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Network Modeling for Functional Magnetic Resonance Imaging (fMRI) Signals during Ultra-Fast Speech Comprehension in Late-Blind Listeners.

Dietrich S, Hertrich I, Ackermann H - PLoS ONE (2015)

Bottom Line: Regarding the output V1 was significantly connected to pre-SMA in blind individuals, and the strength of V1-SMA connectivity correlated with the performance of ultra-fast speech comprehension.By contrast, in sighted controls, not understanding ultra-fast speech, pre-SMA did neither receive input from A1 nor V1.Taken together, right V1 might facilitate the "parsing" of the ultra-fast speech stream in blind subjects by receiving subcortical auditory input via the Pv (= secondary visual pathway) and transmitting this information toward contralateral pre-SMA.

View Article: PubMed Central - PubMed

Affiliation: Department of General Neurology, Hertie Institute for Clinical Brain Research, Center for Neurology, University of Tübingen, Hoppe-Seyler-Str. 3, D-72076 Tübingen, Germany.

ABSTRACT
In many functional magnetic resonance imaging (fMRI) studies blind humans were found to show cross-modal reorganization engaging the visual system in non-visual tasks. For example, blind people can manage to understand (synthetic) spoken language at very high speaking rates up to ca. 20 syllables/s (syl/s). FMRI data showed that hemodynamic activation within right-hemispheric primary visual cortex (V1), bilateral pulvinar (Pv), and left-hemispheric supplementary motor area (pre-SMA) covaried with their capability of ultra-fast speech (16 syllables/s) comprehension. It has been suggested that right V1 plays an important role with respect to the perception of ultra-fast speech features, particularly the detection of syllable onsets. Furthermore, left pre-SMA seems to be an interface between these syllabic representations and the frontal speech processing and working memory network. So far, little is known about the networks linking V1 to Pv, auditory cortex (A1), and (mesio-) frontal areas. Dynamic causal modeling (DCM) was applied to investigate (i) the input structure from A1 and Pv toward right V1 and (ii) output from right V1 and A1 to left pre-SMA. As concerns the input Pv was significantly connected to V1, in addition to A1, in blind participants, but not in sighted controls. Regarding the output V1 was significantly connected to pre-SMA in blind individuals, and the strength of V1-SMA connectivity correlated with the performance of ultra-fast speech comprehension. By contrast, in sighted controls, not understanding ultra-fast speech, pre-SMA did neither receive input from A1 nor V1. Taken together, right V1 might facilitate the "parsing" of the ultra-fast speech stream in blind subjects by receiving subcortical auditory input via the Pv (= secondary visual pathway) and transmitting this information toward contralateral pre-SMA.

No MeSH data available.


Related in: MedlinePlus

Correlation between DCM parameter and performance of ultra-fast speech comprehension.Connection strength of V1-pre-SMA (unfilled squares) and driving input on Pv (filled diamonds) plotted against individual behavioral performance of ultra-fast speech comprehension of the blind subgroup. Regression lines, correlation coefficients (Spearman Rho), and significance level were given.
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pone.0132196.g006: Correlation between DCM parameter and performance of ultra-fast speech comprehension.Connection strength of V1-pre-SMA (unfilled squares) and driving input on Pv (filled diamonds) plotted against individual behavioral performance of ultra-fast speech comprehension of the blind subgroup. Regression lines, correlation coefficients (Spearman Rho), and significance level were given.

Mentions: A significant positive correlation between DCM parameters of the blind subgroup and behavioral performance of ultra-fast speech comprehension was expected and could be found regarding (i) connectivity from V1 to pre-SMA (two-tailed Spearman test; ρ = 0.636, p < 0.05, uncorr., Fig 6, S2 Table) as well as (ii) driving input on Pv during the ultra-fast speech condition (two-tailed Spearman test; fw16: ρ = 0.764, p < 0.01, corr., Fig 6, S2 Table). Additionally, not significant, but tentative, parameters of Pv-V1 connection were found to be correlated with performance of ultra-fast speech comprehension of blind individuals (two-tailed Spearman test; ρ = 0.582, p = 0.06, S2 Table). Regarding correlations between DCM parameters and the age of blindness onset neither intrinsic connections nor driving input reached significance under Bonferroni Holm correction (S2 Table). As concerns sighted participants no correlation at all could be found (S2 Table).


