Saccadic adaptation in children.
Saccades are fast-orienting eye movements. Saccadic adaptation, a form of motor learning, is a corrective change in the amplitude of saccades in response to error. The aim of the study was to ascertain whether saccadic adaptation occurs in typically developing children. We recorded saccades with an infrared eye tracker in 39 children, aged 8 to 19 years, at baseline to 12-degree horizontal target steps and after an adaptive task. During the adaptive task, a saccadic hypometric error was induced. This task consisted of 200 12-degree target steps that stepped backward 3 degrees during the initial saccade and without the participants' awareness. The initial saccade triggered the back-step. This paradigm required a corrective reduction of the amplitude of the initial saccades in response to the induced error. Saccadic adaptation was achieved in 26 participants, whose mean saccadic amplitudes decreased by 13% (P < .05). Saccadic adaptation was not influenced by age. We conclude that children as young as 8 years old have established functions of the neural circuits responsible for the motor learning required for saccadic adaptation.
Salman
Michael S
MS
Division of Neurology, The Hospital for Sick Children, Toronto, ON, Canada.
Sharpe
James A
JA
Eizenman
Moshe
M
Lillakas
Linda
L
To
Teresa
T
Westall
Carol
C
Dennis
Maureen
M
Steinbach
Martin J
MJ
D000222:Adaptation, Physiological / Q000502:physiology*; D000293:Adolescent; D000328:Adult; D000375:Aging / Q000502:physiology; D001921:Brain / Q000254:growth & development*; D002648:Child; D005260:Female; D006801:Humans; D007858:Learning / Q000502:physiology*; D008297:Male; D009434:Neural Pathways / Q000254:growth & development*; D009483:Neuropsychological Tests; D009801:Oculomotor Muscles / Q000294:innervation / Q000502:physiology; D010775:Photic Stimulation; D012438:Saccades / Q000502:physiology*