Limits...
Multisensory and modality specific processing of visual speech in different regions of the premotor cortex.

Callan DE, Jones JA, Callan A - Front Psychol (2014)

Bottom Line: The left inferior parietal lobule and right cerebellum also showed these properties.The left ventral superior and dorsal premotor cortex (PMvs/PMd) did not show this multisensory enhancement effect, but there was greater activity for the visual only over audio-visual conditions in these areas.The results suggest that the inferior regions of the ventral premotor cortex are involved with integrating multisensory information, whereas, more superior and dorsal regions of the PMC are involved with mapping unimodal (in this case visual) sensory features of the speech signal with articulatory speech gestures.

View Article: PubMed Central - PubMed

Affiliation: Center for Information and Neural Networks, National Institute of Information and Communications Technology, Osaka University Osaka, Japan ; Multisensory Cognition and Computation Laboratory Universal Communication Research Institute, National Institute of Information and Communications Technology Kyoto, Japan.

ABSTRACT
Behavioral and neuroimaging studies have demonstrated that brain regions involved with speech production also support speech perception, especially under degraded conditions. The premotor cortex (PMC) has been shown to be active during both observation and execution of action ("Mirror System" properties), and may facilitate speech perception by mapping unimodal and multimodal sensory features onto articulatory speech gestures. For this functional magnetic resonance imaging (fMRI) study, participants identified vowels produced by a speaker in audio-visual (saw the speaker's articulating face and heard her voice), visual only (only saw the speaker's articulating face), and audio only (only heard the speaker's voice) conditions with varying audio signal-to-noise ratios in order to determine the regions of the PMC involved with multisensory and modality specific processing of visual speech gestures. The task was designed so that identification could be made with a high level of accuracy from visual only stimuli to control for task difficulty and differences in intelligibility. The results of the functional magnetic resonance imaging (fMRI) analysis for visual only and audio-visual conditions showed overlapping activity in inferior frontal gyrus and PMC. The left ventral inferior premotor cortex (PMvi) showed properties of multimodal (audio-visual) enhancement with a degraded auditory signal. The left inferior parietal lobule and right cerebellum also showed these properties. The left ventral superior and dorsal premotor cortex (PMvs/PMd) did not show this multisensory enhancement effect, but there was greater activity for the visual only over audio-visual conditions in these areas. The results suggest that the inferior regions of the ventral premotor cortex are involved with integrating multisensory information, whereas, more superior and dorsal regions of the PMC are involved with mapping unimodal (in this case visual) sensory features of the speech signal with articulatory speech gestures.

No MeSH data available.


Related in: MedlinePlus

Significant brain activity for the combined AV conditions thresholded at pFDR < 0.05 corrected. Activity was present in left and right PMvi/Broca's area, left PMvs/PMd, left and right STG/S including primary and secondary auditory cortex, left MT/V5 visual motion processing area, and the right cerebellum lobule VIIb.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4017150&req=5

Figure 4: Significant brain activity for the combined AV conditions thresholded at pFDR < 0.05 corrected. Activity was present in left and right PMvi/Broca's area, left PMvs/PMd, left and right STG/S including primary and secondary auditory cortex, left MT/V5 visual motion processing area, and the right cerebellum lobule VIIb.

Mentions: The random effect results of the fMRI analyses of the contrasts of interest are given in Figures 3–8 and Tables 3–7. The brain activity rendered on the surface of the brain for the contrast of VO relative to baseline (still face plus button press) is given in Figure 3. Significant activity (pFDR < 0.05 corrected across entire volume; T = 4.38; see Table 3 for detailed results) was present in left PMvi/Broca's area, left PMvs/PMd, left and right middle temporal visual motion processing area (MT/V5). The results of the ROI analysis showed significant activity (p < 0.05 corrected; see Table 3) in the left PMvi/Brocas area (MNI coordinate: −48, 9, 12), the left PMvs/PMd (MNI coordinate: −39, 3, 54). Significant activity (pFDR < 0.05 corrected across entire volume; T = 3.28) for the combined AV conditions was present in left and right PMvi/Broca's area, left PMvs/PMd, left and right STG/S, left MT/V5, and right cerebellum lobule VIIb (see Figure 4 and Table 4). The results of the ROI analysis showed significant activity (p < 0.05 corrected; see Table 4) in the left PMvi/Broca's area (MNI coordinate: −51, 9, 9), the left PMvs/PMd (MNI coordinate: −48, 3, 42) and the right cerebellum lobule VIIb (MNI coordinate: 18, −72, −48). The conjunction of brain activity found to be active for both the combined AV conditions and the VO condition included the left PMvi/Broca's area, PMvs/PMd, and the left MT/V5 region (see Figure 5).


Multisensory and modality specific processing of visual speech in different regions of the premotor cortex.

Callan DE, Jones JA, Callan A - Front Psychol (2014)

Significant brain activity for the combined AV conditions thresholded at pFDR < 0.05 corrected. Activity was present in left and right PMvi/Broca's area, left PMvs/PMd, left and right STG/S including primary and secondary auditory cortex, left MT/V5 visual motion processing area, and the right cerebellum lobule VIIb.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4017150&req=5

Figure 4: Significant brain activity for the combined AV conditions thresholded at pFDR < 0.05 corrected. Activity was present in left and right PMvi/Broca's area, left PMvs/PMd, left and right STG/S including primary and secondary auditory cortex, left MT/V5 visual motion processing area, and the right cerebellum lobule VIIb.
Mentions: The random effect results of the fMRI analyses of the contrasts of interest are given in Figures 3–8 and Tables 3–7. The brain activity rendered on the surface of the brain for the contrast of VO relative to baseline (still face plus button press) is given in Figure 3. Significant activity (pFDR < 0.05 corrected across entire volume; T = 4.38; see Table 3 for detailed results) was present in left PMvi/Broca's area, left PMvs/PMd, left and right middle temporal visual motion processing area (MT/V5). The results of the ROI analysis showed significant activity (p < 0.05 corrected; see Table 3) in the left PMvi/Brocas area (MNI coordinate: −48, 9, 12), the left PMvs/PMd (MNI coordinate: −39, 3, 54). Significant activity (pFDR < 0.05 corrected across entire volume; T = 3.28) for the combined AV conditions was present in left and right PMvi/Broca's area, left PMvs/PMd, left and right STG/S, left MT/V5, and right cerebellum lobule VIIb (see Figure 4 and Table 4). The results of the ROI analysis showed significant activity (p < 0.05 corrected; see Table 4) in the left PMvi/Broca's area (MNI coordinate: −51, 9, 9), the left PMvs/PMd (MNI coordinate: −48, 3, 42) and the right cerebellum lobule VIIb (MNI coordinate: 18, −72, −48). The conjunction of brain activity found to be active for both the combined AV conditions and the VO condition included the left PMvi/Broca's area, PMvs/PMd, and the left MT/V5 region (see Figure 5).

Bottom Line: The left inferior parietal lobule and right cerebellum also showed these properties.The left ventral superior and dorsal premotor cortex (PMvs/PMd) did not show this multisensory enhancement effect, but there was greater activity for the visual only over audio-visual conditions in these areas.The results suggest that the inferior regions of the ventral premotor cortex are involved with integrating multisensory information, whereas, more superior and dorsal regions of the PMC are involved with mapping unimodal (in this case visual) sensory features of the speech signal with articulatory speech gestures.

View Article: PubMed Central - PubMed

Affiliation: Center for Information and Neural Networks, National Institute of Information and Communications Technology, Osaka University Osaka, Japan ; Multisensory Cognition and Computation Laboratory Universal Communication Research Institute, National Institute of Information and Communications Technology Kyoto, Japan.

ABSTRACT
Behavioral and neuroimaging studies have demonstrated that brain regions involved with speech production also support speech perception, especially under degraded conditions. The premotor cortex (PMC) has been shown to be active during both observation and execution of action ("Mirror System" properties), and may facilitate speech perception by mapping unimodal and multimodal sensory features onto articulatory speech gestures. For this functional magnetic resonance imaging (fMRI) study, participants identified vowels produced by a speaker in audio-visual (saw the speaker's articulating face and heard her voice), visual only (only saw the speaker's articulating face), and audio only (only heard the speaker's voice) conditions with varying audio signal-to-noise ratios in order to determine the regions of the PMC involved with multisensory and modality specific processing of visual speech gestures. The task was designed so that identification could be made with a high level of accuracy from visual only stimuli to control for task difficulty and differences in intelligibility. The results of the functional magnetic resonance imaging (fMRI) analysis for visual only and audio-visual conditions showed overlapping activity in inferior frontal gyrus and PMC. The left ventral inferior premotor cortex (PMvi) showed properties of multimodal (audio-visual) enhancement with a degraded auditory signal. The left inferior parietal lobule and right cerebellum also showed these properties. The left ventral superior and dorsal premotor cortex (PMvs/PMd) did not show this multisensory enhancement effect, but there was greater activity for the visual only over audio-visual conditions in these areas. The results suggest that the inferior regions of the ventral premotor cortex are involved with integrating multisensory information, whereas, more superior and dorsal regions of the PMC are involved with mapping unimodal (in this case visual) sensory features of the speech signal with articulatory speech gestures.

No MeSH data available.


Related in: MedlinePlus