Imperfect (de)convolution may introduce spurious psychophysiological interactions and how to avoid it.

ABSTRACT: Psychophysiological interaction (PPI) is a widely used regression-based method to study connectivity changes in different experimental conditions. A PPI effect is generated by point-by-point multiplication of a psychological variable (experimental design) and a physiological variable (time series of a seed region). If the psychological variable is non-centered with a constant component, the constant component will add a physiological variable to the PPI term. The physiological component would in theory be accounted for by the physiological main effect in the model. But due to imperfect deconvolution and convolution with hemodynamic response function, the physiological component in PPI may no longer be exactly the same as the physiological main effect. This issue was illustrated by analyzin

SUBMITTER: Di X 

PROVIDER: S-EPMC6866926 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature