Metacognitive function poststroke: a review of definition and assessment

Post-stroke lesion correlates of errors in verbal and spatial production tasks

Introduction

Traditional lateralization models assign post-stroke verbal impairments to the left hemisphere and spatial impairments to the right hemisphere. When considering error measures, this dichotomy may be too simplistic, as performance monitoring may involve domain-general and domain-specific components. Furthermore, the error-monitoring hypothesis predicts domain-incongruent specialization, with left hemisphere dominance for spatial and right hemisphere dominance for verbal errors.

Methods

We performed voxel-based lesion-behavior mapping in N = 110 acute stroke patients who completed a cognitively demanding, error-prone, five-point spatial design fluency task and a verbal word-fragment completion task.

Results

Significant associations were found between lesion location and error rates in both tasks, spatial fluency (correlation = 0.36, p < 0.001) and verbal completion (correlation = 0.31, p = 0.001). Right inferior frontal lesions correlated with errors in both tasks. In addition, left frontal white matter (WM) lesions were associated with spatial errors, whereas right frontal WM lesions were associated with verbal errors. After adjusting for demographics, the left WM cluster remained significant for spatial errors and the right WM cluster for verbal errors, while the right inferior frontal association with spatial errors was no longer significant.

Discussion

Post-stroke performance monitoring involves two distinct neural systems. One is a domain-general system, probably centered in the right inferior frontal region, that supports overall accuracy. The other is a widely distributed, reverse lateralized system, with left lesions associated with spatial accuracy and right lesions associated with verbal accuracy. This suggests that performance monitoring relies on more complex hemispheric interactions than traditional models suggest.

Metacognition impairment in stroke

Introduction

Metacognition (MC) impairment is prevalent among stroke survivors but is frequently undiagnosed and untreated. MC impairment hinders stroke survivors' ability to recognize their deficits, causing them to engage in activities that exceed their capabilities, set unrealistic performance goals and fail to use adaptive compensatory strategies. The present study will evaluate the clinical, neuropsychological and MRI correlates of MC impairment in a cohort of stroke survivors. The secondary objective is to describe the 12-month course of MC impairment.

Methods and analysis

The current study is a prospective cohort study. We will recruit 246 subjects. The project duration is 36 months. Subjects and carers will receive a detailed assessment at a research clinic at three, nine and 15 months after stroke onset (T1/T2/T3). The Chinese version of the Self-Awareness of Deficits Interview (SADI) will be completed by each subject. MC impairment is defined as any SADI subscale score of 2 or more. Potential covariate will be measured as well. Tests of executive functioning will be administered as well. Patients will be examined by MRI within 1 week after the onset of stroke. A stepwise logistic regression will be performed to assess the importance of lesions in the regions of interest. To examine neuropsychological functions in MC impairment, regression analysis of the SADI total and subscale scores will be performed using the significantly correlated neuropsychological functions as predictors. To examine the predictors of MC impairment remission, the demographic, clinical and MRI variables of remitters and non-remitters at T2/T3 will be examined by logistic regression.

Discussion

This project will be the first longitudinal study on MC impairment in stroke survivors. The results will shed light on the association between prefrontal cortex and subcortical lesions and MC impairment risk, symptom severity and outcome.

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.

Profiling self-awareness in brain injury rehabilitation: A mixed methods study

ABSTRACTImpaired self-awareness impacts outcomes for individuals with brain injury. Self-awareness is a complex construct, with little known about how its presentation differs across diagnostic groups, or how brain injury-related changes are expressed by individuals in the early phase post-brain injury. This study aims to identify differences and similarities in patterns of self-awareness between patients with different brain injury diagnoses, and provide a clinical account of how individuals with ABI describe changes to themselves arising from brain injury. This is a mixed methods retrospective cohort study involving an audit of medical files that included extraction of data from the Self-Awareness of Deficits Interview. Quantitative and qualitative techniques were used to analyse data from 173 participants. Individuals identified a range of brain injury-related impairments across domains, with greatest difficulty noted with linking impairments to functional implications and setting realistic goals. There were similarities and distinct differences in the expression of changes across diagnostic groups. Two main themes that aligned with self-awareness theory were identified from the data: 1/ Development of self-awareness; and 2/ Dimensions of self-awareness. These interrelated themes demonstrated the multifaceted nature of the clinical presentation of self-awareness, and highlight the need for an individualized approach to cognitive rehabilitation.

