Article 7: Categorization, deductive reasoning, and self-awareness: association to everyday competence in persons with acute brain injury

Objective: To examine the contribution of self-awareness and executive function to the performance of instrumental activities of daily living (IADLs) among adults with acute brain injury. Design: Correlational research design. Setting: Acute neurosurgery unit. Participants: 40 men and women between the ages of 21 to 84 years. Interventions: Not applicable. Main Outcome Measures: Performance on the Toglia Category Assessment (TCA), the Deductive Reasoning Test (DRT), and the Revised Observed Tasks of Daily Living served as dependent variables of interest. Self-awareness was measured using subtests of the TCA and DRT. Results: Categorization and deductive reasoning contributed significantly to IADL performance, suggesting that both executive measures can serve as predictors of IADL in persons with brain injuries. Self-awareness contributed significantly to IADL performance, but its contribution was mediated through categorization ability. Executive function correlated significantly with posttest IADL performance estimation, but not with IADL performance predictions. Conclusions: Executive functions, as well as self-awareness, predicted ADL performance in persons with brain injury. The results are discussed within the framework of a conceptual model that illustrates the multifaceted nature of executive function and its relationship to self-awareness and everyday functional competence.     

Construct-related validity of the Toglia Category Assessment and the Deductive Reasoning test with children who are typically developing.

OBJECTIVE: Both classification and deductive reasoning are essential cognitive components underlying any learning process and, therefore, are important to assess in children with developmental or learning disabilities. The aim of this study was to establish construct-related validity of the Toglia Category Assessment (TCA) and the Deductive Reasoning test, which were originally developed to evaluate adults with brain injury. This study represents the first step in validating and adapting the two tests for children who are typically developing. METHOD: The study population consisted of 235 children without disabilities in 6 different age groups (from 5-11 years of age). Both the TCA and the Deductive Reasoning test were administered to all participants. RESULTS: The results of the study indicate significant differences in the average performance of children in several age groups on both the TCA and the Deductive Reasoning test, but they do not show differences among all the groups. Children could not predict their ability in either test, but most were able to estimate their ability after actual performance of the TCA. A significant correlation was found only for the 5-year-olds and 7-year-olds between the Deductive Reasoning test final score and the children's estimation of their performance. CONCLUSION: The findings of this study support the suitability of the TCA and the Deductive Reasoning test for use with children who are typically developing. We recommend that both tools be studied further to amplify their validity.     

Evaluating the roles of the inferior frontal gyrus and superior parietal lobule in deductive reasoning: an rTMS study

This study used off-line repetitive transcranial magnetic stimulation (rTMS) to examine the roles of the superior parietal lobule (SPL) and inferior frontal gyrus (IFG) in a deductive reasoning task. Subjects performed a categorical syllogistic reasoning task involving congruent, incongruent, and abstract trials. Twenty four subjects received magnetic stimulation to the SPL region prior to the task. In the other 24 subjects, TMS was administered to the IFG region before the task. Stimulation lasted for 10min, with an inter-pulse frequency of 1Hz. We found that bilateral SPL (Brodmann area (BA) 7) stimulation disrupted performance on abstract and incongruent reasoning. Left IFG (BA 45) stimulation impaired congruent reasoning performance while paradoxically facilitating incongruent reasoning performance. This resulted in the elimination of the belief-bias. In contrast, right IFG stimulation only impaired incongruent reasoning performance, thus enhancing the belief-bias effect. These findings are largely consistent with the dual-process theory of reasoning, which proposes the existence of two different human reasoning systems: a belief-based heuristic system; and a logic-based analytic system. The present findings suggest that the left language-related IFG (BA 45) may correspond to the heuristic system, while bilateral SPL may underlie the analytic system. The right IFG may play a role in blocking the belief-based heuristic system for solving incongruent reasoning trials. This study could offer an insight about functional roles of distributed brain systems in human deductive reasoning by utilizing the rTMS approach.     

Levels of self-awareness after acute brain injury: how patients' and rehabilitation specialists' perceptions compare

