Memory and executive functions correlates of self-awareness in traumatic brain injury

Identifying conflict monitoring as a specific executive component that contributes to impaired self-awareness in patients with acquired brain injury

OBJECTIVE

Impaired self-awareness (SA) after acquired brain injury (ABI) has traditionally been linked to deficits in executive functions. However, conflicting findings about this relationship have been reported in the literature. This inconsistency is probably due to the multicomponent nature of both constructs, as not all aspects of executive functions may be equally relevant to all components of self-awareness. This study explored whether offline SA (i.e. metacognitive knowledge) and online SA (i.e. error detection) relate to a less studied executive component, conflict monitoring/resolution.

METHOD

Twenty-six patients with ABI performed the Three-Conflict Cognitive Control Task (3CCT), an experimental task that allowed to measure the ability to monitor and solve three different types of conflicts (Distractors-filtering, Spatial Stroop and Simon). Measures of SA were collected: offline SA was based on self-informant discrepancy about patient's everyday functional difficulties, and online SA was based on error detection abilities during a performance-based naturalistic task (The Breakfast Conflict Task).

RESULTS

After controlling for global cognition, the conflict monitoring measure of 3CCT demonstarted incremental validity in predicting offline and online SA measured in naturalistic tasks.

CONCLUSIONS

Conflict monitoring/resolution seems to be an important component of SA. This finding contributes to further understand the relationship between executive functions and SA. In addition, conflict monitoring/resolution is an executive component that should be considered when designing assessment and intervention strategies to deal with ISA.

Attention Training following Moderate to Severe Traumatic Brain Injury in Adults: A Systematic Review

OBJECTIVE

To determine the extent and efficacy of attentional training as a form of neuropsychological rehabilitation to ameliorate attention deficits in adults with moderate to severe TBI.

DATA SOURCES

Articles published in CINAHL, Cochrane Library, PubMed, PsycINFO, Scopus, and Web of Science were searched between 17 January and 27 February 2021.

STUDY SELECTION

Two reviewers blindly assessed studies for eligibility according to the following criteria: any article evaluating the efficacy of any type of behavioral intervention that targeted attention (by means of cognitive rehabilitative, psychoeducational, or neuropsychological strategies, at either an individual or group level) in adults who had sustained a formally documented moderate-to-severe TBI.

DATA EXTRACTION

Methodological quality of each article was blindly assessed by two reviewers. Data were extracted from each study, including study type, sample size, sample characteristics, summary of intervention, measures used to assess attention, statistical outcomes and results, effect size, conclusion, and limitations.

DATA SYNTHESIS

7 314 articles were retrieved from databases, 4 325 articles remained after duplicate removal, and finally 21 articles met eligibility criteria and were included in this review. Articles represented varied methodological quality in group or single subject design. Irrespective of the heterogeneity regarding intervention types and attentional outcome measures used across the studies, overall findings suggest that attentional gains can be made in this sample, irrespective of time since injury, age, and injury severity. Further, a growing interest in technology-based interventions is frequently used and holds promise to bettering rehabilitation efforts. However, there is still limited evidence supporting the ecological validity of attentional training interventions (e.g., the transfer of treatment effects to daily activities).

CONCLUSION

This paper plays a crucial role in informing ongoing rehabilitation practices, guiding clinicians with evidence-based strategies and shaping future research directions for more effective attentional training guidelines.

Awareness through relationships in individuals undergoing rehabilitation following acquired brain injury

AIM

This cross-sectional study investigated the association between self-awareness and quality of therapeutic relationships following acquired brain injury (ABI) while controlling for the potential impact of cognitive problems. It also aimed to investigate attachment as a potential moderator.

METHOD

83 adults with ABI were recruited alongside a key member of their community neurorehabilitation team. The Scale to Assess Therapeutic Relationships (STAR) was used to measure therapeutic relationship quality and attachment was measured using the Experiences in Close Relationships - Relationship Structure (ECR-RS) questionnaire. Awareness was measured using the Patient Competency Rating Scale (PCRS) and the Mayo-Portland Adaptability Inventory (MPAI-4) provided a measure of cognitive problems. The MPAI-4 also provided an additional measure of awareness.

