Optokinetic nystagmus in harbor seals (Phoca vitulina)

نویسندگان

  • Frederike D. Hanke
  • Wolf Hanke
  • Klaus-Peter Hoffmann
  • Guido Dehnhardt
چکیده

Harbor seals experience motion due to self-motion and to movement in the external world. However, motion vision has not been studied yet in marine mammals moving in the underwater world. To open up this research, optokinetic nystagmus (OKN) as a basic motion sensing and retinal image stabilizing reflex was studied in four harbor seals during stimulation with moving black-and-white stripe patterns. All seals responded with optokinetic eye movements. Detailed measurements obtained with one animal revealed a moderate gain for horizontal binocular OKN. Monocularly stimulated, the seal displayed a symmetrical OKN with slightly stronger responses to leftward moving stimuli, and, surprisingly, a symmetrical OKN was found in the vertical domain.

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عنوان ژورنال:
  • Vision Research

دوره 48  شماره 

صفحات  -

تاریخ انتشار 2008