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Neurodevelopment for syntactic processing distinguishes childhood stuttering recovery versus persistence.

Usler E, Weber-Fox C - J Neurodev Disord (2015)

Bottom Line: During the comprehension of English sentences, ERP activity mediating semantic and syntactic (phrase structure) processing did not distinguish CWS-Per, CWS-Rec, and CWNS.However, identical phrase structure violations within Jabberwocky sentences elicited a P600 in CWNS and CWS-Rec, but an N400-like effect in CWS-Per.Unlike CWS-Rec and CWNS, the lack of semantic context in Jabberwocky sentences seemed to affect the syntactic processing strategies of CWS-Per, resulting in the elicitation of semantically based N400-like activity during syntactic (phrase structure) violations.

View Article: PubMed Central - PubMed

Affiliation: Department of Speech, Language, and Hearing Sciences, Purdue University, Lyles-Porter Hall, 715 Clinic Drive, West Lafayette, IN 47907 USA.

ABSTRACT

Background: Characterized by the presence of involuntary speech disfluencies, developmental stuttering is a neurodevelopmental disorder of atypical speech-motor coordination. Although the etiology of stuttering is multifactorial, language development during early childhood may influence both the onset of the disorder and the likelihood of recovery. The purpose of this study was to determine whether differences in neural indices mediating language processing are associated with persistence or recovery in school-age children who stutter.

Methods: Event-related brain potentials (ERPs) were obtained from 31 6-7-year-olds, including nine children who do not stutter (CWNS), 11 children who had recovered from stuttering (CWS-Rec), and 11 children who persisted in stuttering (CWS-Per), matched for age, and all with similar socioeconomic status, nonverbal intelligence, and language ability. We examined ERPs elicited by semantic and syntactic (phrase structure) violations within an auditory narrative consisting of English and Jabberwocky sentences. In Jabberwocky sentences, content words were replaced with pseudowords to limit semantic context. A mixed effects repeated measures analysis of variance (ANOVA) was computed for ERP components with four within-subject factors, including condition, hemisphere, anterior/posterior distribution, and laterality.

Results: During the comprehension of English sentences, ERP activity mediating semantic and syntactic (phrase structure) processing did not distinguish CWS-Per, CWS-Rec, and CWNS. Semantic violations elicited a qualitatively similar N400 component across groups. Phrase structure violations within English sentences also elicited a similar P600 component in all groups. However, identical phrase structure violations within Jabberwocky sentences elicited a P600 in CWNS and CWS-Rec, but an N400-like effect in CWS-Per.

Conclusions: The distinguishing neural patterns mediating syntactic, but not semantic, processing provide evidence that specific brain functions for some aspects of language processing may be associated with stuttering persistence. Unlike CWS-Rec and CWNS, the lack of semantic context in Jabberwocky sentences seemed to affect the syntactic processing strategies of CWS-Per, resulting in the elicitation of semantically based N400-like activity during syntactic (phrase structure) violations. This vulnerability suggests neural mechanisms associated with the processing of syntactic structure may be less mature in 6-7-year-old children whose stuttering persisted compared to their fluent or recovered peers.

No MeSH data available.


Related in: MedlinePlus

Grand average ERPs elicited by the syntactic condition within Jabberwocky sentences. ERPs of all participants in the CWNS, CWS-Rec, and CWS-Per groups, showing waveforms elicited in the Jabberwocky syntactic canonical (black) and violation (red) conditions.
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Fig3: Grand average ERPs elicited by the syntactic condition within Jabberwocky sentences. ERPs of all participants in the CWNS, CWS-Rec, and CWS-Per groups, showing waveforms elicited in the Jabberwocky syntactic canonical (black) and violation (red) conditions.

Mentions: In order to measure individual ERP components, temporal windows were selected by centering the temporal windows on the peaks of each component in the grand averages and consistent with an earlier ERP study of semantic and syntactic processing in CWS by Weber-Fox et al. [18]. In the semantic condition, mean amplitude and peak latency of N400 were measured using a 450–750-ms temporal window. For the phrase structure condition, windows of 150–300 and 600–900 ms were used to measure syntactic negativities in English and Jabberwocky. P600 mean amplitudes were measured using a temporal window of 1,000–1,300 ms for English sentences and a 1,200–1,500-ms window for Jabberwocky sentences. The later temporal window for Jabberwocky compared to that for English was based on the previous finding that the elicitation of the P600 for processing syntactic violations within Jabberwocky is attenuated compared to the P600 elicited by identical violations within English [54]. For display purposes, the ERP waveforms shown in Figures 1, 2, and 3 were low-pass filtered at 20 Hz.Figure 1


Neurodevelopment for syntactic processing distinguishes childhood stuttering recovery versus persistence.

