Effects of MRI acoustic noise on resting state functional connectivity

Motivation: Loud acoustic noise during resting state fMRI can affect functional connectivity (FC), but the precise effect of MRI acoustic noise on FC is not well understood. Goal(s): To clarify the impact of MRI acoustic noise on FC. Approach: FC in mice under MRI acoustic noise was investigated using functional ultrasound (fUS), a functional imaging method based on relative cerebral blood volume, and the FC obtained was compared with FC by fMRI. Results: As acoustic noise increased, in the auditory network FC between the retrosplenial dysgranular and auditory cortexes decreased, while in the non-auditory network FC anticorrelation between the infralimbic and motor cortexes increased. Impact: Anticorrelation between the default mode network (e.g., infralimbic cortex) and task-positive networks (e.g., motor cortex) is an important feature of brain network antagonism. Attention should be paid to the acoustic noise level when fMRI to evaluate anticorrelation of such networks.