TY - JOUR

T1 - An effect of structured backgrounds on smooth pursuit eye movements in patients with cerebral lesions

AU - Lawden, Mark

AU - Bagelmann, H.

AU - Crawford, Trevor

AU - Matthews, T. D.

AU - Kennard, Christopher

PY - 1995

Y1 - 1995

N2 - The oculomotor smooth pursuit system is driven by the slipof the target image upon the retina arising from errors inmatching eye and target velocities. However, pursuit of anobject moving against a structured background causes mostretinal flow to be in the direction opposite to target movement.Central mechanisms allow these distracting signals to beoverridden effortlessly. To isolate the anatomical substrateof this capacity we studied the effect of the presence of astructured background upon smooth pursuit in 26 patientswith focal cerebral lesions. In normal control subjects, studiesconfirmed that a background has little effect upon pursuit.Eye movements were recorded by the scleral search coilmethod or by infra-red oculography. The target was abright spot moving horizontally in a triangular waveformof amplitude ±11.25° visual angle, at either 10, 20, 30 or36.5°/s. Data were collected in darkness and with a structuredbackground: 14 patients showed a significant reduction ofgain with a structured background, while the remaining 12showed little or no effect. Comparison of the location of thecerebral lesions in these two groups suggested that lesionsin the inferior parietal cortex (area 40) or in white mattercontaining parieto-frontal connections result in disruption ofpursuit in the presence of a background.

AB - The oculomotor smooth pursuit system is driven by the slipof the target image upon the retina arising from errors inmatching eye and target velocities. However, pursuit of anobject moving against a structured background causes mostretinal flow to be in the direction opposite to target movement.Central mechanisms allow these distracting signals to beoverridden effortlessly. To isolate the anatomical substrateof this capacity we studied the effect of the presence of astructured background upon smooth pursuit in 26 patientswith focal cerebral lesions. In normal control subjects, studiesconfirmed that a background has little effect upon pursuit.Eye movements were recorded by the scleral search coilmethod or by infra-red oculography. The target was abright spot moving horizontally in a triangular waveformof amplitude ±11.25° visual angle, at either 10, 20, 30 or36.5°/s. Data were collected in darkness and with a structuredbackground: 14 patients showed a significant reduction ofgain with a structured background, while the remaining 12showed little or no effect. Comparison of the location of thecerebral lesions in these two groups suggested that lesionsin the inferior parietal cortex (area 40) or in white mattercontaining parieto-frontal connections result in disruption ofpursuit in the presence of a background.

KW - smooth pursuit

KW - parietal lobe

KW - optokinetic response

KW - background effect

U2 - 10.1093/brain/118.1.37

DO - 10.1093/brain/118.1.37

M3 - Journal article

VL - 118

SP - 37

EP - 48

JO - Brain

JF - Brain

SN - 0006-8950

IS - 1

ER -