On the neurophysiology of eye movements

On the neurophysiology

of eye movements

Th. J. M. Breuer, P. G. W. M. Wuisman and J. J. Korten (Sittard) Much of our present knowledge of the regulation of eye movements is based on gross stimulation and lesion experiments. Recently, however, refined neurophysiological and histochemical techniques are developed, using micro-electrodes and tracers respectively. These

also

contribute

tosensory

impulses

generation

of eye movements.

relations between hemispherical, brain stem structures result

to

Complex

the

inter-

cerebellar and in different

premotor eye movement commands. Principally, the eye movements can be divided into four Smooth Pursuit, Saccadic, different types: Optokinetic movements

and Vestibular Compensatory. in the horizontal and vertical

new techniques provide more detailed information on the mechanisms and structures inguided ocular motor volved in visually

are obviously

Additionally, electro oculographic response. methods may contribute to better understanding of this response. Afferent visual information gives rise to both voluntary and involuntary eye

observations. The above mentioned structures and mechanisms are discussed. The authors suggest further clinical electro oculographic investigations in the complex field of eye movements and its disorders.

movements.

Afferent

vestibular

and

soma-

generated

brain stem reticular by experimental

in different

Eye plane

parts of the

formation. as demonstrated and clinical pathological

Clinical analysis of ocular lateropulsion in Wallenberg’s syndrome L. Crevits and H. vander Eecken (Ghent) The occurrence and direction of ocular lateropulsion was studied in a series of 18 patients with Wallenberg’s syndrome. The basic disturbance of ocular lateropulsion consists of a lateral vector of fixed direction superimposed on versional eye movements. At the bedside this can be observed during horizontal refixation saccades as ipsilateral hypermetria and contralateral hypometria,

the side of infarction. Eleven patients showed a combination of horizontal dysmetria with angular deflection of vertical refixation saccades. In nine patients horizontal and vertical saccadic lateropulsion was associated with lateroversion under closed eyelids. The lateral bias was always directed to the affected bulbar side. Although further systematic study in other posterior fossa disorders is needed, it can be concluded that, even by simple clinical inspec-

while vertical refixation saccades are deflected ipsilaterally and have an angular trajectory. When fication is excluded, the eyes deviate to

tion. ocular lateropulsion finding with a reliable Wallenberg’s syndrome.

is a rather regular lateralizing value in

New aspects in diagnostic and therapeutic procedures in neurosyphilis E. Ch. Wolters (Amsterdam) Primary and secondary syphilis are generally speaking not followed by subsequent stages of this disease if adequately treated with Penidural i.m. 3 x 2.4 million I.U. at day 1, 8 and 15. As a rule investigation of C.S.F. is not necessary in those stages. Before treatment with Penidural, as mentioned above, in all other stages of syphilis (e.g.

lues latens, undertermined lues) and (a)symptomatic neurosyphilis has to be excluded. A specific syphilitic anti-body production against treponema pallidum has to be established in the central nervous system, to diagnose an (a)-symptomatic neurosyphilis. Proving specific anti-bodies in the C.S.F. is not an incontestable evidence for production of such anti-bodies within the C.N.S. (bloodC.S.F. barrier leakage). 69