Engelhardt Huberta, Feddersen Berend, Boetzel Kai, Noachtar Soheyl
Department of Neurology, Klinikum Grosshadern, University of Munich, Marchioninistrasse 15, 81377 Munich, Germany.
Clin Neurophysiol. 2007 Oct;118(10):2282-6. doi: 10.1016/j.clinph.2007.07.008. Epub 2007 Aug 20.
Caloric stimulation leads to a reduction of the cerebral blood flow in the visual cortex. This reduction has been attributed to the suppression of visual input caused by nystagmus induced by caloric stimulation. We investigated the influence of caloric stimulation on transient flash and steady-state flash visual evoked potentials.
Visual evoked potentials to 1 and 10 Hz flash stimulation were recorded in 12 normal subjects at baseline, during nystagmus induced by caloric stimulation with cold water, and after the cessation of nystagmus.
Neither the amplitude of the transient flash visual evoked potentials (1 Hz stimulation) nor the amplitude of the steady-state flash visual evoked potentials (10 Hz stimulation) was influenced by caloric stimulation compared to baseline.
The deactivation of the visual cortex by caloric stimulation does not seem to affect transient flash or steady-state flash visual evoked potentials. Reduction of cerebral blood flow in the visual cortex does not affect the processing of visual qualities (e.g., luminance and pattern).
Caloric stimulation does not reduce the amplitudes of transient flash or steady-state flash visual evoked potentials.
热刺激会导致视觉皮层的脑血流量减少。这种减少归因于热刺激诱发的眼球震颤所引起的视觉输入抑制。我们研究了热刺激对瞬态闪光和稳态闪光视觉诱发电位的影响。
在12名正常受试者中，于基线状态、冷水热刺激诱发眼球震颤期间以及眼球震颤停止后，记录对1Hz和10Hz闪光刺激的视觉诱发电位。
与基线相比，热刺激对瞬态闪光视觉诱发电位（1Hz刺激）的幅度和稳态闪光视觉诱发电位（10Hz刺激）的幅度均无影响。
热刺激使视觉皮层失活似乎并不影响瞬态闪光或稳态闪光视觉诱发电位。视觉皮层脑血流量的减少并不影响视觉质量（如亮度和图案）的处理。
热刺激不会降低瞬态闪光或稳态闪光视觉诱发电位的幅度。
