Session Information
Date: Wednesday, June 22, 2016
Session Title: Ataxia
Session Time: 12:00pm-1:30pm
Location: Exhibit Hall located in Hall B, Level 2
Objective: In order to elucidate the cause of the impaired reading performance.
Background: Deficit in reading performance in patients with spinocerebellar degeneration (SCD) has been characterized not only by impaired articulation, rate, and rhythm but also skipping, translocations, and frequent gaze regressions. The exact cause of this reading impairment is unknown.
Methods: Subjects were 13 SCD patients (SCA6: 3 patients, SCA31: 1 patient, SCA3: 1 patient, multiple system atrophy (MSA):8 patients) and 10 normal age-matched subjects. They read 22 Japanese texts of varying difficulty (intelligibility) presented for a period of 45 seconds on a 17-inch monitor screen, placed 50 cm in front of their eyes. The texts consisted of Chinese characters and Japanese phonograms (hiragana), with each letter subtending a visual angle of 0.6-1.3 degrees. We performed synchronously sampled the voice of the subjects along with the gaze looking at the text while the subjects read the texts aloud, using an video-based eye tracker. For each text, we measured the time required for reading, the average amplitude of saccades, average fixation duration, and the number of saccade per seconds and the number of gaze regressions, as well as the eye voice lead time (the time by which the gaze preceded the voice measured at the location of the text where the voice was just reading).
Results: Reading the texts aloud took longer for SCD patients compared to normal subjects. Overall, the amplitude of saccades was smaller and duration of fixation longer in SCD patients. In both SCD patients and normal subjects, the amplitude of saccades was smaller and duration of fixation longer for more difficult texts. This trend was more pronounced for SCD patients compared to normal subjects. The distribution of fixation as well as the length of eye voice lead was more variable in SCD patients.
Conclusions: Reading texts aloud in SCD may result from the impairment in eye voice coordination.
To cite this abstract in AMA style:
Y. Terao, S. Tokushige, S. Terada, T. Sasaki, M. Hamada, S. Tsuji, Y. Ugawa. Impaired eye voice coordination in spinocerebellar degeneration while reading aloud [abstract]. Mov Disord. 2016; 31 (suppl 2). https://www.mdsabstracts.org/abstract/impaired-eye-voice-coordination-in-spinocerebellar-degeneration-while-reading-aloud/. Accessed October 31, 2024.« Back to 2016 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/impaired-eye-voice-coordination-in-spinocerebellar-degeneration-while-reading-aloud/