Subpopulations in closed-head injury: preliminary results

The cognitive basis for sentence planning difficulties in discourse after traumatic brain injury

PURPOSE

Analyses of language production of individuals with traumatic brain injury (TBI) place increasing emphasis on microlinguistic (i.e., within-sentence) patterns. It is unknown whether the observed problems involve implementation of well-formed sentence frames or represent a fundamental linguistic disturbance in computing sentence structure. This study investigated the cognitive basis for microlinguistic deficits in individuals with TBI.

METHOD

Fifteen nonaphasic individuals with severe TBI and 6 age- and education-matched non brain-injured adults participated in this study. Monologic discourse samples were analyzed for pausing patterns, mazes, errors, and abandoned utterances. Measures of cognitive abilities were correlated with the sentence measures.

RESULTS

The speakers with TBI produced more pauses between clauses (but not within clauses) as well as more mazes than did the non brain-injured speakers. Significant regression models were built. Raven's Coloured Progressive Matrices (Raven, 1965), a measure associated with working memory, predicted pause behavior, and Likenesses-Differences (Baker & Leland, 1967), a measure of executive function, predicted maze behavior.

CONCLUSIONS

Sentence planning impairments following TBI are associated with deficient organization and monitoring of language representations in working memory. These findings suggest that the deficits are due to problems in the recruitment and control of attention for sentence planning. These findings bear on sentence processing models that emphasize the activation, organization, and maintenance of language representations for accurate sentence production.

Evaluating service delivery for speech and swallowing problems following paediatric brain injury: an international survey

RATIONALE, AIMS AND OBJECTIVES

Little is documented about contemporary management of speech and swallowing disorders associated with paediatric acquired brain injury (ABI). It is therefore challenging for clinicians in this field to benchmark their clinical management against current evidence or practices undertaken in other centres. To address this issue, we aimed to provide much-needed baseline data on speech and language pathology management of speech and swallowing disorders associated with childhood ABI. Key objectives were to: (i) determine whether clinicians use formalized referral criteria, clinical guidelines, protocols or care pathways; and (ii) to document the specific assessment and treatment approaches used.

METHODS

Speech and language pathology managers and clinicians at 31 major paediatric rehabilitation centres across Australia, New Zealand, the UK and Ireland were invited to participate in an online survey.

RESULTS

Fifty-one speech and language pathologists responded representing 26 centres (84% response rate). Routine referrals of ABI patients to speech and language pathology occurred relatively infrequently in these centres (12%). Centres utilized assessment protocols (23%) and guidelines (35%) more frequently than treatment guidelines (8%). Multidisciplinary care pathways were applied by 31%. Most centres used adult-based motor speech assessments and informal ('in-house developed') swallowing assessment tools.

CONCLUSIONS

The limited use of referral criteria, protocols, care pathways and guidelines invites the possibility of unequal care, and less than optimal outcomes. Reliance on adult-based or in-house assessments is inappropriate, yet frequently a necessity due to an absence of paediatric-specific tools in this field. Further research is required in parallel with the formation of consensus groups to support the development of: (i) paediatric-specific assessment tools and management approaches; and (ii) clinical protocols and guidelines.

Clinical progression and outcome of dysphagia following paediatric traumatic brain injury: a prospective study

OBJECTIVES

To provide a preliminary clinical profile of the resolution and outcomes of oral-motor impairment and swallowing function in a group of paediatric dysphagia patients post-traumatic brain injury (TBI). To document the level of cognitive impairment parallel to the return to oral intake, and to investigate the correlation between the resolution of impaired swallow function versus the resolution of oral-motor impairment and cognitive impairment.

PARTICIPANTS

Thirteen children admitted to an acute care setting for TBI.

