• We are sorry, but NCBI web applications do not support your browser and may not function properly. More information
Logo of jnnpsycJournal of Neurology, Neurosurgery and PsychiatryCurrent TOCInstructions for authors
J Neurol Neurosurg Psychiatry. Sep 1999; 67(3): 390–394.
PMCID: PMC1736522

A case of thalamic syndrome: somatosensory influences on visual orientation

Abstract

The ability to set a straight line to the perceived gravitational vertical (subjective visual vertical, SVV) was investigated in a 21 year old woman with long standing left hemihypaesthesia due to a posterior thalamic infarct. The putative structures involved were the somatosensory and vestibular thalamus (VPL, VPM) and associative (pulvinar) thalamus. The SVV was normal when seated upright. When lying on her right side, line settings deviated about 17° to the right, which is the normal A-effect. When lying on the hypaesthetic side the mean SVV remained close to true vertical—that is, the A-effect was absent, and there was a large increase in variability of the SVV settings. The findings support the view that the body tilt-induced bias of the SVV (A-effect) is largely mediated by somatosensory afferents. The finding that the A-effect was absent only when lying on the hypaesthetic side suggests that, during body tilt, the somatosensory system participates in visuogravitational orientation.

Full Text

The Full Text of this article is available as a PDF (121K).

Articles from Journal of Neurology, Neurosurgery, and Psychiatry are provided here courtesy of BMJ Group

Formats:

Related citations in PubMed

See reviews...See all...

Cited by other articles in PMC

See all...

Links

  • MedGen
    MedGen
    Related information in MedGen
  • PubMed
    PubMed
    PubMed citations for these articles

Recent Activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...