Coherence spectra between the medial prefrontal cortex and posterior cingulate cortex. Coherence at rest (upper row) and coherence difference between the resting and at-task (lower row) states for the control (left) and schizophrenia (right) groups. In the coherence spectra (upper row), the confidence level (p = 0.01) is drawn as a red line. Significant differences between the control and schizophrenia groups are marked with small green bars in the schizophrenia graph (upper right). In the coherence difference spectra (lower row), significant differences between the resting and at-task conditions are marked with small red bars.