Loading...
Search for:
mesencephalon
0.005 seconds
Speed/accuracy trade-off between the habitual and the goal-directed processes
, Article PLoS Computational Biology ; Volume 7, Issue 5 , 2011 ; 1553734X (ISSN) ; Dezfouli, A ; Piray, P ; Sharif University of Technology
2011
Abstract
Instrumental responses are hypothesized to be of two kinds: habitual and goal-directed, mediated by the sensorimotor and the associative cortico-basal ganglia circuits, respectively. The existence of the two heterogeneous associative learning mechanisms can be hypothesized to arise from the comparative advantages that they have at different stages of learning. In this paper, we assume that the goal-directed system is behaviourally flexible, but slow in choice selection. The habitual system, in contrast, is fast in responding, but inflexible in adapting its behavioural strategy to new conditions. Based on these assumptions and using the computational theory of reinforcement learning, we...
Channelopathy-related SCN10A gene variants predict cerebellar dysfunction in multiple sclerosis
, Article Neurology ; Volume 86, Issue 5 , 2016 , Pages 410-417 ; 00283878 (ISSN) ; Sadaghiani, S ; Park, M. T. M ; Mashhadi, R ; Nazeri, A ; Noshad, S ; Salehi, M. J ; Naghibzadeh, M ; Moghadasi, A. N ; Owji, M ; Doosti, R ; Hashemi Taheri, A. P ; Rad, A. S ; Azimi, A ; Chakravarty, M. M ; Voineskos, A. N ; Nazeri, A ; Sahraian, M. A ; Sharif University of Technology
Lippincott Williams and Wilkins
Abstract
Objective: To determine the motor-behavioral and neural correlates of putative functional common variants in the sodium-channel NaV1.8 encoding gene (SCN10A) in vivo in patients with multiple sclerosis (MS). Methods: We recruited 161 patients with relapsing-onset MS and 94 demographically comparable healthy participants. All patients with MS underwent structural MRI and clinical examinations (Expanded Disability Status Scale [EDSS] and Multiple Sclerosis Functional Composite [MSFC]). Whole-brain voxel-wise and cerebellar volumetry were performed to assess differences in regional brain volumes between genotype groups. Resting-state fMRI was acquired from 62 patients with MS to evaluate...