Ketamine acutely reduces global brain connectivity of the prefrontal cortex
The TD-fNIRS system used in this study provides whole head coverage and is thus well-suited to study patterns of cortical connectivity and their acute changes following ketamine administration. Existing fMRI studies focusing on ketamine-induced acute connectivity changes in healthy volunteers found an increase in brain connectivityTo calculate functional connectivity, TD-fNIRS data (i.e. HbO and HbR time-series) underwent further preprocessing (“Cortical functional connectivity derived from TD-fNIRS and its acute changes after ketamine vs. saline administration. (We started by assessing GBC, a graph-theory inspired metric (a.k.a. weighted degree centrality), which summarizes the connectivity strength of each node of the connectivity matrix