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Broca's area, sentence comprehension, and working memory: an fMRI Study.

Rogalsky C, Matchin W, Hickok G - Front Hum Neurosci (2008)

Bottom Line: A second experiment used fMRI to document the brain regions underlying this effect.However, during concurrent speech articulation (but not finger-tapping) this complexity effect was eliminated in the pars opercularis suggesting that this region supports sentence comprehension via its role in articulatory rehearsal.Activity in the pars triangularis was modulated by the finger-tapping task, but not the speech articulation task.

View Article: PubMed Central - PubMed

Affiliation: Center for Cognitive Neuroscience & Department of Cognitive Sciences, University of California Irvine, USA.

ABSTRACT
The role of Broca's area in sentence processing remains controversial. According to one view, Broca's area is involved in processing a subcomponent of syntactic processing. Another view holds that it contributes to sentence processing via verbal working memory. Sub-regions of Broca's area have been identified that are more active during the processing of complex (object-relative clause) sentences compared to simple (subject-relative clause) sentences. The present study aimed to determine if this complexity effect can be accounted for in terms of the articulatory rehearsal component of verbal working memory. In a behavioral experiment, subjects were asked to comprehend sentences during concurrent speech articulation which minimizes articulatory rehearsal as a resource for sentence comprehension. A finger-tapping task was used as a control concurrent task. Only the object-relative clause sentences were more difficult to comprehend during speech articulation than during the manual task, showing that articulatory rehearsal does contribute to sentence processing. A second experiment used fMRI to document the brain regions underlying this effect. Subjects judged the plausibility of sentences during speech articulation, a finger-tapping task, or without a concurrent task. In the absence of a secondary task, Broca's area (pars triangularis and pars opercularis) demonstrated an increase in activity as a function of syntactic complexity. However, during concurrent speech articulation (but not finger-tapping) this complexity effect was eliminated in the pars opercularis suggesting that this region supports sentence comprehension via its role in articulatory rehearsal. Activity in the pars triangularis was modulated by the finger-tapping task, but not the speech articulation task.

No MeSH data available.


Related in: MedlinePlus

Mean comprehension performance as a function of sentence type and concurrent task. Note that during each concurrent task, 10 of each sentence type were presented. Error bars represent 95% confidence intervals.
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Figure 2: Mean comprehension performance as a function of sentence type and concurrent task. Note that during each concurrent task, 10 of each sentence type were presented. Error bars represent 95% confidence intervals.

Mentions: A 2 × 4 repeated measures ANOVA was calculated to compare the number of comprehension errors during articulation and during the finger-tapping sequence task for the four sentence types. (All but two errors (i.e. 99.5% of errors) made by all subjects involved selecting pictures with thematic roles reversed. All errors were included in the subsequent analyses.) Main effects for both secondary task condition (F(1,54) = 11.73, p < 0.0001) and sentence type (F(3,54) = 69.38, p < 0.0005) were found, but an interaction was also present, F(3,52) = 8.45, p < 0.0001. Paired sample t-tests revealed that the interaction reflects a significant difference between articulatory suppression (M = 2.96) and the finger-tapping sequence task (M = 1.95) during the comprehension of the most complex sentence type, object-relative clause sentences, t(54) = 3.96, p < 0.0001. No significant differences between suppression types were found in the active, passive, and subject-relative clause sentences (Figure 2). A significant difference between the object-relative clause sentences and each of the other sentence types, within each task condition (Table 1), also contributed to the interaction effect noted above.


Broca's area, sentence comprehension, and working memory: an fMRI Study.

Rogalsky C, Matchin W, Hickok G - Front Hum Neurosci (2008)

Mean comprehension performance as a function of sentence type and concurrent task. Note that during each concurrent task, 10 of each sentence type were presented. Error bars represent 95% confidence intervals.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2572210&req=5

Figure 2: Mean comprehension performance as a function of sentence type and concurrent task. Note that during each concurrent task, 10 of each sentence type were presented. Error bars represent 95% confidence intervals.
Mentions: A 2 × 4 repeated measures ANOVA was calculated to compare the number of comprehension errors during articulation and during the finger-tapping sequence task for the four sentence types. (All but two errors (i.e. 99.5% of errors) made by all subjects involved selecting pictures with thematic roles reversed. All errors were included in the subsequent analyses.) Main effects for both secondary task condition (F(1,54) = 11.73, p < 0.0001) and sentence type (F(3,54) = 69.38, p < 0.0005) were found, but an interaction was also present, F(3,52) = 8.45, p < 0.0001. Paired sample t-tests revealed that the interaction reflects a significant difference between articulatory suppression (M = 2.96) and the finger-tapping sequence task (M = 1.95) during the comprehension of the most complex sentence type, object-relative clause sentences, t(54) = 3.96, p < 0.0001. No significant differences between suppression types were found in the active, passive, and subject-relative clause sentences (Figure 2). A significant difference between the object-relative clause sentences and each of the other sentence types, within each task condition (Table 1), also contributed to the interaction effect noted above.

Bottom Line: A second experiment used fMRI to document the brain regions underlying this effect.However, during concurrent speech articulation (but not finger-tapping) this complexity effect was eliminated in the pars opercularis suggesting that this region supports sentence comprehension via its role in articulatory rehearsal.Activity in the pars triangularis was modulated by the finger-tapping task, but not the speech articulation task.

View Article: PubMed Central - PubMed

Affiliation: Center for Cognitive Neuroscience & Department of Cognitive Sciences, University of California Irvine, USA.

ABSTRACT
The role of Broca's area in sentence processing remains controversial. According to one view, Broca's area is involved in processing a subcomponent of syntactic processing. Another view holds that it contributes to sentence processing via verbal working memory. Sub-regions of Broca's area have been identified that are more active during the processing of complex (object-relative clause) sentences compared to simple (subject-relative clause) sentences. The present study aimed to determine if this complexity effect can be accounted for in terms of the articulatory rehearsal component of verbal working memory. In a behavioral experiment, subjects were asked to comprehend sentences during concurrent speech articulation which minimizes articulatory rehearsal as a resource for sentence comprehension. A finger-tapping task was used as a control concurrent task. Only the object-relative clause sentences were more difficult to comprehend during speech articulation than during the manual task, showing that articulatory rehearsal does contribute to sentence processing. A second experiment used fMRI to document the brain regions underlying this effect. Subjects judged the plausibility of sentences during speech articulation, a finger-tapping task, or without a concurrent task. In the absence of a secondary task, Broca's area (pars triangularis and pars opercularis) demonstrated an increase in activity as a function of syntactic complexity. However, during concurrent speech articulation (but not finger-tapping) this complexity effect was eliminated in the pars opercularis suggesting that this region supports sentence comprehension via its role in articulatory rehearsal. Activity in the pars triangularis was modulated by the finger-tapping task, but not the speech articulation task.

No MeSH data available.


Related in: MedlinePlus