RESULTS

A significant association between self-awareness and therapeutic relationships was found in some regression models such that higher-quality relationships were associated with better awareness, after controlling for the impact of cognitive problems. Neither childhood parental attachment nor participants' attachment towards their rehabilitation staff were moderators.

CONCLUSION

The observed associations between awareness in clients and therapeutic relationships with rehabilitation staff may have importance for rehabilitation in this context. Results highlight the value of continuing to prioritize the therapeutic relational environment in ABI rehabilitation and research.

Implementing neuropsychological rehabilitation following severe traumatic brain injury in a low-to-middle income country: a case report

Introduction

TBI incidence and distribution are largely overrepresented in low- to middle-income countries (LMICs), such as South Africa (SA), with substantial associated human and financial costs. However, access to rehabilitation for the public is severely limited and not standard practice in SA. Given this background, studies demonstrating the successful implementation of neuropsychological rehabilitation in a LMIC setting are important. Published studies of this nature are generally lacking in this context. Further, there is a need to evaluate interventions that can be implemented at a low cost. To this end, we report on a neuropsychological rehabilitation program for an individual with severe TBI in a LMIC context, aimed at improving his capacity for activities of daily living.

Method

A 33-year-old, South African male who sustained a severe traumatic brain injury (TBI) partook in a neuropsychological intervention aimed at remediating functional deficits and enhancing independent functioning. The intervention utilised principles of Goal Management Training and external memory aids, with reliance on procedural memory and errorless learning, to target the participant's impairments in executive functioning and memory through the use of assistive technology-namely smart device applications.

Results

Data collected pre- and post-intervention on formal neuropsychological measures demonstrated no significant change in cognition. However, observational data and qualitative feedback from the participant's family indicated notable improvement in performance on everyday tasks with reduced number of errors and reduced need for external prompting whilst completing intervention tasks across sessions.

Discussion

In the context of severe TBI, neuropsychological rehabilitation can facilitate gains in independent functioning. This study provides support for the value of neurorehabilitation especially for interventions that can be rolled out at low cost and should serve as impetus for further such research in South Africa, where neuropsychological rehabilitation infrastructure and services are lacking.

Insights into social communication following traumatic brain injury sustained in older adulthood

BACKGROUND

There is a lack of evidence relating to cognitive-communication difficulties following traumatic brain injury (TBI) sustained in older adulthood. A prominent area in which post-TBI cognitive-communication difficulties manifest is at the level of social communication. An investigation of social communication focusing on comparison of those injured in older and younger adulthood is a practical starting point for age-related cognitive-communication outcome comparison.

AIMS

The overall objective of this study was to explore the social communication of individuals who sustained severe TBI in an early period of older adulthood (50-70 years) compared to younger adulthood (18-40 years), as informed by self and close other reports.

METHODS & PROCEDURES

This exploratory controlled group comparison study involved analysis of self-reported and close other reported La Trobe Communication Questionnaire data for 22 adults with severe TBI (11 older at injury; 11 younger at injury) and 22 control participants (11 older; 11 younger). TBI participants were matched for injury variables and participant groups were matched for sex, age and education.

OUTCOMES & RESULTS

The close others of the older and younger adults with TBI reported them to have significantly more frequent difficulty with social communication than the close others of age-matched control groups. Older adults with TBI reported significantly more frequent difficulty with social communication than uninjured older adults. In contrast, younger adults with TBI and uninjured younger adults reported a similar frequency of difficulty with social communication. No age-based difference in the frequency of social communication difficulty was evident when comparing the self or close other reports of older and younger adults with TBI. Awareness of social communication difficulty, as indexed by comparing self and close other perceptions, showed a different pattern across the TBI groups. The older TBI group rated themselves as having significantly less frequent social communication difficulty than was perceived by their close others. In contrast, no statistically significant difference was evident between the self and close other social communication ratings of the younger TBI group.

CONCLUSIONS AND IMPLICATIONS

Where possible clinicians need to work with close communication partners to understand the nature and degree of social communication difficulty following severe TBI. This may be especially important when working with people who sustain TBI in older adulthood if future research shows that this population have greater difficulty with self-awareness of social communication difficulty.