OBJECTIVE: To examine self-awareness regarding performance on 4 daily living tasks and to test theoretical predictions for a model of self-awareness in persons with acquired brain injury. DESIGN: A comparative design examining the level of self-awareness recorded by patients and actual patient performance as judged by rehabilitation clinicians. SETTING: A community-based residential center providing comprehensive rehabilitation services to persons with acquired brain injury. PARTICIPANTS: Fifty-five persons with acquired brain injury and the identified potential to return to independent function in the community. Ten subjects without brain injury provided comparison data. INTERVENTION: Information was collected by using patient self-report, clinician rating of patient performance, patient rating of non-brain-injured subjects, and clinician rating of non-brain-injured subjects. MAIN OUTCOME MEASURES: Three self-awareness criteria were examined: intellectual, emergent, and anticipatory. Self-awareness was rated for 3 tasks: dressing, meal planning, and money management. RESULTS: Statistically significant differences (p <.05) were found for all levels of self-awareness across the 3 tasks. Persons with brain injury judged their abilities higher than clinician ratings of actual performance. No statistical support was found for a hierarchy among intellectual, emergent, and anticipatory self-awareness. CONCLUSIONS: No evidence was found supporting a hierarchy among levels of self-awareness as defined and measured in the present study. New methods for operationally defining intellectual, emergent, and anticipatory self-awareness are necessary to examine the relationship between self-awareness and performance.     

Reliability and validity of the Toglia Category Assessment Test.

The aim of this study was to establish interrater reliability, internal consistency reliability, and both concurrent and discriminant validity for the Toglia Category Assessment (TCA), a test of cognitive categorization. This study was based on an examination of categorization skills in clinical samples, using both the Toglia Category Assessment as well as the Riska Object Classification (ROC) test. The study sample consisted of 35 adult persons with brain-injury and 35 persons with chronic schizophrenia (n = 70). Correlations between scores of the two different tests and the two different samples were computed using Pearson's Product Moment Correlation Coefficients. Both inter-rater reliability, internal consistency, and concurrent validity were established for the TCA. These results suggest that the Toglia Category Assessment and Riska Object Classification tests may address different cognitive abilities. The Toglia Category Assessment appears to be a more sensitive test than the Riska Object Classification in that it provides an elaborate cognitive profile.     

Impairment and partial recovery of medical decision-making capacity in traumatic brain injury: a 6-month longitudinal study

OBJECTIVE: To investigate empirically change in medical decision-making capacity (MDC) in patients with traumatic brain injury (TBI). DESIGN: Longitudinal study comparing control and TBI groups at hospitalization and at 6 months postinjury. SETTING: Inpatient brain injury rehabilitation unit. PARTICIPANTS: Twenty healthy controls and 24 patients with moderate to severe TBI. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: MDC was measured by using the Capacity to Consent to Treatment Instrument (CCTI). The CCTI evaluates performance on a series of 4 accepted consent abilities, or standards: S1 (evidencing/communicating choice), S3 (appreciating consequences), S4 (reasoning about treatment), and S5 (understanding the treatment situation and choices), and 1 experimental standard [S2] (making the reasonable treatment choice when the alternative choice is unreasonable). In addition, TBI patients were assigned 1 of 3 capacity outcomes (capable, marginally capable, incapable) for each standard. RESULTS: At hospitalization, TBI patients performed equivalently with controls on standards S1 and [S2] but significantly below controls on S3 ( P <.001), S4 ( P <.02), and S5 ( P <.001). At 6-month follow-up, TBI patients showed significant within-group improvement on these 3 standards (S3, S4, S5) but continued to fall significantly below controls on S3 ( P <.006) and S5 ( P <.001). A group by time interaction emerged on S5 ( P <.02). The TBI group showed increasing proportions of capable outcomes on all standards over the 6 months. CONCLUSIONS: Patients with TBI showed initial impairment and subsequent partial recovery of MDC over a 6-month period. Complex consent abilities of appreciation, reasoning, and understanding were significantly impaired in hospitalized acute TBI patients. At follow-up, TBI patients showed substantial recovery of reasoning and partial recovery of appreciation and understanding consent abilities. The study suggests the importance in the rehabilitation setting of serial evaluations of MDC in patients with TBI.     

Interrater reliability and discriminant validity of the deductive reasoning test.

OBJECTIVE: The purpose of this study was to determine the interrater reliability and discriminant validity of Toglia's Deductive Reasoning test for individuals with brain injuries. METHOD: Forty-two individuals with brain injuries and 51 participants without disabilities ranging in age from 18 to 84 years were given the Deductive Reasoning test three consecutive times. A between groups repeated measure design was used to examine differences between the two groups in performance of the Deductive Reasoning test across the three trials. RESULTS: An interclass correlation coefficient (ICC) was statistically significant, indicating good interrater reliability for participants without disabilities. A repeated measures analysis of variance (ANOVA) comparing performance across trials and between groups revealed a significant group main effect, F(1,91) = 52.68, p < .001, thus, participants with brain injuries performed significantly lower on the test than participants without disabilities. This analysis also revealed a significant increase in all participants' scores across trials, F(1.63, 148.67) = 35.094, p < .001. CONCLUSION: Findings confirm acceptable interrater reliability of the Deductive Reasoning test. Further, comparison of the performance of the two groups supports the discriminant validity of the Deductive Reasoning test for individuals with brain injuries. Thus, the Deductive Reasoning test was found to be an appropriate, valid, and reliable assessment tool for occupational therapists to assess deductive reasoning skills in individuals with brain injuries. Additional research is needed to continue to investigate the psychometric value of the Deductive Reasoning test so that clinicians and researchers can use it appropriately.     

