Influence of target size on vertical gaze palsy in a pathologically proven case of progressive supranuclear palsy

Barry M. Seemungal, Mary Faldon, Tamas Revesz, Andrew J. Lees, David Samuel Zee, Adolfo M. Bronstein

Research output: Contribution to journalArticle


We document a new oculomotor phenomenon in a patient with pathologically proven progressive supranuclear gaze palsy (PSP), namely that vertical gaze excursion improves with larger pursuit targets. We used computerised video-oculography during vertical smooth pursuit eye movements (SPEM) of circular targets of diameter 0.16 degrees and 16 degrees, sinusoidally oscillating at 0.08 Hz (peak-to-peak amplitude 49 degrees). Increasing target size improved vertical gaze excursion from 10 degrees to 25 degrees. There was no concomitant increase in slow phase eye velocity. The findings could be explained by a potentiation of the position control mechanism of pursuit by target size due to increased activation of brainstem pursuit-opto-kinetic pathways and to higher order attentional mechanisms. This observation may be useful in the clinical assessment of PSP patients with severe neck rigidity in whom the doll's head-eye manoeuvre cannot be performed by comparing the degree of vertical gaze palsy during smooth pursuit testing between at least two differently sized targets and observing whether there is a larger excursion in response to a large target such as a newspaper.

Original languageEnglish (US)
Pages (from-to)818-822
Number of pages5
JournalMovement disorders : official journal of the Movement Disorder Society
Issue number7
StatePublished - Jul 1 2003



  • Improved vertical gaze palsy
  • Progressive supranuclear palsy
  • Target size

ASJC Scopus subject areas

  • Clinical Neurology
  • Neuroscience(all)

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