WHAT THIS PAPER ADDS

What is already known on the subject Cognitive-communication difficulties are a common consequence of traumatic brain injury (TBI) that can have long-term impact on everyday functioning. These challenges have primarily been investigated in individuals who sustained TBI in younger adulthood. What this paper adds to existing knowledge Individuals who sustain severe TBI in early older adulthood have a higher frequency of reported social communication difficulty to non-injured adults of a similar age, albeit they may underreport such difficulties potentially in the context of reduced self-awareness. What are the potential or actual clinical implications of this work? Social communication difficulty is an issue for people who sustain severe TBI in early older adulthood. However, a poorer overall social communication outcome in comparison to those injured in younger adulthood should not be assumed. Clinical service delivery for these challenges is most optimally delivered in a collaborative manner with the individual and their close others. Future research is required to investigate the identified trends from this study.

The Breakfast and Dressing Conflict Task: Preliminary Evidence of Its Validity to Measure Online Self-Awareness After Acquired Brain Injury

IMPORTANCE

Impaired self-awareness (SA) of deficits after an acquired brain injury (ABI) severely affects patients' independence in activities of daily living (ADLs). However, any assessment tool permits an exhaustive evaluation of SA in the context of ADLs.

OBJECTIVE

To study the validity of the Breakfast and Dressing Conflict Task (BD Conflict Task) to assess online SA (awareness of performance in the context of a given task) in patients with ABI; to study its interactions with offline SA (general awareness); and to test the validity of a simplified measure of performance monitoring, the ADL Conflict-Monitoring Index.

DESIGN

Convergent validity and correlational study.

SETTING

Research laboratory, hospitals, and homes.

PARTICIPANTS

Thirty patients with ABI and 28 neurologically healthy controls.

OUTCOMES AND MEASURES

Using the BD Conflict Task, measures of emergent awareness, self-regulation, anticipatory awareness, and self-evaluation were assessed and their convergent validity and relationship with offline SA were analyzed. The ADL Conflict-Monitoring Index was calculated, and its convergent validity was tested.

RESULTS

The online SA variables of the BD Conflict Task showed convergent validity with traditional online SA measures. Offline SA correlated with emergent and anticipatory awareness in the Breakfast Task. The ADL Conflict-Monitoring Index proved to be a valid measure of patients' performance monitoring.

CONCLUSIONS AND RELEVANCE

These preliminary findings suggest that the BD Conflict Task is a valid tool to assess online SA in patients with ABI and provide further understanding of the online SA-offline SA interaction. Furthermore, the ADL Conflict-Monitoring Index may be a valid and easy-to-use monitoring measure in clinical settings. Plain-Language Summary: Patients with acquired brain injury (ABI) and reduced awareness of their cognitive deficits face problems performing activities of daily living (ADLs) and may show signs of unsafe behaviors. Being aware of one's own abilities involves anticipating problems before starting a task, detecting and correcting errors during the task, and evaluating performance afterward. This study provides preliminary validity for the Breakfast and Dressing Conflict Task, a new tool that assesses aspects of self-awareness simultaneously in the context of familiar and significant ADLs. Furthermore, the tool simplifies the assessment of detecting and correcting errors with an easy-to-use index, making it suitable for use in clinical settings.

When stroke survivors' self-ratings are inconsistent with the ratings of others: a cohort study examining biopsychosocial factors associated with impaired self-awareness of functional abilities

