Purpose: To investigate the spatiotemporal evolution of cortical activation during the initiation of optokinetic nystagmus using magnetoencephalography. Background: Previous imaging studies of optokinetic nystagmus in humans using positron emission tomography and functional magnetic resonance imaging discovered activation of a large set of cortical and subcortical structures during steady-state optokinetic stimulation, but did not provide information on the temporal dynamics of the initial response. Imaging studies have shown that cortical areas responsible for vision in occipital and temporo-occipital areas are involved, i.e. cortical areas control optokinetic stimulation in humans. Magnetoencephalography provides measures that reflect neural ensemble activity in the millisecond time scale, allowing the identification of early cortical components of visuomotor integration. Design/Methods: We studied neuromagnetic cortical responses during the initiation of optokinetic nystagmus in 6 right-handed healthy subjects. Neuromagnetic activity was recorded with a whole-head magnetoencephalograph, consisting of 143 planar gradiometers. Results: The mean (±SD) latency between stimulus onset and initiation of optokinetic nystagmus was 177.7 ± 59 ms. Initiation of optokinetic nystagmus evoked an early component in the primary visual cortex starting at 40-90 ms prior to the onset of the slow phase of nystagmus. Almost simultaneously an overlapping second component occurred bilaterally in the temporo-occipital area (visual motion areas), pronounced in the right hemisphere, starting at 10-60 ms prior to the slow-phase onset. Both components showed long-duration activity lasting for up to 100 ms after slow-phase onset. Conclusions: Our findings suggest that the initiation of optokinetic nystagmus induces early cortical activation in the occipital cortex and almost simultaneously bilaterally in the temporo-occipital cortex. These cortical regions might represent essential areas for the monitoring of retinal slip.

Keywords:
Magnetoencephalography, Optokinetic nystagmus, Visuomotor integration, Cortical activation, Vestibular system
1.
Ahlfors SP, Simpson GV, Dale AM, et al: Spatiotemporal activity of a cortical network for processing visual motion revealed by MEG and fMRI. J Neurophysiol 1999;82:2545-2555.
2.
Bense S, Janusch B, Schlindwein P, et al: Direction-dependent visual cortex activation during horizontal optokinetic stimulation (fMRI study). Hum Brain Mapp 2006;27:296-305.
3.
Bense S, Stephan T, Bartenstein P, et al: Fixation suppression of optokinetic nystagmus modulates cortical visual-vestibular interaction. Neuroreport 2005;16:887-890.
4.
Brandt T, Allum JH, Dichgans J: Computer analysis of optokinetic nystagmus in patients with spontaneous nystagmus of peripheral vestibular origin. Acta Otolaryngol 1978;86:115-122.
5.
Bruce CJ, Goldberg ME, Bushnell MC, Stanton GB: Primate frontal eye fields. II. Physiological and anatomical correlates of electrically evoked eye movements. J Neurophysiol 1985;54:714-734.
6.
Bucher SF, Dieterich M, Seelos KC, Brandt T: Sensorimotor cerebral activation during optokinetic nystagmus. Neurology 1997;49:1370-1377.
7.
Dieterich M, Bense S, Stephan T, et al: fMRI signal increases and decreases in cortical areas during small-field optokinetic stimulation and central fixation. Exp Brain Res 2003;148:117-127.
8.
Dieterich M, Brandt T: Brain activation studies on visual vestibular and ocular motor interaction. Curr Opin Neurol 2000;13:13-18.
9.
Dieterich M, Bucher SF, Seelos KC, Brandt T: Cerebellar activation during optokinetic stimulation and saccades. Neurology 2000;54:148-155.
10.
Galati G, Pappata S, Pantano P, et al: Cortical control of optokinetic nystagmus in humans: a positron emission tomography study. Exp Brain Res 1999;126:149-159.
11.
Gulyás S, Pálvölgyi L, Kamondi A, Szirmai I: EEG correlates of subcortical optokinetic nystagmus. Clin Neurophysiol 2007;118:551-557.
12.
Ilg U: The role of areas MT and MST in coding of visual motion underlying the execution of smooth pursuit. Vision Res 2008;48:2062-2069.
13.
Kandori A, Oe H, Miyashita K, et al: Magneto-encephalographic measurement of neural activity during period of vertigo induced by cold caloric stimulation. Neurosci Res 2003;46:281-288.
14.
Kim H, Chung CK, Hwang H: Magnetoencephalography in pediatric epilepsy. Korean J Pediatr 2013;56:431-438.
15.
Nevalainen P, Lauronen L, Pihko E: Development of human somatosensory cortical functions - what have we learned from magnetoencephalography: a review. Front Hum Neurosci 2014;8:158.
16.
Pavlou M: The use of optokinetic stimulation in vestibular rehabilitation. J Neurol Phys Ther 2010;34:105-110.
17.
Prochnow N, Lee P, Hall WC, Schmidt M: In vitro properties of neurons in the rat pretectal nucleus of the optic tract. J Neurophysiol 2007;97:3574-3584.
18.
Sasaki Y, Murakami I, Cavanagh P, Tootell RH: Human brain activity during illusory visual jitter as revealed by functional magnetic resonance imaging. Neuron 2002;35:1147-1156.
19.
Schall JD: On the role of frontal eye field in guiding attention and saccades. Vision Res 2004:44:1453-1467.
20.
Stoeckel MC, Pollok B, Schnitzler A, Seitz RJ: Studying the human somatosensory hand area: a new way to compare fMRI and MEG. Neurosci Methods 2007;164:280-291.
21.
Zhu M, Hertle RW, Kim CH, et al: Effect of binocular rivalry suppression on initial ocular following responses. J Vis 2008;8:1-11.
© 2015 S. Karger AG, Basel
2015
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