Grammatical Morpheme Effects on Sentence Processing by School-Aged Adolescents with Specific Language Impairment

Grammaticality Judgments of Tense and Agreement by Children With and Without Developmental Language Disorder Across Dialects of English

PURPOSE

Within General American English (GAE), the grammar weaknesses of children with developmental language disorder (DLD) have been documented with many tasks, including grammaticality judgments. Recently, Vaughn et al. replicated this finding with a judgment task targeting tense and agreement (T/A) structures for children who spoke African American English (AAE), a dialect that contains a greater variety of T/A forms than GAE. In the current study, we further tested this finding for children who spoke Southern White English (SWE), another dialect that contains a greater variety of T/A forms than GAE but less variety than AAE. Then, combining the SWE and AAE data, we explored the effects of a child's dialect, clinical group, and production of T/A forms on the children's judgments.

METHOD

The data were from 88 SWE-speaking children (DLD, n = 18; typically developing [TD], n = 70) and 91 AAE-speaking children (DLD, n = 34; TD, n = 57) previously studied. As in the AAE study, the SWE judgment data were examined both with A' scores and percentages of acceptability, with comparisons between dialects made on percentages of acceptability.

RESULTS

As in AAE, the SWE DLD group had significantly different A' scores and percentages of acceptability than the SWE TD group for all sentence types, including those with T/A structures. Additional analyses indicated that the judgments of the TD but not the DLD groups showed dialect effects. Except for verbal -s, overt production and grammaticality judgments were correlated for the TD but not for the DLD groups.

CONCLUSIONS

Children with DLD across dialects of English present grammar difficulties that affect their ability to make judgments about sentences. More cross-dialectal research is needed to better understand the grammatical weaknesses of childhood DLD, especially for structures such as verbal -s that are expressed differently across dialects of English.

Persistent Neurobehavioral Markers of Developmental Morphosyntax Errors in Adults

Purpose Child language acquisition is marked by an optional infinitive period (ages 2-4 years) during which children use nonfinite (infinitival) verb forms and finite verb forms interchangeably in grammatical contexts that require finite forms. In English, children's errors include omissions of past tense /-ed/ and 3rd-person singular /-s/. This language acquisition period typically ends by the age of 4 years, but it persists in children with language impairments. It is unknown if adults still process optional infinitives differently than other kinds of morphosyntax errors. Method We compared behavior and functional brain activation during grammaticality judgments across sentences with developmental optional infinitive tense/agreement errors ("Yesterday I play the song"), nondevelopmental agreement errors ("He am tall") that do not occur in typical child language acquisition, and grammatically correct sentences. Results Adults (N = 25) were significantly slower and less accurate in judging sentences with developmental errors relative to other sentences. Sentences with developmental errors yielded greater activation in bilateral inferior frontal gyri relative to nondevelopmental error sentences in both auditory and visual modalities. Conclusions These findings suggest that the heightened computational demands for finiteness extend well beyond early childhood and continue to exert their influence on grammatical mental and brain function in adulthood.

Identifying the relationship between oscillatory dynamics and event-related responses

Event related potentials (ERPs) and time frequency analysis of the EEG can identify the temporally distinct coordination of groups of neurons across brain regions during sentence processing. Although there are strong arguments that ERP components and neural oscillations are driven by the same changes in the neural signal, others argue that the lack of clear associations between the two suggests oscillatory dynamics are more than just time frequency representations of ERP components, making it unclear how the two are related. The current study seeks to examine the neural activity underlying auditory sentence processing of both semantic and syntactic errors to clarify if ERP and time frequency analyses identify the same or unique neural responses. Thirty-nine adults completed an auditory semantic judgment task and a grammaticality judgment task. As expected, the semantic judgment task elicited a larger N400 and greater increase in theta power for semantic errors compared to correct sentences and the syntactic judgment task elicited a greater P600 and beta power decrease for both grammatical error types compared to syntactically correct sentences. Importantly, we identified a significant relationship between the N400 and P600 ERPs and theta and beta oscillatory dynamics during semantic and syntactic processing. These findings suggest that ERPs and neural oscillations measure similar neural processes; however, unaccounted for variance may indicate that neural oscillations provide additional information regarding fluctuations in power within a given frequency band. Future studies that vary semantic and syntactic complexity are necessary to understand the cognitive processes that are indexed by these oscillations.