A dual-brain therapeutic approach using noninvasive brain stimulation based on two-person neuroscience: A perspective review

Our actions and decisions in everyday life are heavily influenced by social interactions, which are dynamic feedback loops involving actions, reactions, and internal cognitive processes between individual agents. Social interactions induce interpersonal synchrony, which occurs at different biobehavioral levels and comprises behavioral, physiological, and neurological activities. Hyperscanning-a neuroimaging technique that simultaneously measures the activity of multiple brain regions-has provided a powerful second-person neuroscience tool for investigating the phase alignment of neural processes during interactive social behavior. Neural synchronization, revealed by hyperscanning, is a phenomenon called inter-brain synchrony- a process that purportedly facilitates social interactions by prompting appropriate anticipation of and responses to each other's social behaviors during ongoing shared interactions. In this review, I explored the therapeutic dual-brain approach using noninvasive brain stimulation to target inter-brain synchrony based on second-person neuroscience to modulate social interaction. Artificially inducing synchrony between the brains is a potential adjunct technique to physiotherapy, psychotherapy, and pain treatment- which are strongly influenced by the social interaction between the therapist and patient. Dual-brain approaches to personalize stimulation parameters must consider temporal, spatial, and oscillatory factors. Multiple data fusion analysis, the assessment of inter-brain plasticity, a closed-loop system, and a brain-to-brain interface can support personalized stimulation.

Cognitive and self-regulation skills for employment among people with brain injury: A comparison of employed and non-employed people using mixed analysis

BACKGROUND

Employment for people with brain injuries is challenging, and identifying the factors that can be improved by rehabilitation and establishing appropriate intervention methods are imperative.

OBJECTIVE

To examine whether differences in cognitive functions and self-regulation skills exist between employed and non-employed people with brain injuries. In addition, we explored the self-regulation skills characteristic of employed people by qualitatively comparing them to those of non-employed people.

METHODS

Using a mixed research method, demographic data, neuropsychological tests, self-efficacy, and self-regulation skills were compared between 38 people with brain injuries (16 employed and 22 unemployed) in the community. Subsequently, self-regulation skills were assessed by the Self-Regulation Skills Interview (SRSI), and participants' responses were qualitatively compared.

RESULTS

No significant differences were observed in demographic data and neuropsychological tests, but employed people showed significantly better SRSI scores than unemployed people (p < 0.01). The qualitative analysis of the SRSI showed that employed people recognised themselves as having more specific symptoms than unemployed people. For example, they recognised the behaviour 'when having more than one errand, forgetting it', whereas non-employed people only recognised the category 'failure of prospective memory'. Furthermore, employed people reviewed their behaviour and developed ingenious coping strategies, such as 'looking back on appointments that have been made', 'writing down as soon as having a schedule', whereas unemployed people only exhibited categories such as 'writing schedules on the cell phone'.

CONCLUSIONS

Self-regulation skills, such as recognising specific symptoms and developing relevant coping strategies, are effective for gaining employment.

Prospective and Retrospective Metacognitive Abilities and Their Association with Impaired Self-awareness in Patients with Traumatic Brain Injury

Metacognitive impairment often occurs in patients with traumatic brain injury (TBI) and is associated with clinical problems. The aim of this study was to clarify the pathology of metacognitive impairment in TBI patients using a behavioral task, clinical assessment of self-awareness, and lesion-symptom mapping. Metacognitive abilities of TBI patients and healthy controls were assessed using a modified perceptual decision-making task. Self-awareness was assessed using the Patient Competency Rating Scale and the Frontal Systems Behavior Scale. The associations between estimated metacognitive abilities, self-awareness, and neuropsychological test results were examined. The correspondence between metacognitive disabilities and brain lesions was explored by ROI-based lesion-symptom mapping using structural magnetic resonance images. Overall, 25 TBI patients and 95 healthy controls were included in the analyses. Compared with that in healthy controls, the prospective metacognitive ability of TBI patients was lower, with metacognitive evaluations revealing a bias toward overestimating their abilities. Retrospective metacognitive ability showed a negative correlation with self-awareness but not with neuropsychological test results. In the lesion-symptom mapping analysis, the left pFC was associated with lower retrospective metacognitive ability. This study contributes to a better understanding of the pathology of metacognitive and self-awareness deficits in TBI patients and may explain the cause of impaired realistic goal setting and adaptive behavior in these patients.

