TY - JOUR
T1 - Predictions to motion stimuli in human early visual cortex
T2 - Effects of motion displacement on motion predictability
AU - Schellekens, W.
AU - Ramsey, N. F.
AU - Raemaekers, M.
PY - 2015/9/1
Y1 - 2015/9/1
N2 - 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.
AB - 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.
KW - BOLD
KW - High-field fMRI
KW - Horizontal connections
KW - Motion bias
KW - Motion displacement
KW - Predictive coding
KW - Suppression
KW - Visual cortex
UR - http://www.scopus.com/inward/record.url?scp=84937574832&partnerID=8YFLogxK
U2 - 10.1016/j.neuroimage.2015.05.053
DO - 10.1016/j.neuroimage.2015.05.053
M3 - Article
C2 - 26026815
AN - SCOPUS:84937574832
SN - 1053-8119
VL - 118
SP - 118
EP - 125
JO - NeuroImage
JF - NeuroImage
ER -