MAIN OUTCOME MEASURES

A series of oral-motor (Verbal Motor Production Assessment for Children, Frenchay Dysarthria Assessment, Schedule for Oral Motor Assessment) and swallowing (Paramatta Hospital's Assessment for Dysphagia) assessments, an outcome measure for swallowing (Royal Brisbane Hospital's Outcome Measure for Swallowing), and a cognitive rating scale (Rancho Level of Cognitive Functioning Scale).

RESULTS

Across the patient group, oral-motor deficits resolved to normal status between 3 and 11 weeks post-referral (and at an average of 12 weeks post-injury) and swallowing function and resolution to normal diet status were achieved by 3-11 weeks post-referral (and at an average of 12 weeks post-injury). The resolution of dysphagia and the resolution of oral-motor impairment and cognitive impairment were all highly correlated.

CONCLUSION

The provision of a preliminary profile of oral-motor functioning and dysphagia resolution, and data on the linear relationship between swallowing impairment and cognition, will provide baseline information on the course of rehabilitation of dysphagia in the paediatric population post-TBI. Such data will contribute to more informed service provision and rehabilitation planning for paediatric patients post-TBI.

Predicting social and functional outcomes for individuals sustaining paediatric traumatic brain injury

OBJECTIVE

To determine the efficacy of models employing the classification of severity of injury, based on either GCS scores or clinical findings using standardized test scores for Occupational Therapy, Physiotherapy and Psychology in predicting outcomes associated with paediatric traumatic brain injury (TBI).

METHOD

Medical records were reviewed to obtain GCS scores and standardized tests used in the clinically based classification of severity of injury for 30 individuals who sustained a paediatric TBI and were patients of a brain injury treatment programme. Interviews were conducted with parents to obtain current data on social participation, cognitive functioning and environmental factors.

RESULTS

Three variables emerged as significant predictors of outcome: age at injury, clinical ratings of injury severity and environmental factors.

CONCLUSION

Findings offer preliminary support for the idea that a combination of factors, including age at injury, clinical expertise and the environment, provide the best estimate of long-term outcome.

Hong Kong family caregivers' stress and coping for people with brain injury

Chinese families,in caring for their members with a brain injury have faced longterm burdens for which they were usually ill prepared. The complicated. Intertwined disability- and family-related factors appeared to be affecting their effective family coping especially in the context of Chinese families. The present study examined the impact of brain injury, which was based on analysing individual families' differences, and conceptualized through an empowerment framework for possible guidance in designing appropriate, indigenous family intervention. A total of 50 families with a brain injured members were successfully recruited by convenient sampling to attend an individual interview. Discussion was guided by open-ended questions. All the families' responses to questions, and the verbatim transcripts of long interviews of four randomly selected families, were used to construct themes of coping strategies. They were found to show the typical coping strategies of people facing stress, including shock and uncertainty, which were suggested to be related closely to the nature of brain injury, especially if the injury was traumatic in nature, and their difficulties in managing problems that were novel, unpredictable and global in nature (affecting physical and cognitive functions, personality change and social integration). The physical and psychological burdens involved in day-to-day caring for members with brain injury were unanimously reflected in the interviews. Further content analysis of the long interviews of four selected families showed that some families coped well and some did not. For those successful coping situations, families reported that they became empowered after the onset of their members' brain injury. They expressed possible factors leading to better adjustment, which included setting clear personal expectations, the flexibility to adjust life goals, a desire to master the situation, strong motivation, awareness of their own powerless state and willingness to ask for help from different sources. The results indicated that families cope with a brain-injured member differently, depending on the family's structure, and this should be explored further for the development of intervention guidelines.