Background Stroke survivors' self-ratings of functional abilities are often inconsistent with ratings assigned by others (e.g. clinicians), a phenomenon referred to as 'impaired self-awareness' (ISA). There is limited knowledge of the biopsychosocial contributors and consequences of post-stroke ISA measured across the rehabilitation journey. This multi-site cohort study explored biopsychosocial correlates of ISA during subacute rehabilitation (inpatient) and at 4 months post-discharge (community-dwelling). Methods Forty-five subacute stroke survivors participated (Age M (s.d.) =  71.5 (15.6), 56% female), and 38 were successfully followed-up. Self-assessments were compared to those of an independent rater (occupational therapist, close other) to calculate ISA at both time points. Survivors and raters completed additional cognitive, psychological and functional measures. Results Multivariate regression (multiple outcomes) identified associations between ISA during inpatient admission and poorer outcomes at follow-up, including poorer functional cognition, participation restriction, caregiver burden, and close other depression and anxiety. Regression models applied cross-sectionally, including one intended for correlated predictors, indicated associations between ISA during inpatient admission and younger age, male sex, poorer functional cognition, poorer rehabilitation engagement and less frequent use of non-productive coping (adjusted R 2  = 0.60). ISA at community follow-up was associated with poorer functional cognition and close other anxiety (adjusted R 2  = 0.66). Conclusions Associations between ISA and poorer outcomes across the rehabilitation journey highlight the clinical importance of ISA and the value of assessment and management approaches that consider the potential influence of numerous biological and psychosocial factors on ISA. Future studies should use larger sample sizes to confirm these results and determine the causal mechanisms of these relationships.

The self and self-knowledge after frontal lobe neurosurgical lesions

BACKGROUND

Evidence suggests that damage to the frontal lobes can be associated with changes in cognitive and behavioral functioning and reduced awareness that such changes have occurred. In the current study, the Cognitive Awareness Model was used as a theoretical framework to explore knowledge of the self in people with acquired frontal lesions.

METHODS

Fifteen individuals with focal frontal lobe lesions (FFL) and their nominated informants were compared with fifteen healthy matched control-informant dyads on questionnaire measures designed to assess awareness of difficulties. Questionnaires were adapted to ensure all enabled pre- and post-injury perspectives to be gained from both patient and informant, and to allow novel exploration of awareness of deficits from a third person perspective.

RESULTS

Individuals with frontal lobe lesions showed adequate awareness of their post-surgery changes, which was substantiated by their informant report. Compared to the control group, the patient group was found to acknowledge more difficulties in current functioning. Perspective-taking ability was limited with both patients and controls being comparatively unreliable in assessing how they were perceived by others.

CONCLUSION

These results demonstrate that FLL patients are engaging in more atypical behaviors compared to healthy controls, but suggest that they are aware of and acknowledge these difficulties. The importance of obtaining multiple viewpoints when examining an individual's level of awareness and the clinical implications of this are discussed.

Anosognosia in moderate-to-severe traumatic brain injury: A review of prevalence, clinical correlates, and diversity considerations

METHOD

A comprehensive search of peer-reviewed articles was conducted from September to November 2020 using Google Scholar and PubMed databases. Key terms included "anosognosia," "self-awareness," "traumatic brain injury," and variants thereof. Our search was restricted to articles published in English within the last 25 years, although a few historical articles were included due to scientific merit. Articles were chosen based on methodological quality, inclusion of solely or predominantly msevTBI sample, and relevance to the current topic.

CONCLUSIONS

Anosognosia is a multifaceted and domain-specific construct that affects the majority of those with msevTBI. It is related to TBI severity, injuries in right-hemispheric and cortical midline regions, specific aspects of executive function, psychological function, and cultural factors. We offer pragmatic advice for clinicians working with this population and discuss implications for the field regarding "best practices" of anosognosia assessment and intervention.

Efficacy of Prospective Memory Rehabilitation Plus Metacognitive Skills Training for Adults With Traumatic Brain Injury: A Randomized Controlled Trial

BACKGROUND

Prospective memory (PM) failure can limit independence and productivity following traumatic brain injury (TBI). Compensatory strategy use may ameliorate the effect of PM impairment on daily life but requires sufficient self-awareness. Metacognitive skills training (MST) can facilitate self-awareness and strategy use and may improve the efficacy of PM rehabilitation.

OBJECTIVE

To evaluate the effectiveness of compensatory strategy training (COMP) with an MST component (COMP-MST) for reducing everyday PM failure and improving psychosocial integration in adults with moderate-severe TBI, compared to COMP alone and a control condition. Secondary aims were to evaluate the effect of training on psychometric PM test scores, strategy use, self-awareness, and level of care.

