Schizophrenia is a complex psychiatric disorder that has eluded a characterization in terms
of local abnormalities of brain activity, and is hypothesized to affect the collective,``emergent
working of the brain. We propose a novel data-driven approach to capture emergent
features using functional brain networks [Eguiluzet al] extracted from fMRI data, and
demonstrate its advantage over traditional region-of-interest (ROI) and local, task-specific
linear activation analyzes. Our results suggest that schizophrenia is indeed associated with …

Given the time-series for stimulus s (t)(eg, s= 1 if the stimulus/event is present, and s= 0
otherwise), and the BOLD signal intensity time-series vi (t) for voxel i, General Linear Model
(GLM) 1 is simply a linear regression vi (t)= βi∗ ˆs (t)+ bi+ ϵ, where ˆs (t)= HRF (t) gs (t) is the
regressor corresponding to the stimulus convolved with the hemodynamic response function
(HRF) in order to account for delay between the voxel activation and change in the BOLD
signal, ϵ is noise, b is the baseline (mean intensity) and βi coefficient is the amplitude that …