Neural patterns elicited by sentence processing uniquely characterize typical development, SLI recovery, and SLI persistence

Background

A substantial amount of work has examined language abilities in young children with specific language impairment (SLI); however, our understanding of the developmental trajectory of language impairment is limited. Along with studying the behavioral changes that occur across development, it is important to examine the neural indices of language processing for children with different language trajectories. The current study sought to examine behavioral and neural bases of language processing in adolescents showing three different trajectories: those with normal language development (NL), those exhibiting persistent SLI (SLI-Persistent), and those with a history of SLI who appear to have recovered (SLI-Recovered).

Methods

Through a sentence judgment task, we examined semantic and syntactic processing. Adolescents judged whether or not each sentence was semantically and syntactically correct. Stimuli consisted of naturally spoken sentences that were either correct, contained a semantic verb error, or contained a syntactic verb agreement error. Verb agreement errors consisted of omission and commission violations of the third-person singular -s. Behavioral button-press responses and electroencephalographic recordings were collected. Behavioral judgments and mean amplitude of the N400 and P600 components were examined.

Results

Adolescents in the SLI-Persistent group had lower sentence judgment accuracy overall, relative to the NL and SLI-Recovered groups. Accuracy in judging omission and commission syntactic errors were marginally different, with marginally lower accuracy for commission errors. All groups demonstrated an N400 component elicited by semantic violations. However, adolescents in the SLI-Persistent group demonstrated a less robust P600 component for syntactic violations. Furthermore, adolescents in the SLI-Recovered group exhibited a similar neural profile to the NL group for the semantic and syntactic omission violations. However, a unique profile with initial negativity was observed in the SLI-Recovered group in the commission violation condition.

Conclusions

Adolescents with persistent language impairment continue to demonstrate delays in language processing at the behavioral and neural levels. Conversely, the adolescents in the SLI-Recovered group appear to have made gains in language processing skills to overcome their initial impairments. However, our findings suggest that the adolescents in the SLI-Recovered group may have compensatory processing strategies for some aspects of language, as evidenced by a unique event-related potential profile.

Sentence Repetition Accuracy in Adults With Developmental Language Impairment: Interactions of Participant Capacities and Sentence Structures

PURPOSE

We asked whether sentence repetition accuracy could be explained by interactions of participant processing limitations with the structures of the sentences. We also tested a prediction of the procedural deficit hypothesis (Ullman & Pierpont, 2005) that adjuncts are more difficult than arguments for individuals with developmental language impairment (DLI).

METHOD

Forty-four young adults participated, 21 with DLI. The sentence repetition task varied sentence length and the use of arguments and adjuncts. We also administered measures of working memory and processing speed. Our regression models focused on these interactions: group and argument status; processing speed, length, and argument status; and working memory capacity, length, and argument status.

RESULTS

Language ability group was a significant predictor of sentence repetition accuracy but did not interact with argument status. Processing speed interacted with sentence length and argument status. Working memory capacity and its separate interactions with argument status and sentence length predicted sentence repetition accuracy.

CONCLUSIONS

Many adults with DLI may have difficulty with adjuncts as a result of their working memory limitations rather than their language ability. Cognitive limitations common to individuals with DLI are revealed more by particular sentence structures, suggesting ways to construct more diagnostically accurate sentence repetition tasks.

Lexical decay during online sentence processing in adults with specific language impairment

PURPOSE

Decay of memory traces is an important component of many theories of working memory, but there is conflicting evidence on whether the rate of decay differs for individuals with specific language impairment (SLI) as compared to peers with typical language. The authors tested the hypothesis that adults with SLI have a slower decay rate.

METHOD

Twenty adults with SLI, ages 18-27 years, and 23 age-matched peers identified target words in sentences. Sentences were presented at normal and slow rates. Participants separately judged whether a picture and sentence matched in meaning as a measure of sentence processing efficiency.

RESULTS

After controlling for sentence processing efficiency, the group with SLI was slower to detect words in sentences. Response times for the group with SLI increased less in the slow condition as compared to the group with typical language, resulting in a Group × Presentation Rate interaction.