METHODS

Assessor and participant-blinded randomized controlled trial with 52 participants (77% male, mean age = 39.0. SD = 13.6) allocated to 3 groups: COMP-MST, COMP, and waitlist control. Interventions were delivered over 6 weekly sessions. Measures were collected pre- and post-intervention and 3-month follow-up. Data were analyzed using unstructured linear mixed-effects modeling for repeated measures and planned contrasts between time-points for each group.

RESULTS

The models showed no significant differences between the groups on primary or secondary outcome measures. Significant pre-post intervention improvements were found for significant other's ratings of everyday PM failure for both intervention groups but not the control group, with medium to large effect sizes. Clinically relevant improvements on primary outcomes were found for participants across all 3 groups.

CONCLUSIONS

This study found no significant benefits of combining MST with COMP for improving everyday PM and psychosocial integration.

CLINICAL TRIAL REGISTRATION

Australian and New Zealand Clinical Trials Registry https://www.anzctr.org.au/ ACTRN12615000996561.

Intellectual awareness of naming abilities in people with chronic post-stroke aphasia

Anosognosia, or lack of self-awareness, is often present following neurological injury and can result in poor functional outcomes. The specific phenomenon of intellectual awareness, the knowledge that a function is impaired in oneself, has not been widely studied in post-stroke aphasia. We aim to identify behavioral and neural correlates of intellectual awareness by comparing stroke survivors' self-reports of anomia to objective naming performance and examining lesion sites. Fifty-three participants with chronic aphasia without severe comprehension deficits rated their naming ability and completed a battery of behavioral tests. We calculated the reliability and accuracy of participant self-ratings, then examined the relationship of poor intellectual awareness to speech, language, and cognitive measures. We used support vector regression lesion-symptom mapping (SVR-LSM) to determine lesion locations associated with impaired and preserved intellectual awareness. Reliability and accuracy of self-ratings varied across the participants. Poor intellectual awareness was associated with reduced performance on tasks that rely on semantics. Our SVR-LSM results demonstrated that anterior inferior frontal lesions were associated with poor awareness, while mid-superior temporal lesions were associated with preserved awareness. An anterior-posterior gradient was evident in the unthresholded lesion-symptom maps. While many people with chronic aphasia and relatively intact comprehension can accurately and reliably report the severity of their anomia, others overestimate, underestimate, or inconsistently estimate their naming abilities. Clinicians should consider this when administering self-rating scales, particularly when semantic deficits or anterior inferior frontal lesions are present. Administering self-ratings on multiple days may be useful to check the reliability of patient perceptions.

Estimating premorbid intelligence in persons with traumatic brain injury: an examination of the Test of Premorbid Functioning

Knowledge of intelligence is essential for interpreting cognitive performance following traumatic brain injury (TBI). The Test of Premorbid Functioning (ToPF), a word reading test co-normed with the Wechsler Adult Intelligence Scale 4th Edition (WAIS-IV), was examined as a tool for estimating premorbid intelligence in persons with a history of TBI. Fifty-two participants with mild, moderate, or severe TBI were administered the ToPF and WAIS-IV between two weeks and 19 months post-injury. The independent ability of the ToPF/demographic score and the Verbal Comprehension Index (VCI) to predict WAIS-IV Full Scale IQ (FSIQ) was examined, as were discrepancies between ToPF and WAIS-IV scores within and between participants. The ToPF/demographic predicted FSIQ accounted for a significant proportion of variability in actual FSIQ, above and beyond that accounted for by education or time since injury. ToPF and WAIS-IV scores did not differ by injury severity. In our sample, the ToPF/demographic predicted FSIQ underestimated intelligence in a substantial portion of our participants (31%), particularly in those with high average to superior intelligence. Finally, VCI scores were more predictive of actual FSIQ than the ToPF/demographic predicted FSIQ. The ToPF frequently underestimated post-injury intelligence and is therefore not accurately measuring premorbid intelligence in our sample, particularly in those with above average to superior intelligence. Clinicians are encouraged to administer the entire WAIS-IV, or at minimum the VCI subtests, for a more accurate measure of intelligence in those with above average intelligence and history of TBI.

