Understanding multivariate brain activity: Evaluating the effect of voxelwise noise correlations on population codes in functional magnetic resonance imaging
Fig 10
Simulation of voxel population responses based2 on realistic fMRI data.
A. noise correlation as an exponential function of signal correlation. The magenta curve is estimated from van Bergen and Jehee [22] and we scale it to increase the magnitude of noise correlations (i.e., the blue curve). B,C. simulated effects of noise correlations in the regimes of the magenta and the blue curves, respectively. Noise correlations reduce the amount of information because the overall magnitude is relatively week (i.e., the magenta curve). We again observe U-shaped functions if the overall magnitude of noise correlations are large (i.e., the blue curve).