Reference frames for spinal proprioception: Kinematics based or kinetics based?

被引:44
作者
Bosco, G [1 ]
Poppele, RE [1 ]
机构
[1] Univ Minnesota, Dept Neurosci, Minneapolis, MN 55455 USA
关键词
D O I
10.1152/jn.2000.83.5.2946
中图分类号
Q189 [神经科学];
学科分类号
071006 ;
摘要
This second paper of the series deals with another issue regarding sensorimotor representations in the CNS that has received much attention, namely the relative weighting of kinematic and kinetic representations. The question we address here is the contribution of muscle tension afferent information in dorsal spinocerebellar tract (DSCT) sensory representations of foot position. In Eve anesthetized cats, we activated major hindlimb muscle groups using electrical stimulation of ventral root filaments while passively positioning of the left hind foot throughout its workspace. In general, as the parameters of the joint angle covariance planes indicated, muscle stimulation did not significantly change hindlimb geometry. We analyzed the effects of the muscle stimulation on DSCT neuronal activity within the framework of a kinematic-based representation of foot position. We used a multivariate regression model described in the companion paper, wherein indicators of the experimental condition were added as firing rate predictors along with the limb axis length and orientation to account for possible effects of muscle stimulation. The results indicated that the response gain of 35/59 neurons studied (59%) was not changed by the muscle activations, although most neurons showed some change in their overall firing level with stimulation of one or more muscles. Most of the neurons responded to pseudorandom stimulation of the same muscle groups with complex temporal patterns of activity. For a subpopulation of 42 neurons, we investigated the extent to which their representation of foot position was affected by a rigid constraint of the knee joint and at least one type of muscle stimulation. Although they could be divided into four subgroups based on significance level cutoffs for the constraint or stimulation effect, these effects were in fact quite distributed. However, when we examined the preferred directions of spatial tuning relative to the limb axis position, we found it was unchanged by muscle stimulation for most cells. Even in those cases in which response gain was altered by muscle stimulation, the cell's preferred direction generally was unaltered. The invariance of preferred direction with muscle stimulation lead us to the conclusion that the reference frame for DSCT coding may be based primarily on limb kinematics.
引用
收藏
页码:2946 / 2955
页数:10
相关论文
共 17 条
[1]   ENCODING OF SPATIAL LOCATION BY POSTERIOR PARIETAL NEURONS [J].
ANDERSEN, RA ;
ESSICK, GK ;
SIEGEL, RM .
SCIENCE, 1985, 230 (4724) :456-458
[2]   BROAD DIRECTIONAL TUNING IN SPINAL PROJECTIONS TO THE CEREBELLUM [J].
BOSCO, G ;
POPPELE, RE .
JOURNAL OF NEUROPHYSIOLOGY, 1993, 70 (02) :863-866
[3]   Representation of multiple kinematic parameters of the cat hindlimb in spinocerebellar activity [J].
Bosco, G ;
Poppele, RE .
JOURNAL OF NEUROPHYSIOLOGY, 1997, 78 (03) :1421-1432
[4]   Representation of passive hindlimb postures in cat spinocerebellar activity [J].
Bosco, G ;
Rankin, A ;
Poppele, R .
JOURNAL OF NEUROPHYSIOLOGY, 1996, 76 (02) :715-726
[5]   Temporal features of directional tuning by spinocerebellar neurons: Relation to limb geometry [J].
Bosco, G ;
Poppele, RE .
JOURNAL OF NEUROPHYSIOLOGY, 1996, 75 (04) :1647-1658
[6]   Reference frames for spinal proprioception: Limb endpoint based or joint-level based? [J].
Bosco, G ;
Poppele, RE ;
Eian, J .
JOURNAL OF NEUROPHYSIOLOGY, 2000, 83 (05) :2931-2945
[7]  
HOLMQVIST B, 1956, ACTA PHYSIOL SCAND, V38, P76
[8]   INHIBITION OF DORSAL SPINOCEREBELLAR TRACT CELLS BY INTERNEURONES IN UPPER AND LOWER LUMBAR SEGMENTS IN THE CAT [J].
HONGO, T ;
JANKOWSKA, E ;
OHNO, T ;
SASAKI, S ;
YAMASHITA, M ;
YOSHIDA, K .
JOURNAL OF PHYSIOLOGY-LONDON, 1983, 342 (SEP) :145-159
[9]  
KETTNER RE, 1988, J NEUROSCI, V8, P2938
[10]   INDEPENDENT CONTROL OF LIMB POSITION AND CONTACT FORCES IN CAT POSTURE [J].
LACQUANITI, F ;
MAIOLI, C .
JOURNAL OF NEUROPHYSIOLOGY, 1994, 72 (04) :1476-1495