Impaired self-awareness after traumatic brain injury: A systematic review. Part 2. Consequences and predictors of poor self-awareness

BACKGROUND

Impaired self-awareness (ISA) has frequently been found both frequent and deleterious in patients with moderate to severe traumatic brain injury (TBI).

OBJECTIVES

This is the second of a two-part systematic review on ISA after TBI, focusing on the consequences and predictors of ISA after TBI.

METHODS

Following the PRISMA guidelines, 95 articles meeting the inclusion criteria were included; 46 were specifically related to this second part of the review.

RESULTS

Among 16 studies that investigated the effect of ISA on outcome, most (n=13) found poor self-awareness associated with poor rehabilitation, functional, social and vocational outcome and with increased burden on relatives. Multiple factors have been found associated with increased frequency of ISA. ISA was found significantly related to injury severity in 8 of 10 studies, impaired executive functions in 12 of 15 studies, and poor social cognition in 3 studies, but paradoxically inverse associations were repeatedly found between self-awareness and emotional status (11 of 12 studies). Finally, although research in the field is still scarce, ISA seems associated with a dysfunction within brain networks involving the anterior cingulate cortex, anterior insula and fronto-parietal control network.

CONCLUSIONS

ISA is a complex and multifaceted disorder associated with poor rehabilitation outcome, severe injuries, and deficits of executive functions and social cognition but has an inverse association with mood impairments.

Awareness of deficit following traumatic brain injury: A systematic review of current methods of assessment

Background: Awareness of deficit plays an important role in adjustment following a brain injury and has been noted to impact on engagement with and outcome of rehabilitation. However, there are challenges associated with the assessment of awareness. Aim: To systematically review all instruments used to assess intellectual awareness of deficits following Traumatic Brain Injury (TBI) in adults, and evaluate instrument characteristics (e.g., the format and focus of measures of awareness) and assessment methods adopted. Results: Thirty-four studies, all rated as fair to good quality, were identified and within these twenty-three different assessment tools were adopted. The most common method of assessment was patient-proxy discrepancy, with three frequently used instruments employed in a total of 22 of the 34 studies. Across studies, variability was noted regarding the type of assessment method dependent on various sample demographics (e.g., age of sample) and injury characteristics (e.g., time post injury). Conclusions: There is no consensus on the preferred instrument to assess intellectual awareness of deficits after TBI. Continued instrument development should attempt to incorporate multiple perspectives and assessment should take into account demographic and injury-related factors. An insightful avenue for future research would be to determine which factors are likely to impact awareness measurement.

Self-awareness and underestimation of cognitive abilities in patients with adult temporal lobe epilepsy after surgical treatment

INTRODUCTION

Self-awareness of cognitive, emotional, functional, and social performance is critical for compliance with treatment. However, few studies have investigated self-awareness and the associated effects on other cognitive variables in patients with temporal lobe epilepsy (TLE) after surgical treatment.

AIM

This study was designed to investigate the prevalence of impaired self-awareness (ISA) in patients with TLE who have undergone surgical treatment. Associated correlations with clinical variables (frequency of seizures before surgery, time elapsed since the epilepsy diagnosis, depression, and anxiety) and verbal and visual episodic memory function and differences between patients with right and left TLE were also investigated.

METHOD

Twenty-three adults with TLE after surgical treatment were assessed with the Patient Competency Rating Scale (PCRS-R-BR), the Rey Auditory Verbal Learning Task (RAVLT), and the Modified Ruche Visuospatial Learning Test (RUCHE-M). Patients were considered to have memory dysfunction if delayed recall as assessed with the RUCHE-M or RAVLT was at or below the 25th percentile. Patients were considered to have ISA if PCRS-R-BR discrepancy scores were at or above the 75th percentile. Underestimated cognitive ability (UCA) was defined as a PCRS-R-BR discrepancy percentile score ≤25. Results were analyzed using frequency, Spearman correlation, regression analyses, and the Mann-Whitney test.

