Assessment of syntax after adolescent brain injury: effects of memory on test performance

Contribution of Working Memory and Inferencing to Narrative Discourse Comprehension and Production in Traumatic Brain Injury

PURPOSE

The goal of this study was to identify some potential key cognitive and communicative processes underlying narrative discourse ability following traumatic brain injury (TBI). Specifically, this study (a) investigated the contribution of working memory (WM) and inferencing to narrative discourse comprehension and production; (b) tested key assumptions posited by the Structure Building Framework (SBF), a discourse model; and (c) evaluated the potential for inferencing to contribute to discourse ability beyond a shared variance with WM.

METHOD

Twenty-one individuals with TBI completed six tasks yielding seven measures: verbal and nonverbal WM updating (WMU-V and WMU-NV, respectively), predictive inferencing, the Discourse Comprehension Test (DCT), a picture story comprehension (PSC) task, and story retelling (story grammar and story completeness). Regression analyses were performed using WM and inferencing as predictors for narrative performance.

RESULTS

WM measures were significant predictors of DCT performance and approached significance as predictors of PSC. Inferencing approached significance as a unique predictor for the DCT and story completeness. WMU-V and WMU-NV were highly collinear, and neither WM measure predicted discourse outcomes over and above the other's contribution.

CONCLUSIONS

WM was more strongly associated with comprehension processes, whereas inferencing may be associated with both comprehension and production outcomes. Findings were interpreted as supporting SBF assumptions of domain generality of cognitive processes and mechanisms involved in discourse while also challenging assumptions that the same cognitive substrates are marshaled for comprehension and production processes.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.23148647.

Bayesian Generalized Linear Mixed-Model Analysis of Language Samples: Detecting Patterns in Expository and Narrative Discourse of Adolescents With Traumatic Brain Injury

Purpose Generalized linear mixed-model (GLMM) and Bayesian methods together provide a framework capable of handling a wide variety of complex data commonly encountered across the communication sciences. Using language sample analysis, we demonstrate the utility of these methods in answering specific questions regarding the differences between discourse patterns of children who have experienced a traumatic brain injury (TBI), as compared to those with typical development. Method Language samples were collected from 55 adolescents ages 13-18 years, five of whom had experienced a TBI. We describe parameters relating to the productivity, syntactic complexity, and lexical diversity of language samples. A Bayesian GLMM is developed for each parameter of interest, relating these parameters to age, sex, prior history (TBI or typical development), and socioeconomic status, as well as the type of discourse sample (compare-contrast, cause-effect, or narrative). Statistical models are thoroughly described. Results Comparing the discourse of adolescents with TBI to those with typical development, substantial differences are detected in productivity and lexical diversity, while differences in syntactic complexity are more moderate. Female adolescents exhibited greater syntactic complexity, while male adolescents exhibited greater productivity and lexical diversity. Generally, our models suggest more advanced discourse among adolescents who are older or who have indicators of higher socioeconomic status. Differences relating to lecture type were also detected. Conclusions Bayesian and GLMM methods yield more informative and intuitive results than traditional statistical analyses, with a greater degree of confidence in model assumptions. We recommend that these methods be used more widely in language sample analysis. Supplemental Material https://doi.org/10.23641/asha.14226959.

Microstructural and Fluency Characteristics of Narrative and Expository Discourse in Adolescents With Traumatic Brain Injury

Purpose The purpose of this exploratory study was to identify specific microstructural and fluency differences in expository and narrative summaries produced by students with a traumatic brain injury (TBI) compared to students with typical development (TD). Method Five adolescents with TBI and 5 matched peers with TD verbally summarized 1 narrative and 2 expository (compare-contrast, cause-effect) lectures, creating 30 summaries. Researchers transcribed summaries and used paired t tests to analyze between-group differences in microstructural measures (productivity, lexical diversity, syntactic complexity), mazing behaviors, and pausing patterns. Results Youth with TBI produced significantly fewer utterances than teens with TD in both expository contexts, whereas youth with TD produced a significantly greater mean length of C-unit than teens with TBI in the narrative summary only. Youth with TBI produced significantly fewer filled pauses per utterance than did youth with TD during the cause-effect summary only and significantly more pauses per utterance and within-clause pauses per utterance during the compare-contrast summary. Where findings were statistically significant, effect sizes were large. There were no statistically significant between-group differences in mazing or pausing behaviors during narrative summary production. Conclusions This study is the 1st to compare microstructural and fluency characteristics in teens with TBI and those without when producing verbal summaries of a narrative and 2 types of expository passages. Findings from this study reinforce the need to expand research focusing on expository discourse tasks and identify variables that may be prone to disruption following TBI. Future work is needed to confirm whether identified differences correspond to true discourse difficulties. Supplemental Material https://doi.org/10.23641/asha.9807812.

