Regional homogeneity of intrinsic brain activity correlates with auditory-motor processing of vocal pitch errors

It has been well documented that speakers produce rapid compensatory vocal adjustments for errors they perceive in their auditory feedback. The fact that they differ greatly in the degree to which they compensate for perceived errors, however, has received much less attention. The present study investigated whether intrinsic brain activity during resting can predict an individual's behavioral and cortical responses in compensating for pitch-shifted auditory feedback during vocalization. This relationship was investigated by correlating the regional homogeneity (ReHo) of resting-state fMRI signals with the vocal compensation and event-related potentials (N1 and P2) in response to pitch shifts of -200 and -500 cents. Behaviorally, the magnitudes of vocal compensation were significantly correlated with the ReHo values in the right supplementary motor area (SMA) for both -200 and -500 cents, the right primary motor cortex (M1) for -200 cents, and the left premotor cortex (PMC) for -500 cents. For both pitch shift sizes, there were significant correlations between ReHo and N1 amplitude in the left inferior frontal gyrus (IFG), right superior temporal gyrus (STG), bilateral M1, and left SMA. Significant correlations between ReHo and P2 amplitude were observed in the bilateral IFG, right STG, left SMA and M1 for -200 and -500 cents, the left PMC for -200 cents, and the right SMA for -500 cents. These findings provide the first evidence that regional homogeneity of intrinsic brain activity can predict behavioral and cortical responses in compensating for pitch errors in voice auditory feedback.