RESULTS

Frequency analysis of the total sample indicated ISA in 39.13% of patients (n = 9), UCA in 39.13% of patients (n = 9), and impaired verbal and/or visual memory performance in 69.56% of patients (n = 16). Moderate positive correlations were found between the frequency of seizures before surgical treatment and relatives' reports, as well as between the duration of time that had elapsed since the epilepsy diagnosis and patient reports. Negative and moderate correlations were found between the frequency of seizures and the discrepancy score, as well as between depression and patient reports. No differences in PCRS-R-BR were found between patients with right vs. left TLE. No clinical variables significantly predicted self-report or self-awareness.

CONCLUSION

Patients with TLE exhibit various patterns of ISA and negative effects on cognitive function after surgical treatment. Emotional factors and relatives' reports must be considered when assessing these patients.

Self-Awareness Moderates the Association Between Executive Dysfunction and Functional Independence After Acquired Brain Injury

OBJECTIVE

Impaired self-awareness (SA) is a common symptom after suffering acquired brain injury (ABI) which interferes with patient's rehabilitation and their functional independence. SA is associated with executive function and declarative memory, two cognitive functions that are related to participants' daily living functionality. Through this observational study, we aim to explore whether SA may play a moderator role in the relation between these two cognitive processes and functional independence.

METHOD

A sample of 69 participants with ABI completed a neuropsychological assessment focused on executive function and declarative memory which also included a measure of SA and functional independence. Two separated linear models were performed including functional independence, SA, and two neuropsychological factors (declarative memory and executive function) derived from a previous principal component analysis.

RESULTS

Moderation analysis show a significant interaction between SA and executive function, reflecting an association between lower executive functioning and poorer functional outcome, only in participants with low levels of SA. Notwithstanding, declarative memory do not show a significant interaction with SA, even though higher declarative memory scores were associated with better functional independence.

CONCLUSIONS

SA seems to play a moderator effect between executive function, but not declarative memory, and functional independence. Accordingly, participants with executive deficits and low levels of SA might benefit from receiving specific SA interventions in the first instance, which would in turn positively impact on their functional independence.

Cognitive predictors of self-awareness in patients with acquired brain injury along neuropsychological rehabilitation

Previous research has identified a critical role of executive function and memory in self-awareness, a metacognitive capacity often impaired in acquired brain injury. Through this observational study, we aimed to explore the effect of cognitive rehabilitation on the predictive value of these variables, as also whether any of them can predict the level of self-awareness once the cognitive rehabilitation is completed. 69 patients underwent a neuropsychological assessment, including self-awareness, at admission to and discharge from a cognitive rehabilitation process. Regression analysis was performed at these two moments and a third one was conducted to evaluate whether any of the variables at admission predicted the level of self-awareness at discharge. Verbal fluency was found to be the best predictor of self-awareness, both at admission and discharge. In addition, inhibition and cognitive flexibility, as well as episodic memory, appeared as significant predictors of post-rehabilitation self-awareness. Finally, verbal fluency was revealed as the unique pre-rehabilitation predictor of subsequent level of self-awareness following rehabilitation. While post-acute self-awareness is predicted by non-specific executive measures, the cognitive improvement putatively induced by neuropsychological rehabilitation reveals the contribution of more specific executive and memory functions. Importantly, pre-rehabilitation verbal fluency scores predicted the level of self-awareness after cognitive rehabilitation.

Depression, apathy and impaired self-awareness following severe traumatic brain injury: a preliminary investigation

Primary Objective: The primary aim of this study was to determine the frequency of severe impaired self-awareness (ISA) in patients with severe traumatic brain injury (TBI) and the correlates of selected clinical, neuropsychiatric and cognitive variables. The secondary aim of the study was to assess depression and apathy on the basis of their level of self-awareness. Methods: Thirty patients with severe TBI and 30 demographically matched healthy control subjects (HCs) were compared on measures of ISA, depression, anxiety, alexithymia, neuropsychiatric symptoms and cognitive flexibility. Results: Twenty percent of the patients demonstrated severe ISA. Severe post-acute ISA was associated with more severe cognitive inflexibility, despite the absence of differences in TBI severity, as evidenced by a Glasgow Coma Scale (GCS) score lower than 9 in all cases in the acute phase. Patients with severe ISA showed lower levels of depression and anxiety but tended to show more apathy and to have greater difficulty describing their emotional state than patients with severe TBI who showed minimal or no disturbance in self-awareness. Conclusion: These findings support the general hypothesis that severe ISA following severe TBI is typically not associated with depression and anxiety, but rather with apathy and cognitive inflexibility.