Comparison of individual, group and combined intervention formats in a randomized controlled trial for facilitating goal attainment and improving psychosocial function following acquired brain injury.

OBJECTIVE: To compare individual, group and combined intervention formats for improving goal attainment and psychosocial function following acquired brain injury. DESIGN: Randomized controlled trial, waiting list controls. PARTICIPANTS: Thirty-five participants with a mean time of 5.29 years (standard deviation = 3.9) since acquired brain injury were randomly allocated into 6 groups involving an intervention or waiting list control condition for 1 of 3 intervention formats. METHODS: Interventions were 3 h/week for 8 weeks. Formats included: group-based support (n = 12), individual occupation-based support (n = 11), and a combined group and individual support intervention (n = 12). Participant outcomes were examined at pre-, post-, and 3-month follow-up assessment on the Canadian Occupational Performance Measure, Patient Competency Rating Scale, and Brain Injury Community Rehabilitation Outcome 39 Scales. RESULTS: Overall, the findings indicated that the individual intervention component appeared to contribute particularly to gains in performance in goal-specific areas. The combined intervention was associated with maintained gains in performance and satisfaction. However, gains in behavioural competency and psychological well-being were more likely to occur after the group and individual interventions. CONCLUSION: These findings generally support the efficacy of brief intervention formats following acquired brain injury, although further research is needed to examine clients' suitability for particular interventions.     

Functional neuroanatomy of deductive inference: a language-independent distributed network

Studies of brain areas supporting deductive reasoning show inconsistent results, possibly because of the variety of tasks and baselines used. In two event-related functional magnetic imaging studies we employed a cognitive load paradigm to isolate the neural correlates of deductive reasoning and address the role (if any) of language in deduction. Healthy participants evaluated the logical status of arguments varying in deductive complexity but matched in linguistic complexity. Arguments also varied in lexical content, involving blocks and pseudo-words in Experiment I and faces and houses in Experiment II. For each experiment, subtraction of simple from complex arguments (collapsing across contents) revealed a network of activations disjoint from regions traditionally associated with linguistic processing and also disjoint from regions recruited by mere reading. We speculate that this network is divided into "core" and "support" regions. The latter include left frontal (BA 6, 47) and parietal (BA 7, 40) cortices, which maintain the formal structure of arguments. Core regions, in the left rostral (BA 10p) and bilateral medial (BA 8) prefrontal cortex, perform deductive operations. Finally, restricting the complex-simple subtraction to each lexical content uncovered additional activations which may reflect the binding of logical variables to lexical items.     

The prevalence of disability from chronic conditions due to injury among adults ages 18-69 years: United States, 1994

Purpose: To describe the causes and determine the prevalence of disability from chronic conditions due to injury among US civilian non-institutionalized persons aged 18-69 years. Methods: Data from the National Health Interview Survey Disability (NHIS-D) Supplement Phase I, United States 1994 were analysed and six disability categories were examined: activities of daily living (ADL), instrumental activities of daily living (IADL), functional activities (FA), sight, hearing, and communication. Results: In 1994, 5.6 million persons aged 18-69 years reported a disability because of a chronic condition that was caused by injury. The prevalence of ADL disability due to chronic conditions caused by injury was 370 per 100000 population; IADL disability was 1256; FA disability was 2512; sight was 231; hearing was 339; and communication was 91 per 100000 population. Fifty per cent of ADL, IADL, and FA disabilities were attributed to motor vehicle crashes and falls, as were 31% of sight, 19% of hearing, and 23% of communication disabilities. Conclusions: Though these estimates may be conservative, this study indicates that injury is a major cause of disability in addition to a leading cause of death in the US.     