Exploring Summarization Differences for Two Types of Expository Discourse in Adolescents With Traumatic Brain Injury

PURPOSE

Annually, nearly 700,000 U.S. children and adolescents experience a traumatic brain injury (TBI). Many of them struggle academically, despite failing to qualify for special education services because their cognitive communication impairments are subtle.

METHOD

In this exploratory study, five adolescents with TBI provided verbal summaries of two expository lectures (compare-contrast, cause-effect) and participated in cognitive and expressive syntax testing. Their performance on these tasks was compared descriptively to that of 50 adolescents with typical development.

RESULTS

For adolescents with TBI, mean summary quality scores for both exposition types were at least 1 SD lower than those of adolescents with typical development and notably 2 SDs below for the cause-effect passage. The adolescents with TBI who had below-average cognitive scores showed better performance on compare-contrast summaries compared to cause-effect, whereas the majority of adolescents with typical development showed the opposite tendency.

CONCLUSIONS

These results provide preliminary evidence that students with TBI, particularly those with cognitive deficits, may struggle with expository discourse despite acceptable performance on a measure of expressive syntax. This study also indicates that researchers should explore how students with TBI perform on academically relevant discourse tasks in order to inform future assessment and intervention efforts.

SUPPLEMENTAL MATERIALS

https://doi.org/10.23641/asha.5572786.

Executive Function and Ambiguous Sentence Comprehension

PURPOSE

Sentence comprehension is a critical skill in today's literate society. Recent evidence suggests that processing and comprehending language taps cognitive as well as linguistic abilities, a finding that has critical import for clinicians who have clients with language disorders. To promote awareness of the impact of cognition, especially executive function (EF) and working memory (WM), this opinion article presents current views of how sentences are processed and links the various steps of the process to specific EF and WM subcomponents.

METHOD

The article focuses on ambiguous sentences, pointing out the similar types of processing needed when resolving an ambiguity and performing EF tasks.

RESULTS

We discuss the potential overlap between the neurobiology of sentence processing and EF and the evidence supporting a link between EF and sentence processes.

CONCLUSION

Awareness of the potential role of EF and WM in sentence comprehension will help clinicians be more aware of potential cognitive-linguistic deficits in their clients. Future research will help to clarify the link between EF and sentence comprehension.

Cognitive-communication disorders in children with traumatic brain injury

Children with moderate to severe traumatic brain injury (TBI) are at risk of developing cognitive-communication disorders that have devastating effects on their school life, family life, and social life. These problems can be difficult for families to describe and may be overlooked by community-based providers who are unfamiliar with TBI sequelae. To support the identification and management of cognitive-communication disorders, we review the common signs and symptoms of these disorders in children with TBI and discuss principles of assessment and intervention.

Single Case Studies as Seeds

Single case studies are research studies of single participants. They explore new ideas and can suggest extensions in methods and for treatment (Yin, 1984). In this article the case study refers only to conditions observed and is limited to what was observed from these comparisons between normal function and patterns of specific conditions. This does not reflect the theory of a formal case study but rather it is an attempt to show the case study and simple computer modelling as learning tools in a complex environment. Critics of case study methodology cite small case numbers as not having grounds for establishing reliability or generalization of findings and that the intensity of exposure needed for thorough case studies could bias the research findings subtracting from researcher objectivity. Early computer models were used to simulate the function of the brain and provide partial answers. They provided insight into the understanding of complex function. In recent history, computer models and case studies have been cast aside in favor of live brain imaging and complex biochemical reactions. It is good to remember that these tools brought us to the place of knowledge we enjoy today and have enlarged diagnostic and treatment choices. They are still valuable and inexpensive methods that can impact the imaginations of neuroscientists and kindle their passions to solve the complexities of the human mind one problem at a time. Greater rigor can be easily maintained by adopting a format whereby a patient would be assessed by a fully standardized neuropsychological battery and the performance then compared to large sample of normative data. The formal study is important for generalization of findings across conditions and can be applied once normative data has been collected as a basis for comparison.

