Localisation of auditory targets during optokinetic nystagmus.
Previous studies have shown that the perceived location of visual stimuli briefly flashed during smooth pursuit, saccades, or optokinetic nystagmus (OKN) is not veridical. We investigated whether these mislocalisations can also be observed for brief auditory stimuli presented during OKN. Experiments were carried out in a lightproof sound-attenuated chamber. Participants performed eye movements elicited by visual stimuli. An auditory target (white noise) was presented for 5 ms. Our data clearly indicate that auditory targets are mislocalised during reflexive eye movements. OKN induces a shift of perceived location in the direction of the slow eye movement and is modulated in the temporal vicinity of the fast phase. The mislocalisation is stronger for look- as compared to stare-nystagmus. The size and temporal pattern of the observed mislocalisation are different from that found for visual targets. This suggests that different neural mechanisms are at play to integrate oculomotor signals and information on the spatial location of visual as well as auditory stimuli.
Königs
Kerstin
K
Department of Neurophysics, Philipps-University Marburg, Renthof 7, D 35032 Marburg, Germany. kerstin.koenigs@physik.uni-marburg.de
Knöll
Jonas
J
Bremmer
Frank
F
D000161:Acoustic Stimulation; D000328:Adult; D000704:Analysis of Variance; D001307:Auditory Perception / Q000502:physiology*; D005260:Female; D006801:Humans; D007088:Illusions; D008297:Male; D017120:Nystagmus, Optokinetic / Q000502:physiology*; D010775:Photic Stimulation; D011597:Psychomotor Performance; D013017:Sound Localization / Q000502:physiology