Network Modeling for Functional Magnetic Resonance Imaging (fMRI) Signals during Ultra-Fast Speech Comprehension in Late-Blind Listeners.

Dietrich S, Hertrich I, Ackermann H - PLoS ONE (2015)

Correlation between DCM parameter and performance of ultra-fast speech comprehension.Connection strength of V1-pre-SMA (unfilled squares) and driving input on Pv (filled diamonds) plotted against individual behavioral performance of ultra-fast speech comprehension of the blind subgroup. Regression lines, correlation coefficients (Spearman Rho), and significance level were given.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4492787&req=5

pone.0132196.g006: Correlation between DCM parameter and performance of ultra-fast speech comprehension.Connection strength of V1-pre-SMA (unfilled squares) and driving input on Pv (filled diamonds) plotted against individual behavioral performance of ultra-fast speech comprehension of the blind subgroup. Regression lines, correlation coefficients (Spearman Rho), and significance level were given.
Mentions: A significant positive correlation between DCM parameters of the blind subgroup and behavioral performance of ultra-fast speech comprehension was expected and could be found regarding (i) connectivity from V1 to pre-SMA (two-tailed Spearman test; ρ = 0.636, p < 0.05, uncorr., Fig 6, S2 Table) as well as (ii) driving input on Pv during the ultra-fast speech condition (two-tailed Spearman test; fw16: ρ = 0.764, p < 0.01, corr., Fig 6, S2 Table). Additionally, not significant, but tentative, parameters of Pv-V1 connection were found to be correlated with performance of ultra-fast speech comprehension of blind individuals (two-tailed Spearman test; ρ = 0.582, p = 0.06, S2 Table). Regarding correlations between DCM parameters and the age of blindness onset neither intrinsic connections nor driving input reached significance under Bonferroni Holm correction (S2 Table). As concerns sighted participants no correlation at all could be found (S2 Table).

Bottom Line: Regarding the output V1 was significantly connected to pre-SMA in blind individuals, and the strength of V1-SMA connectivity correlated with the performance of ultra-fast speech comprehension.By contrast, in sighted controls, not understanding ultra-fast speech, pre-SMA did neither receive input from A1 nor V1.Taken together, right V1 might facilitate the "parsing" of the ultra-fast speech stream in blind subjects by receiving subcortical auditory input via the Pv (= secondary visual pathway) and transmitting this information toward contralateral pre-SMA.

View Article: PubMed Central - PubMed

Affiliation: Department of General Neurology, Hertie Institute for Clinical Brain Research, Center for Neurology, University of Tübingen, Hoppe-Seyler-Str. 3, D-72076 Tübingen, Germany.

ABSTRACT
In many functional magnetic resonance imaging (fMRI) studies blind humans were found to show cross-modal reorganization engaging the visual system in non-visual tasks. For example, blind people can manage to understand (synthetic) spoken language at very high speaking rates up to ca. 20 syllables/s (syl/s). FMRI data showed that hemodynamic activation within right-hemispheric primary visual cortex (V1), bilateral pulvinar (Pv), and left-hemispheric supplementary motor area (pre-SMA) covaried with their capability of ultra-fast speech (16 syllables/s) comprehension. It has been suggested that right V1 plays an important role with respect to the perception of ultra-fast speech features, particularly the detection of syllable onsets. Furthermore, left pre-SMA seems to be an interface between these syllabic representations and the frontal speech processing and working memory network. So far, little is known about the networks linking V1 to Pv, auditory cortex (A1), and (mesio-) frontal areas. Dynamic causal modeling (DCM) was applied to investigate (i) the input structure from A1 and Pv toward right V1 and (ii) output from right V1 and A1 to left pre-SMA. As concerns the input Pv was significantly connected to V1, in addition to A1, in blind participants, but not in sighted controls. Regarding the output V1 was significantly connected to pre-SMA in blind individuals, and the strength of V1-SMA connectivity correlated with the performance of ultra-fast speech comprehension. By contrast, in sighted controls, not understanding ultra-fast speech, pre-SMA did neither receive input from A1 nor V1. Taken together, right V1 might facilitate the "parsing" of the ultra-fast speech stream in blind subjects by receiving subcortical auditory input via the Pv (= secondary visual pathway) and transmitting this information toward contralateral pre-SMA.

No MeSH data available.


Related in: MedlinePlus