Oculomotor studies provide a novel strategy for evaluating the functional inte grity of multiple brain systems and cognitive processes in autism. The current s tudy compared pursuit eye movements of 60 highfunctioni...Oculomotor studies provide a novel strategy for evaluating the functional inte grity of multiple brain systems and cognitive processes in autism. The current s tudy compared pursuit eye movements of 60 highfunctioning individuals with aut ism and 94 intelligence quotient, age and gender matched healthy individuals usi ng ramp and oscillating target tasks. Individuals with autism had normal pursuit latency, but reduced closedloop pursuit gain when tracking both oscillating a nd ramp targets. This closedloop deficit was similar for leftward and rightwar d pursuit, but the difference between individuals with autism and their agemat ched peers was more apparent after midadolescence, suggesting reduced maturati onal achievement of the pursuit system in autism. Individuals with autism also h ad lower openloop pursuit gain (initial 100 ms of pursuit) and less accurate i nitial catchup saccades during a foveofugal stepramp task, but these deficit s were only seen when targets moved into the right visual field. Pursuit perform ance in both openand closedloop phases was correlated with manual praxis in individuals with autism. Bilateral disturbances in the ability to use internally generated extraretinal signals for closedloop pursuit implicate frontostriata l or cerebellar circuitry. The hemifield specific deficit in openloop pursuit demonstrates a lateralized disturbance in the left extrastriate areas that extra ct visual motion information, or in the transfer of visual motion information to the sensorimotor areas that transform visual information into appropriate oculo motor commands.展开更多
文摘Oculomotor studies provide a novel strategy for evaluating the functional inte grity of multiple brain systems and cognitive processes in autism. The current s tudy compared pursuit eye movements of 60 highfunctioning individuals with aut ism and 94 intelligence quotient, age and gender matched healthy individuals usi ng ramp and oscillating target tasks. Individuals with autism had normal pursuit latency, but reduced closedloop pursuit gain when tracking both oscillating a nd ramp targets. This closedloop deficit was similar for leftward and rightwar d pursuit, but the difference between individuals with autism and their agemat ched peers was more apparent after midadolescence, suggesting reduced maturati onal achievement of the pursuit system in autism. Individuals with autism also h ad lower openloop pursuit gain (initial 100 ms of pursuit) and less accurate i nitial catchup saccades during a foveofugal stepramp task, but these deficit s were only seen when targets moved into the right visual field. Pursuit perform ance in both openand closedloop phases was correlated with manual praxis in individuals with autism. Bilateral disturbances in the ability to use internally generated extraretinal signals for closedloop pursuit implicate frontostriata l or cerebellar circuitry. The hemifield specific deficit in openloop pursuit demonstrates a lateralized disturbance in the left extrastriate areas that extra ct visual motion information, or in the transfer of visual motion information to the sensorimotor areas that transform visual information into appropriate oculo motor commands.