Improving Self-awareness After Acquired Brain Injury Leads to Enhancements in Patients’ Daily Living Functionality

Objective:

To explore whether the improvement in self-awareness induced by a structured intervention programme in patients suffering a brain injury is associated with an enhancement in their functional outcomes.

Method:

This study uses a pre- and post-test control group design with a sample of 56 patients with acquired brain injury randomly assigned to an experimental and a control group. Pre- and post-intervention measurements were self-awareness (using a previously developed scale) and functional outcome (using the Lawton Instrumental Activities of Daily Living Scale).

Results:

Patients who received the intervention programme showed a greater improvement in their self-awareness level and functional outcome than patients in the control group. Additionally, the correlation analyses between improvements at both measures showed a relation between improvement in self-awareness and improvement in functional outcome, especially when the pre-treatment self-awareness level was considered.

Conclusions:

Implementing an intervention programme in self-awareness, in the context of a global rehabilitation process of patients with acquired brain injury, is useful for improving their self-awareness level and the functionality in their daily activities.

Enriched environment improves working memory impairment of mice with traumatic brain injury by enhancing histone acetylation in the prefrontal cortex

Working memory impairment is a common cognitive dysfunction after traumatic brain injury (TBI), which severely affects the quality of life of patients. Acetylcholine is a neurotransmitter which is closely related to cognitive functions. In addition, epigenetic modifications are also related to cognitive functions. A neurorehabilitation strategy, enriched environment (EE) intervention, has been widely used to improve cognitive impairment. However, studies of the mechanism of EE on cholinergic system and epigenetic modifications in mouse with TBI have not been reported yet. In this paper, a mouse model with traumatic frontal lobe injury was established, and the mechanism on EE for the mice with TBI was explored. It was found that EE could improve Y-maze performance of mice with TBI, the function of cholinergic system, and the imbalance of acetylation homeostasis in the prefrontal cortex of contralateral side of TBI. In addition, EE also could increase the level of CREB binding protein and histones H3 acetylation at ChAT gene promoter region in the prefrontal cortex of contralateral side of TBI. These indicate that EE has an important effect on the improvement of working memory impairment and the underlying mechanism may involve in histones H3 acetylation at ChAT gene promoter regions in the prefrontal cortex.

Assessment of Patient Self-awareness and Related Neural Correlates in Frontotemporal Dementia and Corticobasal Syndrome

OBJECTIVE

We compared two different methods of assessing self-awareness (clinician-rated vs. self- and caregiver report) in participants with neurodegenerative conditions. Additionally, we examined the contribution of memory dysfunction to assessment of self-awareness.

METHOD

Sixty-seven participants with various neurodegenerative disorders participated in this study. Data were collected on brain volume, neurocognitive function, demographic characteristics, and two measures of patient self-awareness, defined as (1) the discrepancy between patient and caregiver ratings of dysexecutive syndrome and (2) clinician-observed rating of patient insight. Penalized regression with best subset variable selection and 10-fold cross-validation was used to evaluate three neurocognitive frameworks: self-regulation, language, and perspective-taking, each predicting the results from the two methods of self-awareness measurement.

RESULTS

The self-regulation framework was more robustly predictive for both the clinician rating and discrepancy method than language or perspective-taking. Frameworks in which the clinician rating was the criterion were more robust than those with the discrepancy method as criterion. When a measure of memory functioning was added to the framework, there was no appreciable improvement in the prediction of self-awareness.

CONCLUSIONS

A self-regulation neurocognitive framework, consisting of regions of interest and neuropsychological test scores, was more effective in understanding patient self-awareness than perspective-taking or language frameworks. Compared to the discrepancy method, a clinician rating of self-awareness was more robustly associated with relevant clinical variables of regional brain volume and neuropsychological performance, suggesting it may be a useful measure to aid clinical diagnosis.