Question/statement judgments: an fMRI study of intonation processing

Abstract

We examined changes in fMRI BOLD signal associated with question/statement judgments in an event-related paradigm to investigate the neural basis of processing one aspect of intonation. Subjects made judgments about digitized recordings of three types of utterances: questions with rising intonation (RQ; e.g., "She was talking to her father?"), statements with a falling intonation (FS; e.g., "She was talking to her father."), and questions with a falling intonation and a word order change (FQ; e.g., "Was she talking to her father?"). Functional echo planar imaging (EPI) scans were collected from 11 normal subjects. There was increased BOLD activity in bilateral inferior frontal and temporal regions for RQ over either FQ or FS stimuli. The study provides data relevant to the location of regions responsive to intonationally marked illocutionary differences between questions and statements.

Figure 1

Three paired stimuli illustrating the different intonation conditions in the experiment. The data set consists of voice spectrographs with uncorrected fundamental frequency (pitch) contours superimposed as a dark black line. From top to bottom: an RQ (Rising Question) utterance (She was serving up the meal?), an FS (Falling Statement) utterance (She was serving up the meal), and an FQ (Falling Question) utterance (Was she serving up the meal). (Figure created using PRAAT software.)

Figure 2

Schematic map of the 17 regions of interest defined on the averaged folding patterns of the cortical surface. The lateral surface of the left hemisphere is depicted in the top view and the ventral surface is depicted in the bottom view. Light gray areas represent gyri. Dark gray areas represent sulci. (1) superior temporal gyrus, (2) superior temporal sulcus, (3) Heschl's gyrus, (4) Sylvian fissure, (5) middle temporal gyrus, (6) inferior temporal gyrus, (7) inferior temporal sulcus, (8) temporal pole, (9) insula, (10) circular sulcus of insula, (11) inferior frontal gyrus‐pars orbitalis, (12) inferior frontal gyrus‐pars triangularis, (13) inferior frontal gyrus‐pars opercularis, (14) inferior frontal sulcus, (15) supramarginal gyrus, (16) angular gyrus, (17) precentral gyrus.

Figure 3

Statistical activation maps of the group averaged data superimposed upon a map of the averaged folding patterns of the cortical surface for the following contrasts: (A) all conditions versus white noise, (B) RQ versus FS, (C) FQ versus FS, and (D) RQ versus FQ. The corrected threshold for significance (the likelihood of getting one or more clusters of at least 300 mm² under the null hypothesis) equals P < 0.05. The scale bar indicates the P value (log 10) at each voxel.

Figure 4

Bar graphs of the mean percentage change [and standard error (SE)] in BOLD signal in the nine regions of interest where significant differences between the conditions were found. IFG = inferior frontal gyrus.