当前位置： SCI文献检索 > NEUROPSYCHOLOGIA期刊下所有文献 > fMRI evidence for sensorimotor transformations in human cortex during smooth pursuit eye movements.

fMRI evidence for sensorimotor transformations in human cortex during smooth pursuit eye movements.

Abstract：

:Smooth pursuit eye movements (SP) are driven by moving objects. The pursuit system processes the visual input signals and transforms this information into an oculomotor output signal. Despite the object's movement on the retina and the eyes' movement in the head, we are able to locate the object in space implying coordinate transformations from retinal to head and space coordinates. To test for the visual and oculomotor components of SP and the possible transformation sites, we investigated three experimental conditions: (I) fixation of a stationary target with a second target moving across the retina (visual), (II) pursuit of the moving target with the second target moving in phase (oculomotor), (III) pursuit of the moving target with the second target remaining stationary (visuo-oculomotor). Precise eye movement data were simultaneously measured with the fMRI data. Visual components of activation during SP were located in the motion-sensitive, temporo-parieto-occipital region MT+ and the right posterior parietal cortex (PPC). Motor components comprised more widespread activation in these regions and additional activations in the frontal and supplementary eye fields (FEF, SEF), the cingulate gyrus and precuneus. The combined visuo-oculomotor stimulus revealed additional activation in the putamen. Possible transformation sites were found in MT+ and PPC. The MT+ activation evoked by the motion of a single visual dot was very localized, while the activation of the same single dot motion driving the eye was rather extended across MT+. The eye movement information appeared to be dispersed across the visual map of MT+. This could be interpreted as a transfer of the one-dimensional eye movement information into the two-dimensional visual map. Potentially, the dispersed information could be used to remap MT+ to space coordinates rather than retinal coordinates and to provide the basis for a motor output control. A similar interpretation holds for our results in the PPC region.

journal_name

Neuropsychologia

journal_title

Neuropsychologia

authors

Kimmig H,Ohlendorf S,Speck O,Sprenger A,Rutschmann RM,Haller S,Greenlee MW

doi

10.1016/j.neuropsychologia.2008.02.021

subject

Has Abstract

pub_date

2008-01-01 00:00:00

pages

2203-13

issue

eissn

0028-3932

issn

1873-3514

pii

S0028-3932(08)00079-1

journal_volume

pub_type

杂志文章

在线工具

fMRI evidence for sensorimotor transformations in human cortex during smooth pursuit eye movements.