These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Slow saccades in spinocerebellar degeneration.
    Author: Zee DS, Optican LM, Cook JD, Robinson DA, Engel WK.
    Journal: Arch Neurol; 1976 Apr; 33(4):243-51. PubMed ID: 1083233.
    Abstract:
    Two patients with spinocerebellar degeneration made abnormally slow horizontal refixations. One patient produced quick phases of nystagmus with identical maximum velocities, suggesting her refixations were abnormal saccades and not voluntary pursuit movements. In response to double target jumps, neither patient showed an obligatory refractory period after each saccade; they responded to every target movement after one reaction time. Their slow refixations were not preprogrammed since they could be modified in flight. To reconcile these observations with normal saccadic behavior, we hypothesized a neural network that made saccades by driving the eyes to an orbital position rather than preprogramming a distance for movement. Computer simulation of this model produced both realistically appearing normal saccades and, when appropriately "lesioned" to simulate a loss of saccadic "burst" neurons in the pontine reticular formation, slow saccades that could be modified in flight.
    [Abstract] [Full Text] [Related] [New Search]