Usler E, Weber-Fox C - J Neurodev Disord (2015)

Grand average ERPs elicited by the syntactic condition within Jabberwocky sentences. ERPs of all participants in the CWNS, CWS-Rec, and CWS-Per groups, showing waveforms elicited in the Jabberwocky syntactic canonical (black) and violation (red) conditions.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4318174&req=5

Fig3: Grand average ERPs elicited by the syntactic condition within Jabberwocky sentences. ERPs of all participants in the CWNS, CWS-Rec, and CWS-Per groups, showing waveforms elicited in the Jabberwocky syntactic canonical (black) and violation (red) conditions.
Mentions: In order to measure individual ERP components, temporal windows were selected by centering the temporal windows on the peaks of each component in the grand averages and consistent with an earlier ERP study of semantic and syntactic processing in CWS by Weber-Fox et al. [18]. In the semantic condition, mean amplitude and peak latency of N400 were measured using a 450–750-ms temporal window. For the phrase structure condition, windows of 150–300 and 600–900 ms were used to measure syntactic negativities in English and Jabberwocky. P600 mean amplitudes were measured using a temporal window of 1,000–1,300 ms for English sentences and a 1,200–1,500-ms window for Jabberwocky sentences. The later temporal window for Jabberwocky compared to that for English was based on the previous finding that the elicitation of the P600 for processing syntactic violations within Jabberwocky is attenuated compared to the P600 elicited by identical violations within English [54]. For display purposes, the ERP waveforms shown in Figures 1, 2, and 3 were low-pass filtered at 20 Hz.Figure 1

Bottom Line: During the comprehension of English sentences, ERP activity mediating semantic and syntactic (phrase structure) processing did not distinguish CWS-Per, CWS-Rec, and CWNS.However, identical phrase structure violations within Jabberwocky sentences elicited a P600 in CWNS and CWS-Rec, but an N400-like effect in CWS-Per.Unlike CWS-Rec and CWNS, the lack of semantic context in Jabberwocky sentences seemed to affect the syntactic processing strategies of CWS-Per, resulting in the elicitation of semantically based N400-like activity during syntactic (phrase structure) violations.

View Article: PubMed Central - PubMed

Affiliation: Department of Speech, Language, and Hearing Sciences, Purdue University, Lyles-Porter Hall, 715 Clinic Drive, West Lafayette, IN 47907 USA.

ABSTRACT

Background: Characterized by the presence of involuntary speech disfluencies, developmental stuttering is a neurodevelopmental disorder of atypical speech-motor coordination. Although the etiology of stuttering is multifactorial, language development during early childhood may influence both the onset of the disorder and the likelihood of recovery. The purpose of this study was to determine whether differences in neural indices mediating language processing are associated with persistence or recovery in school-age children who stutter.

Methods: Event-related brain potentials (ERPs) were obtained from 31 6-7-year-olds, including nine children who do not stutter (CWNS), 11 children who had recovered from stuttering (CWS-Rec), and 11 children who persisted in stuttering (CWS-Per), matched for age, and all with similar socioeconomic status, nonverbal intelligence, and language ability. We examined ERPs elicited by semantic and syntactic (phrase structure) violations within an auditory narrative consisting of English and Jabberwocky sentences. In Jabberwocky sentences, content words were replaced with pseudowords to limit semantic context. A mixed effects repeated measures analysis of variance (ANOVA) was computed for ERP components with four within-subject factors, including condition, hemisphere, anterior/posterior distribution, and laterality.

Results: During the comprehension of English sentences, ERP activity mediating semantic and syntactic (phrase structure) processing did not distinguish CWS-Per, CWS-Rec, and CWNS. Semantic violations elicited a qualitatively similar N400 component across groups. Phrase structure violations within English sentences also elicited a similar P600 component in all groups. However, identical phrase structure violations within Jabberwocky sentences elicited a P600 in CWNS and CWS-Rec, but an N400-like effect in CWS-Per.

Conclusions: The distinguishing neural patterns mediating syntactic, but not semantic, processing provide evidence that specific brain functions for some aspects of language processing may be associated with stuttering persistence. Unlike CWS-Rec and CWNS, the lack of semantic context in Jabberwocky sentences seemed to affect the syntactic processing strategies of CWS-Per, resulting in the elicitation of semantically based N400-like activity during syntactic (phrase structure) violations. This vulnerability suggests neural mechanisms associated with the processing of syntactic structure may be less mature in 6-7-year-old children whose stuttering persisted compared to their fluent or recovered peers.

No MeSH data available.


Related in: MedlinePlus