Exploring the cognitive basis of right-hemisphere pragmatic language disorders

Despite considerable interest in the linguistic dimensions of right-hemisphere (RH) pragmatic language disorders, the cognitive bases for these are rarely examined. This study investigated two alternative explanations. First, RH pragmatic language disorders may reflect failure of the RH to synthesise incoming and preexisting information, verbal and visuospatial. In this case language and visuospatial performance should covary. Alternatively such disorders may reflect damage to executive control of all cognitive processing secondary to frontal system failure. In this case language and executive function would be associated. Further, in the former case, subjects should be insensitive to the plausibility of information, whereas in the latter they would be fixated by the literal meaning of information and therefore highly sensitive to plausibility. Eighteen patients with RH damage were compared to 20 matched controls on a range of language and neuropsychological tasks. Pragmatic performance was generally correlated to RH (visuospatial) function, not to executive function. Nonetheless RH patients were found to have problems ignoring plausibility. Thus the specific RH hypothesis described needs to be reconsidered.

Conceptual and methodological challenges in discourse assessment with TBI speakers: towards an understanding

The primary objective of this paper is to review theoretical and methodological literature pertaining to the clinical evaluation of discourse abilities in speakers who have sustained traumatic brain injury (TBI). A brief history of the study of discourse impairment in this population is followed by consideration of the following issues: (1) sampling (genres selected, the physical setting in which sampling takes place, the relationship between speakers, elicitation techniques, presence of recording devices, the number of samples required, and transcription); (2) measurement; (3) the relationship between sampling and measurement; (4) other approaches to discourse assessment (self and close other report); (5) consideration of the criterion of 'normal' which clinicians should employ; (6) the relationship between discourse impairment and measures of executive function; and (7) the relationship between discourse impairment and seventy of injury. Recommendations arising from a critical review of these domains are made for both clinical practice and research.

Cognitive-linguistic subgroups in closed-head injury

This study examined variability in the interrelationship between language skill and neuropsychological function within a group of 25 severe closed head injury (CHI) subjects and 23 matched controls. All subjects underwent a battery of standardized language and neuropsychological tests. Cluster analyses were conducted to determine whether the CHI sample was universally or differentially impaired. Further subgroup analysis using a Q-type factor analysis outlined the differences in performance profiles within the group of CHI subjects. Results support the hypothesis that while some deficits were common to all CHI subjects, impairments delineated by whole group analysis do not necessarily represent universal impairments. In particular, ability to perform tasks involving auditory comprehension, naming, verbal memory, visual memory and visuospatial skills appeared to be important components in group differentiation. The cognitive-linguistic impairments which were common to all CHI subjects and considered to be the 'cardinal' cognitive-linguistic deficits following severe CHI were deficits in lexical-semantic and sentential semantic skills, verbal fluency, complex auditory comprehension, and attentional operations. Profile analysis revealed the existence of a double dissociation between performances on naming and verbal memory tasks and performances on visually related cognitive tasks. Results are discussed with reference to findings on previous studies of subgroups in the CHI population.

Towards a conceptualization of language and cognitive impairment in closed-head injury: use of clinical measures

Language deficits following closed-head injury (CHI) are widely considered as impairments secondary to the cognitive disruptions common to closed-head injury. In addition, the use of standardized measures to assess the functioning of the language system in closed-head injury has mostly been limited to aphasia test batteries which examine primary language functions only. This has resulted in generalizations as to the integrity of the language system following closed-head injury, and as a consequence, consideration of the contribution of the language system to the achievement of communicative competence in this population has been minimized. This paper presents a framework in which the functional language system is identified as a hierarchical system containing primary and higher-order language processes involved in reciprocal relationships with cognitive functions at each level. A group of 25 closed-head injury subjects and 23 demographically matched control subjects were examined for linguistic proficiency using a battery of standardized tests which investigated the language system across a hierarchy of complexity, structure and predictability. In addition, 23 of the closed-head subjects were administered a comprehensive neuropsychological test battery in order to determine the nature and extent of concomitant impairments in cognitive processes and their relationship with impairments in the language system. The language battery was found to consistently discriminate between the control and clinical groups indicating that the linguistic system is significantly impaired following CHI, with the lexical-semantic system being the most vulnerable to disruption. A strong influential relationship between language and cognitive processes was statistically confirmed and the nature of the relationship between aspects of language and cognition further delineated.