The prevalence of disability from chronic conditions due to injury among adults ages 18-69 years: United States, 1994

Purpose: To describe the causes and determine the prevalence of disability from chronic conditions due to injury among US civilian non-institutionalized persons aged 18-69 years. Methods: Data from the National Health Interview Survey Disability (NHIS-D) Supplement Phase I, United States 1994 were analysed and six disability categories were examined: activities of daily living (ADL), instrumental activities of daily living (IADL), functional activities (FA), sight, hearing, and communication. Results: In 1994, 5.6 million persons aged 18-69 years reported a disability because of a chronic condition that was caused by injury. The prevalence of ADL disability due to chronic conditions caused by injury was 370 per 100000 population; IADL disability was 1256; FA disability was 2512; sight was 231; hearing was 339; and communication was 91 per 100000 population. Fifty per cent of ADL, IADL, and FA disabilities were attributed to motor vehicle crashes and falls, as were 31% of sight, 19% of hearing, and 23% of communication disabilities. Conclusions: Though these estimates may be conservative, this study indicates that injury is a major cause of disability in addition to a leading cause of death in the US.     

Neural basis of generation of conclusions in elementary deduction

In everyday life, people untrained in formal logic draw simple deductive inferences from linguistic material (i.e., elementary propositional deductions). Presently, we have limited information on the brain areas implicated when such conclusions are drawn. We used event-related fMRI to identify these brain areas. A set of multiple and independent criteria was derived from the two main theories in the field of reasoning to maximize the reliability of detection of areas in which activity is specifically associated with deductive inferences. Two left lateralized clusters of areas, one in frontal cortex (Brodmann Area 44 and 6) and one in parietal lobe (BA 40), satisfied all criteria; activation was present at the moment of inference, it was shared by both conditional ("if-based") and disjunctive ("or-based") inferences but was greater for disjunctive clauses. Identification of the reasoning network was corroborated by the observation that activity in these areas was greater the longer the reasoning time. Taken together with results from preceding studies, our findings suggest possible theoretically relevant dissociations between elementary propositional deductions and other types of deductive reasoning.     

Predicting return to work after brain injury using occupational therapy assessments

Purpose: The aim of this study was to evaluate the value of occupational therapy assessments used in an outreach rehabilitation programme to predict return to work after brain injury. The assessments represent the ICIDH-2 levels of body function and activity. Method: Fifty-six persons in a late phase after brain injury who had been admitted to the rehabilitation programme during 2 years were followed up according to work status. The follow up was made at a minimum of 2 years after injury. Demographic data and scores from the occupational therapy assessments were compared for the two groups who were back to work or studies (BTW) and not back to work or studies (NBTW). Results: Assessments of memory, visual perception and apraxia separated between the two groups BTW and NBTW. Logistic regression showed that memory score in combination with data on PADL made up the best predictive model. In a subgroup with 21 persons where data on IADL were added to memory and PADL the predictive value was even stronger. Conclusions: In this study we found that occupational therapy assessments were valuable in predicting failure to return to work or studies after brain injury.     

Predicting return to work after brain injury using occupational therapy assessments

Purpose: The aim of this study was to evaluate the value of occupational therapy assessments used in an outreach rehabilitation programme to predict return to work after brain injury. The assessments represent the ICIDH-2 levels of body function and activity. Method: Fifty-six persons in a late phase after brain injury who had been admitted to the rehabilitation programme during 2 years were followed up according to work status. The follow up was made at a minimum of 2 years after injury. Demographic data and scores from the occupational therapy assessments were compared for the two groups who were back to work or studies (BTW) and not back to work or studies (NBTW). Results: Assessments of memory, visual perception and apraxia separated between the two groups BTW and NBTW. Logistic regression showed that memory score in combination with data on PADL made up the best predictive model. In a subgroup with 21 persons where data on IADL were added to memory and PADL the predictive value was even stronger. Conclusions: In this study we found that occupational therapy assessments were valuable in predicting failure to return to work or studies after brain injury.     

Factors associated with the self-care of home-dwelling elderly

The purpose of this study was to examine how functional capacity, activities of daily living (ADL), instrumental activities of daily living (IADL), life satisfaction and self-esteem are related to the self-care behaviour styles of home-dwelling elderly persons. Data were collected by qualitative interviews (self-care) and structured interviews (functional capacity, life satisfaction and self-esteem) from home-dwelling elderly persons (n=40) aged 75 or more. The persons were living in a medium-sized city in northern Finland. The qualitative data were analysed using deductive content analysis. The classification frame consisted of a theoretical classification developed in an earlier study. The categories were quantified and the relationship between the variables analysed by cross-tabulation. The persons whose self-care behaviour style was responsible, formally guided or independent carried out their daily activities without assistance from others, while those who showed abandoned self-care did not manage their daily activities without help. Life satisfaction was the highest among the formally guided persons and self-esteem among the responsible ones. Poor life satisfaction and self-esteem correlated with abandoned self-care behaviour.     

Performance of health-related quality-of-life instruments in a spinal cord injured population.