Spoken Persuasive Discourse Abilities of Adolescents With Acquired Brain Injury

Purpose

The aim of this study was to examine the performance of adolescents with acquired brain injury (ABI) during a spoken persuasive discourse task. Persuasive discourse is frequently used in social and academic settings and is of importance in the study of adolescent language.

Method

Participants included 8 adolescents with ABI and 8 peers without ABI who were matched for age, gender, and education. A spoken persuasive discourse task requiring participants to express their opinion on a topic was administered, and the 2 groups were compared on measures of language productivity, syntactic complexity, and language content. In addition, the relationship between working memory and discourse production was explored.

Results

There were no statistically significant group differences on measures of language productivity or syntactic complexity, with the exception of the use of mazes, which was more prevalent in the discourse of the group with ABI. However, there were significant differences in language content, with age-matched peers producing more than twice as many supporting reasons and far fewer tangentially related utterances than the adolescents with ABI.

Conclusions

Persuasive discourse production was affected following ABI. Given the importance of persuasive discourse in social and academic situations, further investigations into factors that influence discourse production in adolescents with ABI are warranted.

Language and memory profiles of adolescents with traumatic brain injury

The performance of adolescents who suffered a traumatic brain injury in childhood, on language comprehension tasks with varying working memory demands, was examined. It was hypothesized that adolescents with a traumatic brain injury would perform more poorly than their non-injured peers, particularly on those tasks with high working memory demands. A case study design allowed for both group and intra-participant comparisons. A battery of language comprehension and working memory tasks was administered to six adolescents aged 12-16 years. Their performance was compared with six individually age-matched peers with typical development and to the normative data of the standardized tests. Intra-participant performance was examined by comparing results across language tasks that varied in working memory demands. Analysis revealed that individuals with traumatic brain injury performed poorly compared with their age-matched peers. However, the pattern of listening comprehension impairment differed across individuals and marked variability within the comprehension profiles for some individuals with traumatic brain injury was evident. Language comprehension tasks with high working memory demands generally posed the most difficulty for individuals with traumatic brain injury.

Inference comprehension of adolescents with traumatic brain injury: A working memory hypothesis

This study investigated inference comprehension performance in adolescents who had suffered a traumatic brain injury (TBI). Using stimuli adapted from Lehman-Blake and Tompkins, participants listened to short paragraphs that varied according to the working memory demands of the task and answered comprehension questions that required inferences to be generated. Six adolescents, aged 12-16 years, who had suffered a TBI prior to the age of 10 years, were assessed and their performance was compared to six individually age-matched peers with typical development. Analysis revealed that individuals with TBI did not differ from non-injured peers in their understanding of inferences when the storage demands of the task were minimized. However, when storage demands were high, adolescents with TBI performed poorly compared to their age-matched peers. Results are discussed relative to a working-memory hypothesis of impairment following TBI.

Working memory and proverb comprehension in adolescents with traumatic brain injury: A preliminary investigation

PRIMARY OBJECTIVE

This study investigated the relationship between working memory and comprehension of low-familiarity proverbs in adolescents with traumatic brain injury (TBI).

METHODS AND PROCEDURES

Ten adolescents, aged 12-21 years who had suffered a TBI prior to the age of 10 years and 10 individually age-matched peers with typical development participated in the study. The participants listened to short paragraphs containing a proverb and interpreted the meaning of the proverb using a forced-choice task. In addition, participants engaged in a task that evaluated working memory ability.

MAIN OUTCOMES AND RESULTS

Analysis revealed that individuals with TBI differed from their non-injured peers in their understanding of proverbs. In addition, working memory capacity influenced performance for all participants.

CONCLUSIONS

The importance of considering working memory when evaluating figurative language comprehension in adolescents with TBI is highlighted. Implications for future research, particularly with regard to varying working memory and task demands, are considered.

Update on a clinical measure for the assessment of problem solving

PURPOSE

The Rapid Assessment of Problem Solving test (RAPS) is a clinical measure of problem solving based on the 20 Questions Test. This article updates clinicians on the RAPS, addresses questions raised about the test in an earlier article (R. C. Marshall, C. M. Karow, C. Morelli, K. Iden, & J. Dixon, 2003a), and discusses the clinical utility of the RAPS.

