方法并进行感兴趣区分析。将冷空气（25摄氏度）热刺激诱导的rCBF变化与体温（37摄氏度）空气对照刺激诱导的变化进行比较评估。冷空气热刺激在4名受试者中诱发眩晕，2名受试者出现头晕，其余4名受试者无自我运动感觉，而对照刺激在任何受试者中均未诱发自我运动感觉。虽然热刺激期间顶叶和颞叶的rCBF均略有下降，但与对照刺激相比，顶叶rCBF变化的左右差异幅度与冷空气热刺激诱发的自我运动感知程度之间可建立相关性。热刺激期间出现眩晕的受试者顶叶rCBF变化的左右差异显著高于无任何自我运动感觉的受试者。相比之下，顶叶rCBF变化的左右差异幅度与热刺激诱发的最大慢相眼速度之间无相关性。这些发现表明，顶叶参与了前庭刺激引起的眩晕感知，但不参与前庭眼反射。
