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Reduction of negative afterimage duration in Parkinson's disease patients: a possible role for dopaminergic
Fatemeh Khadjevand1, Sohrab Shahzadi, Abdolhossein Abbassian
1School of Cognitive Sciences (SCS), Institute for Research in Fundamental Sciences (IPM), Tehran 19395-5746, Iran. m.khadjvand@gmail.com
Abstract:
Dopaminergic deficiency may affect Parkinson's disease patients (PD) in the central as well as the peripheral tissues. In the retina, the neuromodulatory role of the dopaminergic Interplexiform cell layer (IP) plays a major role in the retinal light adaptation and may account for the duration of the negative afterimage. Here we present results showing a significant reduction of negative afterimage duration in PD patients. This supports the hypothesis that the retinal dopaminergic system may be the main cause for the long duration of negative afterimage. We suggest that the observed reduction of afterimage duration is due to possible dopaminergic deficiency in patients with Parkinson's disease.
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