Obrig H, Hirth C, Junge-Hülsing J G, Döge C, Wolf T, Dirnagl U, Villringer A
Department of Neurology, Humboldt-Universität zu Berlin, Germany.
J Appl Physiol (1985). 1996 Sep;81(3):1174-83. doi: 10.1152/jappl.1996.81.3.1174.
We studied cerebral hemodynamic response to a sequential motor task in 56 subjects to investigate the time course and distribution of blood oxygenation changes as monitored by near-infrared spectroscopy (NIRS). To address whether response is modulated by different performance velocities, a group of subjects (n = 12) was examined while performing the motor task at 1, 2, and 3 Hz. The results demonstrate that 1) the NIRS response reflects localized changes in cerebral hemodynamics, 2) the response, consisting of an increase in oxygenated hemoglobin concentration [oxy-Hb] and a decrease in deoxygenated hemoglobin concentration ([deoxy-Hb]), is lateralized and increases in amplitude with higher performance rates, and 3) changes in [oxy-Hb] and [deoxy-Hb] differ in time course. Changes in [oxy-Hb] are biphasic, with a fast initial increase and a pronounced poststimulus undershoot. The stimulus-associated decrease in [deoxy-Hb] is monophasic, and response latency is greater. We conclude that NIRS is able to detect even small changes in cerebral hemodynamic response to functional stimulation.
我们对56名受试者进行了研究，以观察其在执行连续运动任务时的脑血流动力学反应，通过近红外光谱技术（NIRS）监测血液氧合变化的时间进程和分布情况。为了探究反应是否受不同运动速度的调节，我们让一组受试者（n = 12）在以1 Hz、2 Hz和3 Hz的频率执行运动任务时接受检测。结果表明：1）NIRS反应反映了脑血流动力学的局部变化；2）该反应由氧合血红蛋白浓度[oxy-Hb]升高和脱氧血红蛋白浓度（[deoxy-Hb]）降低组成，具有侧化现象，且随着运动速度加快幅度增大；3）[oxy-Hb]和[deoxy-Hb]的变化在时间进程上有所不同。[oxy-Hb]的变化呈双相性，最初快速升高，刺激后出现明显的下降。与刺激相关的[deoxy-Hb]降低呈单相性，且反应潜伏期更长。我们得出结论，NIRS能够检测到脑血流动力学对功能刺激的哪怕是微小变化。