OBJECTIVE: General health-related quality-of-life (HRQoL) surveys have not been well tested in populations with spinal cord injury (SCI). This study evaluated the performance of 5 such instruments. DESIGN: A cross-sectional survey with instruments administered in random order during computer-assisted interviews. SETTING: A midwestern US veteran SCI program. SUBJECTS: One hundred eighty-three veterans with SCI ranging in age from 21 to 81 yrs (mean = 50.5). MEASURES: The Behavioral Risk Factor Surveillance System (BRFSS) HRQoL modules, the Quality of Well-Being scale (QWB), the Medical Outcomes Study Short-Form 36 and Short-Form 12 (SF-36, SF-12), and instrumental activities of daily living (IADL). RESULTS: Construct validity was supported by scores from the QWB, IADL, and physical health measures of the BRFSS and SF-36 showing greater impairment for quadriplegia than paraplegia. Similar constructs on the SF-36 and BRFSS were more strongly correlated than between the IADL and QWB; eg, correlation between the SF-36 Vitality scale and the BRFSS "Days full of energy" question was r = .789 (p < .01), whereas correlation between the IADL and QWB was r = -.454 (p < .01). Longer surveys (SF-36, QWB) were rated lower in subject acceptability. CONCLUSIONS: These instruments have potential for research use among patients with SCI. More studies are needed to explore the best use of instruments with apparently different domains.     

Predictors of instrumental activities of daily living in community-dwelling older adults

Psychiatric mental health clinicians often rely on proxy and self-report evaluations to determine the cognitive function of older adults however, performance measures have greater accuracy and predictive ability for everyday function. This study tested physical and cognitive predictors of functional abilities in fifty-one community residing older adults. We administered a computerized battery of executive function tasks, a performance-based measure of instrumental activities of daily living (IADL), and three physical function measures (grip strength, 30-second Chair Stand Test, and 8-foot Up and Go). Regression models assessed the associations of three components of executive function (updating, shifting, and inhibition) with IADLs and physical functions. Updating was a significant predictor of the Medications and Financial DAFS scores and of grip strength. Shifting also predicted grip strength. In conclusion, different executive functions predict different domains of IADL functioning. Working memory was a robust predictor of IADL functioning in older adults, especially medication management skills.     

Linguistic difficulties in children and adolescents after acquired brain injury: A retrospective study

Objective: The purpose of this study was to focus on two linguistic abilities, word retrieval (expressive language) and comprehension of vocabulary and grammar (receptive language), as well as to investigate to what extent long-term problems exist in these areas in children following traumatic brain injury. Methods: Two groups of children were studied retrospectively: twenty-four children with traumatic brain injury (TBI) and twenty-one children diagnosed with brain tumour. All children had been referred to the rehabilitation team for assessment. The children were between four and seventeen years old when assessed, with the assessments performed at least one year after the injury or brain tumour diagnosis. An established set of tests regarding word retrieval and comprehension of vocabulary and grammar was used, and the results were compared with normative test data. Results: In both clinical groups, significantly more children scored lower than the designated "normal" score than in the normative sample on tests measuring confrontation naming and phonological word retrieval. In addition, in the brain tumour group, more children demonstrated significantly lower results than normal performance on a test for semantic word retrieval. In the TBI group, significantly more children scored below the normal value on tests of word and grammatical comprehension when compared to the normative sample.Conclusions: This study confirms that word retrieval is an area of deficit in many children with acquired brain injuries one year or more after the injury occurred. The study also indicates that children with TBI may have persistent deficits in comprehension of both vocabulary and grammar.     

Describing quality of life and psychosocial outcomes after traumatic brain injury

OBJECTIVE: To describe the quality of life (QOL) and psychosocial outcomes of a sample of adults with traumatic brain injury in 50 community dwelling adults with traumatic brain injury and examine the associations among these variables. DESIGN: Cross-sectional. RESULTS: Mean QOL rating was low average. Standardized measures had acceptable internal reliability and normal distributions in this sample. Subjects had significantly lower QOL and social support, higher negative affect, and similar positive affect and spirituality compared with standardization and other nondisabled samples. They also had a significantly higher level of community integration than other traumatic brain injury samples. Regression analyses suggested that social support, community integration, and positive affect make a unique and significant contribution to the QOL variance with R of 0.492. The addition of spirituality reduced their respective unique variance, reducing positive affect to nonsignificant levels due to their high intercorrelation. CONCLUSIONS: Findings suggest that this sample experiences a wide range of QOL. Factors significantly associated with good QOL include community integration, positive affect, and social support; demographic variables had virtually no association with QOL. Evaluation of the sample's response to standardized scales not designed for a traumatic brain injury population support their use in similar QOL investigations.