METHOD

The RAPS was administered to 373 normal adults. Tests were analyzed to assess the impact of demographic, psychometric, and other factors on performance on the RAPS. To determine the effects of strategy selection on test scores, participants were assigned to novel, category-focused, or mixed strategy groups based on the types of first questions asked.

RESULTS

Normal participants exhibited a range of performance levels on the RAPS. Participants in the novel strategy group performed significantly better than the participants in 2 other strategy groups.

CONCLUSIONS

The RAPS is a clinically useful tool to examine problem solving that is easy to administer and to score. Findings suggest clinicians can use the RAPS with greater confidence than was the case 4 years ago. The RAPS is now part of the public domain and may be used by clinicians to assess clients' problem-solving deficits.

Executive Functions Following Traumatic Brain Injury in Young Children: A Preliminary Analysis

To examine executive processes in young children with traumatic brain injury (TBI), we evaluated performance of 44 children who sustained moderate-to-severe TBI prior to age 6 and to 39 comparison children on delayed response (DR), stationary boxes, and spatial reversal (SR) tasks. The tasks have different requirements for holding mental representations in working memory (WM) over a delay, inhibiting prepotent responses, and shifting response set. Age at the time of testing was divided into 10- to 35- and 36- to 85-month ranges. In relation to the community comparison group, children with moderate-to-severe TBI scored significantly lower on indexes of WM/inhibitory control (IC) on DR and stationary boxes tasks. On the latter task, the Age x Group interaction indicated that performance efficiency was significantly reduced in the older children with TBI relative to the older comparison group; performance was similar in younger children irrespective of injury status. The TBI and comparison groups did not differ on the SR task, suggesting that shifting response set was not significantly altered by TBI. In both the TBI and comparison groups, performance improved with age on the DR and stationary boxes tasks. Age at testing was not significantly related to scores on the SR task. The rate of acquisition of working memory (WM) and IC increases steeply during preschool years, but the abilities involved in shifting response set show less increase across age groups (Espy, Kaufmann, & Glisky, 2001; Luciana & Nelson, 1998). The findings of our study are consistent with the rapid development hypothesis, which predicts that skills in a rapid stage of development will be vulnerable to disruption by brain injury.

Linguistic outcomes following traumatic brain injury in children

Recent studies of outcome after traumatic brain injury (TBI) emphasize the adverse effect of diffuse brain injury on linguistic development. This article reviews studies of lexical development, discourse processes, and reading in children and adolescents with TBI. The child's developmental level at the time of injury is related to the pattern of deficits. Young children who sustain severe TBI are particularly vulnerable to linguistic deficits at both lexical and discourse levels. TBI in older children and adolescents preferentially disrupts higher-order discourse functions. The contribution of deficits in fundamental processes, such as working memory and processing speed, to linguistic outcomes requires further investigation.

The effect of elicitation task on discourse coherence and cohesion in adolescents with brain injury

Six adolescents with traumatic brain injury and six adolescents who had been hospitalized for an illness or injury not affecting the brain were administered two narrative tasks designed to vary in their demand for spontaneous organization of information and minimize the requirement for new learning. The discourse topics--a description of each subject's injury and hospitalization, and a re-telling of a current event--were chosen to be representative of discourse in adolescent daily living. Narratives produced by subjects in each group were compared between the two tasks on measures of coherence and cohesion. Subjects in both groups produced significantly more coherent and cohesive narratives in the personal event task than in the current event task, and there was no significant difference between groups. The results are discussed in relation to face validity of language tasks for adolescents, and the multiple factors contributing to adolescent social discourse.

Language Testing in Adolescents With Brain Injury

The validity of the Clinical Evaluation of Language Fundamentals-Third Edition (CELF-3, Semel, Wiig, & Secord, 1995) for the identification and description of language disorders following traumatic brain injury (TBI) was considered in 11 adolescents with TBI. In general, the CELF-3 identified only the individuals who had previously been diagnosed as language impaired, not the individuals with verbal information processing impairments but no diagnosis of language impairment. The test did not permit the identification of strengths and weaknesses.

Intercorrelations among subtest standard scores were as high in the TBI group as in the standardization sample, which is consistent with the CELF-3 being a one-factor test. Test performance may have been influenced by the interaction of the subjects’ memory abilities and the subtests’ memory demands, although this relationship was not statistically significant in the present data.