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Illusory shadow person causing paradoxical gaze deviations during temporal lobe seizures
M Zijlmans1, P van Eijsden, C H Ferrier
1Department of Neurology, Rudolf Magnus Institute of Neuroscience, University Medical Center, Utrecht, The Netherlands. g.j.m.zijlmans@umcutrecht.nl
Journal of Neurology, Neurosurgery, and Psychiatry
|May 19, 2009
Summary
Frontal eye field activation during seizures causes gaze deviation. Paradoxical head deviation in temporal lobe seizures may stem from illusory experiences and postictal amnesia, offering a novel explanation.
Area of Science:
- Neuroscience
- Epileptology
- Clinical Neurology
Background:
- Ictal gaze and head deviation during seizures are typically lateralized to the seizure onset zone.
- Non-versive head deviation is often attributed to ictal neglect following temporo-parietal area inactivation.
Observation:
- A patient presented with paradoxical non-versive gaze deviation during temporal lobe seizures.
- Electrocortical stimulation induced an urge to look towards an illusory shadow figure.
Findings:
- This case challenges the typical understanding of ictal head deviation lateralization.
- Illusory experiences, potentially masked by postictal amnesia, may explain paradoxical gaze deviations.
Implications:
- Findings suggest a need to consider complex sensory and cognitive phenomena in seizure semiology.
- This research may refine our understanding of the neural basis of gaze control and neglect during epilepsy.
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