CONCLUSIONS

The Group × Presentation Rate interaction is consistent with a slower lexical decay rate for adults with SLI, but differences in the ability to manage interference could not be ruled out. The findings suggest that decay rate differences may play a role in the working memory limitations found in individuals with SLI.

Production and processing of subject-verb agreement in monolingual Dutch children with specific language impairment

PURPOSE

In this study, the authors investigated whether errors with subject-verb agreement in monolingual Dutch children with specific language impairment (SLI) are influenced by verb phonology. In addition, the productive and receptive abilities of Dutch acquiring children with SLI regarding agreement inflection were compared.

METHOD

An SLI group (6-8 years old), an age-matched group with typical development, and a language-matched, younger, typically developing (TD) group participated in the study. Using an elicitation task, the authors tested use of third person singular inflection after verbs that ended in obstruents (plosive, fricative) or nonobstruents (sonorant). The authors used a self-paced listening task to test sensitivity to subject-verb agreement violations.

RESULTS

Omission was more frequent after obstruents than nonobstruents; the younger TD group used inflection less often after plosives than fricatives, unlike the SLI group. The SLI group did not detect subject-verb agreement violations if the ungrammatical structure contained a frequent error (omission), but if the ungrammatical structure contained an infrequent error (substitution), subject-verb agreement violations were noticed.

CONCLUSIONS

The use of agreement inflection by children with TD or SLI is affected by verb phonology. Differential effects in the 2 groups are consistent with a delayed development in Dutch SLI. Parallels between productive and receptive abilities point to weak lexical agreement inflection representations in Dutch SLI.

Decreased sensitivity to long-distance dependencies in children with a history of specific language impairment: electrophysiological evidence

PURPOSE

One possible source of tense and agreement limitations in children with specific language impairment (SLI) is a weakness in appreciating structural dependencies that occur in many sentences in the input. This possibility was tested in the present study.

METHOD

Children with a history of SLI (H-SLI; n = 12; M = 9;7 [years;months]) and typically developing same-age peers (TD; n = 12; M = 9;7) listened to and made grammaticality judgments about grammatical and ungrammatical sentences involving either a local agreement error (e.g., "Every night they talks on the phone") or a long-distance finiteness error (e.g., "He makes the quiet boy talks a little louder"). Electrophysiological (ERP) and behavioral (accuracy) measures were obtained.

RESULTS

Local agreement errors elicited the expected anterior negativity and P600 components in both groups of children. However, relative to the TD group, the P600 effect for the long-distance finiteness errors was delayed, reduced in amplitude, and shorter in duration for the H-SLI group. The children's grammaticality judgments were consistent with the ERP findings.

CONCLUSION

Children with H-SLI seem to be relatively insensitive to the finiteness constraints that matrix verbs place on subject-verb clauses that appear later in the sentence.

Problems with tense marking in children with specific language impairment: not how but when

Many children with specific language impairment (SLI) have persisting problems in the correct use of verb tense, but there has been disagreement as to the underlying reason. When we take into account studies using receptive as well as expressive language tasks, the data suggest that the difficulty for children with SLI is in knowing when to inflect verbs for tense, rather than how to do so. This is perhaps not surprising when we consider that tense does not have a transparent semantic interpretation, but depends on complex relationships between inflections and hierarchically organized clauses. An explanation in terms of syntactic limitations contrasts with a popular morpho-phonological account, the Words and Rules model. This model, which attributes problems to difficulties with applying a rule to generate regular inflected forms, has been widely applied to adult-acquired disorders. There are striking similarities in the pattern of errors in adults with anterior aphasia and children with SLI, suggesting that impairments in appreciation of when to mark tense may apply to acquired as well as developmental disorders.

What influences children's conceptualizations of language input?

PURPOSE

Children learning language conceptualize the nature of input they receive in ways that allow them to understand and construct utterances they have never heard before. This study was designed to illuminate the types of information children with and without specific language impairment (SLI) focus on to develop their conceptualizations and whether they can rapidly shift their initial conceptualizations if provided with additional input.

METHOD

In 2 studies, preschool children with and without SLI were exposed to an artificial language, the characteristics of which allowed for various types of conceptualizations about its fundamental properties. After being familiarized with the language, children were asked to judge test strings that conformed to the input in 1 of 4 different ways.

