کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
6025090 1580889 2015 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Predictions to motion stimuli in human early visual cortex: Effects of motion displacement on motion predictability
ترجمه فارسی عنوان
پیش بینی های محرک حرکت در قشر انسانی اولیه انسان: تاثیر حرکت جابجایی بر پیش بینی حرکت
موضوعات مرتبط
علوم زیستی و بیوفناوری علم عصب شناسی علوم اعصاب شناختی
چکیده انگلیسی
Recently, several studies showed that fMRI BOLD responses to moving random dot stimuli are enhanced at the location of dot appearance, i.e., the motion trailing edge. Possibly, BOLD activity in human visual cortex reflects predictability of visual motion input. In the current study, we investigate to what extent fMRI BOLD responses reflect estimated predictions to visual motion. We varied motion displacement parameters (duration and velocity), while measuring BOLD amplitudes as a function of distance from the trailing edge. We have found that for all stimulus configurations, BOLD signals decrease with increasing distance from the trailing edge. This finding indicates that neural activity directly reflects the predictability of moving dots, rather than their appearance within classical receptive fields. However, different motion displacement parameters exerted only marginal effects on predictability, suggesting that early visual cortex does not literally predict motion trajectories. Rather, the results reveal a heuristic mechanism of motion suppression from trailing to leading edge, plausibly mediated through short-range horizontal connections. Simple heuristic suppression allows the visual system to recognize novel input among many motion signals, while being most energy efficient.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: NeuroImage - Volume 118, September 2015, Pages 118-125
نویسندگان
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