The simple observation that started our experiments has an age-old tradition in the history of science. Aristotle (384-322 B.c.) was presumably the first to describe that after looking into the sun or another bright light, a long-lasting afterimage persists and is seen thereafter in the respective line of sight.’ Such an afterimage is, of course, a perfectly stabilized retinal image; however, it can be seen to change its position in the extrapersonal space whenever the eyes move voluntarily. A small afterimage placed within 2” to 3’ around the fovea centralis can be used to elicit smooth-pursuit eye movements in darkness when one tries to fixate it intentionally. During the pursuit movements, the afterimage is seen moving in the direction of the eye movement~.’.~.~ This von Helmholtz afterimage movement illusion was explained by 19th century physiologists as being caused by a central interaction of premotor commands controlling gaze movement and the afferent visual-signal f l o ~ . ’ . ~ . ~ Visual movement perceived with a stimulus pattern that is stationary on the retina but with moving eyes is called efferent movement perception, while the visual movement elicited by a change in position of the retinal stimuli is called afferent movement p e r ~ e p t i o n . ~ . ~ To our knowledge, the first block diagram of the interaction between afferent sensory signals and the corollary discharges of efferent motor signals was published in the general scheme “MerkweltWirkwelt-Koppelung” by J . von Uexkull.’ This model [FIGURE la ) contains the essential properties that later became known as the efference copy hypothean efference copy of the motor commands interacts with the afferent sensory-signal flow; the result of this interaction constitutes the percept and simultaneously the signals driving the pursuit mechanisms. Despite its long existence, the efference copy interaction model rarely has been analyzed quantitatively and no systematic experiments have been performed with nonhuman primates. The afterimage paradigm is difficult to apply in animal experiments. We have therefore, during the last eight years, used another paradigm [FIGURE lb).’4.’5 A row of equally spaced stationary black and white stripes or black dots of the spatial period P, is illuminated stroboscopically at the flash frequency fs [flash duration half-time, 56 pseconds). When the center sis~10.11,1Z.13
[1]
B. Cohen,et al.
Quantitative analysis of the velocity characteristics of optokinetic nystagmus and optokinetic after‐nystagmus
,
1977,
The Journal of physiology.
[2]
V Henn,et al.
Visual-vestibular interaction in motion perception and the generation of nystagmus.
,
1980,
Neurosciences Research Program bulletin.
[3]
G. Kommerell,et al.
Über die visuelle regelung der okulomotorik: Die optomotorische wirkung exzentrischer nachbilder
,
1971
.
[4]
C Lamontagne,et al.
A New Experimental Paradigm for the Investigation of the Secondary System of Human Visual Motion Perception
,
1973
.
[5]
B. Julesz,et al.
Differences between monocular and binocular stroboscopic movement perception.
,
1968,
Vision research.
[6]
R. Sperry.
Neural basis of the spontaneous optokinetic response produced by visual inversion.
,
1950,
Journal of comparative and physiological psychology.
[7]
R Täumer,et al.
Investigations of the eye tracking system through stabilized retinal images.
,
1972,
Bibliotheca ophthalmologica : supplementa ad ophthalmologica.
[8]
J. Needham.
Theoretische Biologie
,
1933,
Nature.
[9]
O.-J. Grüsser,et al.
Bewegungswahrnehmung und Augenbewegungen bei Flickerbelichtung unbewegter visueller Muster
,
1978
.
[10]
H. Collewijn.
Eye‐ and head movements in freely moving rabbits.
,
1977,
The Journal of physiology.
[11]
R. Jung.
Visual Perception and Neurophysiology
,
1973
.
[12]
H. Collewijn,et al.
Binocular retinal image motion during active head rotation
,
1980,
Vision Research.
[13]
Aristotle,et al.
On the soul ; Parva naturalia ; On breath
,
1957
.