INERTIAL REPRESENTATION OF ANGULAR MOTION IN THE VESTIBULAR SYSTEM RHESUS-MONKEYS .1. VESTIBULOOCULAR REFLEX
INERTIAL REPRESENTATION OF ANGULAR MOTION IN THE VESTIBULAR SYSTEM RHESUS-MONKEYS .1. VESTIBULOOCULAR REFLEX
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DOI：
10.1152/jn.1994.71.3.1222
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发表时间：
1994-03-01
影响因子：
2.5
通讯作者：
HESS, BJM
中科院分区：
文献类型：
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作者：
ANGELAKI, DE;HESS, BJM
1.在6只恒河猴中，以恒定速度（+/-90度/s）绕垂直于地球的轴旋转后，立即施加快速、短暂、被动的头部和身体倾斜，研究前庭眼反射（VOR）的空间组织。两个备选假设进行了调查，用于编码角运动的参考帧。1)如果前庭系统是在以头为中心的坐标系中组织的，则旋转后的眼速度将始终沿着施加的头部角加速度的方向衰减。2)或者，如果前庭系统编码惯性的角运动，重力为中心的坐标，旋转后的眼速度将沿着重力方向衰减。水平VOR的研究是在猴子直立的情况下进行的。俯仰（滚转）倾斜远离直立引起了一个短暂的垂直（扭转）VOR和缩短的时间常数的水平旋转后慢相速度。此外，正交扭转（俯仰倾斜后）或垂直（滚转倾斜后）的响应逐渐建立。结果，眼球速度矢量在侧倾（俯仰）平面中瞬时偏离，然后在俯仰（侧倾）头部平面中沿与重力相同的方向逐渐旋转，直到正交分量达到峰值。随后，剩余的旋转后眼速度沿沿着平行于重力的直线衰减。水平旋转后反应的时间常数在直立位最大（21.5 +/- 5.7 s，平均值+/- SD），在倾斜至俯卧位（3.8 +/- 0.7 s）、仰卧位（4.5 +/- 1.2 s）和耳下位（5.2 +/- 1.6 s）后最小。类似的依赖于头部方向相对于重力的特征合成的眼速度矢量的动态在俯仰和滚动平面。用仰卧位或俯卧位的猴子研究扭转VOR。俯仰（yawl）从仰卧或俯卧位向直立（耳下）位倾斜引起瞬时垂直（水平）VOR，缩短扭转后旋转反应的时间常数，同时水平（垂直）正交分量缓慢建立。结果，眼球速度矢量在俯仰（偏航）平面中逐渐旋转，直到正交分量达到峰值。随后，剩余的旋转后眼速度沿着平行于重力的直线衰减。仰卧位/俯卧位扭转后旋转反应的时间常数为16.5 ± 6.8 s。从仰卧位/俯卧位向直立位倾斜后，时间常数降低，倾斜至直立位后时间常数最小（2.7 +/- 0.7 s）。在朝向倒置位置倾斜后，时间常数增加，并且在测试的最大倾斜角度（从仰卧/俯卧位置头向下+/-60度）下最长。在偏航平面倾斜后，时间常数随着动物向耳下位置倾斜而降低，在耳下位置扭转VOR时间常数变得最小（5.3 +/- 2.2 s）。垂直VOR检查在耳朵向下的位置。滚转（yawl倾斜从耳朵向下向直立（仰卧/俯卧）位置缩短了垂直旋转后慢相速度的时间常数，而正交水平（滚转倾斜后）或扭转（偏航倾斜后）分量缓慢建立。结果，眼球速度矢量在滚转（偏航）平面内逐渐旋转，远离俯仰头轴，直到残余旋转后速度沿沿着一条近似平行于重力的线衰减。在仰卧/俯卧或耳朵向下位置时最大。对于扭转和垂直VOR，在偏航平面倾斜后，调制周期是倾斜角的一半，在俯仰和滚转平面倾斜后，调制周期取中间值。
1. The spatial organization of the vestibuloocular reflex (VOR) was studied in six rhesus monkeys by applying fast, shortlasting, passive head and body tilts immediately after constant-velocity rotation (+/-90 degrees/s) about an earth-vertical axis. Two alternative hypotheses were investigated regarding the reference frame used for coding angular motion. 1) If the vestibular system is organized in head-centered coordinates, postrotatory eye velocity would decay invariably along the direction of applied head angular acceleration. 2) Alternatively, if the vestibular system codes angular motion in inertial, gravity-centered coordinates, postrotatory eye velocity would decay along the direction of gravity.2. Horizontal VOR was studied with the monkeys upright. Pitch (roll) tilts away from upright elicited a transient vertical (torsional) VOR and shortened the time constant of the horizontal postrotatory slow phase velocity. In addition, an orthogonal torsional (after pitch tilts) or vertical (after roll tilts) response gradually built up. As a result, the eye velocity vector transiently deviated in the roll (pitch) plane and then gradually rotated in the same direction as gravity in the pitch (roll) head plane until the orthogonal component reached a peak value. Subsequently, the residual postrotatory eye velocity decayed along a line parallel to gravity.3. The time constant of the horizontal postrotatory response was maximal in upright position (21.5 +/- 5.7 s, mean +/- SD) and minimal after tilts to prone (3.8 +/- 0.7 s), supine (4.5 +/- 1.2 s), and ear-down (5.2 +/- 1.6 s) positions. A similar dependence on head orientation relative to gravity characterized the dynamics of the resultant eye velocity vector in the pitch and roll planes.4. Torsional VOR was studied with the monkeys in supine or prone position. Pitch (yawl tilts from the supine or prone position toward upright (ear-down) position elicited a transient vertical (horizontal) VOR and shortened the time constant of the torsional postrotatory response while a horizontal (vertical) orthogonal component slowly built up. As a result the eye velocity vector gradually rotated in the pitch (yaw) plane until the orthogonal component reached a peak value. Subsequently residual postrotatory eye velocity decayed along a line parallel to gravity.5. The time constant of the torsional postrotatory response in supine/prone positions was 16.5 +/- 6.8 s. After tilts from supine/ prone positions toward upright position, time constants decreased and were minimal after tilts to upright position (2.7 +/- 0.7 s). After tilts toward upside-down position, time constants increased and were longest at the largest tilt angle tested (+/- 60 degrees head-down from supine/prone positions). After tilts in the yaw plane, time constants decreased as animals were tilted toward ear-down positions where torsional VOR time constants became minimal (5.3 +/- 2.2 s).6. Vertical VOR was examined in ear-down positions. Roll (yawl tilts from ear-down toward upright (supine/prone) position shortened the time constant of the vertical postrotatory slow phase velocity while an orthogonal horizontal (after roll tilts) or torsional (after yaw tilts) component slowly built up. As a result the eye velocity vector gradually rotated in the roll (yaw) plane away from the pitch head axis until residual postrotatory velocity decayed along a line approximately parallel to gravity. aximal in supine/prone or ear-down positions. For torsional and vertical VOR the period of modulation was half that of the tilt angle after tilts in the yaw plane and took intermediate values after tilts in the pitch and roll planes.