RESULTS

All children preferred test items that reflected a narrow conceptualization of the input (i.e., items most like those heard during familiarization). Children showed a strong preference for phonology as a defining property of the artificial language. Restructuring the input to the child could induce them to track word order information as well.

CONCLUSION

Children tend toward narrow conceptualizations of language input, but the nature of their conceptualizations can be influenced by the nature of the input they receive.

Visual attentional engagement deficits in children with specific language impairment and their role in real-time language processing

In order to become a proficient user of language, infants must detect temporal cues embedded within the noisy acoustic spectra of ongoing speech by efficient attentional engagement. According to the neuro-constructivist approach, a multi-sensory dysfunction of attentional engagement - hampering the temporal sampling of stimuli - might be responsible for language deficits typically shown in children with Specific Language Impairment (SLI). In the present study, the efficiency of visual attentional engagement was investigated in 22 children with SLI and 22 typically developing (TD) children by measuring attentional masking (AM). AM refers to impaired identification of the first of two sequentially presented masked objects (O1 and O2) in which the O1-O2 interval was manipulated. Lexical and grammatical comprehension abilities were also tested in both groups. Children with SLI showed a sluggish engagement of temporal attention, and individual differences in AM accounted for a significant percentage of unique variance in grammatical performance. Our results suggest that an attentional engagement deficit - probably linked to a dysfunction of the right fronto-parietal attentional network - might be a contributing factor in these children's language impairments.

Electrophysiological correlates of rapid auditory and linguistic processing in adolescents with specific language impairment

Brief tonal stimuli and spoken sentences were utilized to examine whether adolescents (aged 14;3-18;1) with specific language impairments (SLI) exhibit atypical neural activity for rapid auditory processing of non-linguistic stimuli and linguistic processing of verb-agreement and semantic constraints. Further, we examined whether the behavioral and electrophysiological indices for rapid auditory processing were correlated with those for linguistic processing. Fifteen adolescents with SLI and 15 adolescents with normal language met strict criteria for displaying consistent diagnoses from kindergarten through the eighth grade. The findings provide evidence that auditory processing for non-linguistic stimuli is atypical in a significant number of adolescents with SLI compared to peers with normal language and indicate that reduced efficiency in auditory processing in SLI is more vulnerable to rapid rates (200ms ISI) of stimuli presentation (indexed by reduced accuracy, a tendency for longer RTs, reduced N100 over right anterior sites, and reduced amplitude P300). Many adolescents with SLI displayed reduced behavioral accuracy for detecting verb-agreement violations and semantic anomalies, along with less robust P600s elicited by verb-agreement violations. The results indicate that ERPs elicited by morphosyntactic aspects of language processing are atypical in many adolescents with SLI. Additionally, correlational analyses between behavioral and electrophysiological indices of processing non-linguistic stimuli and verb-agreement violations suggest that the integrity of neural functions for auditory processing may only account for a small proportion of the variance in morphosyntactic processing in some adolescents.

Factors affecting accuracy of past tense production in children with specific language impairment and their typically developing peers: the influence of verb transitivity, clause location, and sentence type

PURPOSE

The author examined the influence of sentence type, clause order, and verb transitivity on the accuracy of children's past tense productions. All groups of children, but especially children with specific language impairment (SLI), were predicted to decrease accuracy as linguistic complexity increased.

METHOD

The author elicited past tense productions in 2-clause sentences from 5- to 8-year-old children with SLI (n=14) and their typically developing peers (n=24). The target sentences varied in the type and obligatory nature of the second clause and the number of arguments.

RESULTS

On average, 85% of the responses across all groups and sentence types contained 2 clauses. Fewer 2-clause sentences were produced in the complement clause condition than in the other conditions. Sentence type and clause order, but not argument structure, influenced use of past tense. Children with SLI had a similar but less accurate profile as compared with the age-matched group. The younger mean length of utterance (MLU)-matched group reflected decreased accuracy with each additional source of linguistic complexity.

CONCLUSIONS

Increased syntactic difficulty decreases use of morphology for all children, supporting the hypothesis that processing demands influence morphological accuracy. MLU-matched children, but not children with SLI, were more affected by changes in linguistic complexity. Further work on age-related changes in sentence production is necessary.