Fig 1 A: In the normal control subject, coronal statistical map showing bilateral blood oxygenation level dependent (BOLD) signal increases in auditory cortex while subject was listening to external speech (subtraction of brain activity associated with listening to the noise produced by the functional magnetic resonance imaging [fMRI] machine from that associated with listening to an external speech and the noise of the fMRI machine).
B: Absence of activation in the auditory cortex and in the inferior frontal lobe when the brain activity associated with listening to external speech and the noise produced by fMRI machine was subtracted from that associated with listening to the fMRI machine alone.
C–F: In patient DT, the subtraction of brain activity associated with listening to external speech and fMRI machine noise from that associated with experiencing auditory verbal hallucinations (AVHs) and fMRI machine noise revealed a significant activation of the left superior temporal gyrus (primary auditory cortex, Brodmann’s area 41) (C) and the right middle temporal gyrus (auditory association cortex, Brodmann’s area 21) (E). The time courses of the BOLD signal increases for coronal statistical maps depicted in C and E are presented in D and F, respectively.
G: When the brain activity associated with experiencing an AVH and listening to the noise of the fMRI machine was subtracted from that associated with listening to external speech and the fMRI machine, there were BOLD signal increases seen in the areas of interest.