Memory rehabilitation: restorative, specific knowledge acquisition, compensatory, and holistic approaches

Memory impairment following an acquired brain injury can negatively impact daily living and quality of life—but can be reduced by memory rehabilitation. Here, we review the literature on four approaches for memory rehabilitation and their associated strategies: (1) the restorative approach, aimed at a return to pre-morbid functioning, (2) the knowledge acquisition approach, involving training on specific information relevant to daily life, (3) the compensatory approach, targeted at improving daily functioning, and (4) the holistic approach, in which social, emotional, and behavioral deficits are addressed alongside cognitive consequences of acquired brain injury. Each memory rehabilitation approach includes specific strategies such as drill and practice (restorative), spaced retrieval (knowledge acquisition), memory aids (compensatory), or a combination of psychotherapy and cognitive strategies (holistic). Past research has demonstrated mixed support for the use of restorative strategies to improve memory function, whereas knowledge acquisition strategies show promising results on trained tasks but little generalization to untrained tasks and activities of daily living. Compensatory strategies remain widely used but require intensive training to be effectively employed. Finally, the holistic approach is becoming more widespread due to improvements in psychosocial wellbeing, yet there are considerable resource and cost requirements. Several factors can influence rehabilitation outcomes including metacognition and emotional disturbances. Considerations for future research to improve the applicability of strategies for memory rehabilitation include assessing memory impairment severity, examining memory needs in daily life, and exploring the long-term effects of memory rehabilitation.

Perspectives on Rehabilitation Using Non-invasive Brain Stimulation Based on Second-Person Neuroscience of Teaching-Learning Interactions

Recent advances in second-person neuroscience have allowed the underlying neural mechanisms involved in teaching-learning interactions to be better understood. Teaching is not merely a one-way transfer of information from teacher to student; it is a complex interaction that requires metacognitive and mentalizing skills to understand others’ intentions and integrate information regarding oneself and others. Physiotherapy involving therapists instructing patients on how to improve their motor skills is a clinical field in which teaching-learning interactions play a central role. Accumulating evidence suggests that non-invasive brain stimulation (NIBS) modulates cognitive functions; however, NIBS approaches to teaching-learning interactions are yet to be utilized in rehabilitation. In this review, I evaluate the present research into NIBS and its role in enhancing metacognitive and mentalizing abilities; I then review hyperscanning studies of teaching-learning interactions and explore the potential clinical applications of NIBS in rehabilitation. Dual-brain stimulation using NIBS has been developed based on findings of brain-to-brain synchrony in hyperscanning studies, and it is delivered simultaneously to two individuals to increase inter-brain synchronized oscillations at the stimulated frequency. Artificial induction of brain-to-brain synchrony has the potential to promote instruction-based learning. The brain-to-brain interface, which induces inter-brain synchronization by adjusting the patient’s brain activity, using NIBS, to the therapist’s brain activity, could have a positive effect on both therapist-patient interactions and rehabilitation outcomes. NIBS based on second-person neuroscience has the potential to serve as a useful addition to the current neuroscientific methods used in complementary interventions for rehabilitation.

Awareness of cognitive abilities in the execution of activities of daily living after acquired brain injury: an evaluation protocol

INTRODUCTION

One of the main limitations that can be observed after acquired brain injury (ABI) is the alteration of the awareness of the deficits that can occur in the cognitive skills necessary for performing activities of daily living (ADL). According to the Dynamic Comprehensive Model of Awareness (DCMA), consciousness is composed of offline component, which contains the information stored about characteristics of the tasks and stable beliefs about one's own capabilities and online awareness, which is activated in the context of the performance of a specific task. The main objective of this project was to generate and validate a detailed cognitive assessment protocol within the context of ADL to evaluate the components of DCMA.

METHODS AND ANALYSIS

The proposed protocol consists of two ecological tools: The Cog-Awareness ADL Scale to measure offline component and the Awareness ADL-task: Basic and Instrumental ADL performance-based test to measure online awareness. The aim is to identify the presence of cognitive deficits and anosognosia in patients with ABI within the context of everyday life activities. These two measures will be administered to a group of patients with ABI. In addition, these participants will complete another series of classic tests on anosognosia and cognitive functions in order to find the convergent validity of the two tests proposed in this protocol. The external validity of the Cog-Awareness ADL Scale and the relationships between awareness components within the same ADL domain will be also analysed.

ETHICS AND DISSEMINATION

This study was approved by the Ethics Committee of Biomedical Research of Andalusia, on 13 January /2017 (Proceeding 1/2017). All participants are required to provide written informed consent. The findings from this will be disseminated via scientific publication.

TRIAL REGISTRATION NUMBER

NCT03712839.

Renewed Perspectives on the Deep Roots and Broad Distribution of Animal Consciousness

The vast majority of neurobiologists have long abandoned the Cartesian view of non-human animals as unconscious automatons-acknowledging instead the high likelihood that mammals and birds have mental experiences akin to subjective consciousness. Several lines of evidence are now extending those limits to all vertebrates and even some invertebrates, though graded in degrees as argued originally by Darwin, correlated with the complexity of the animal's brain. A principal argument for this view is that the function of consciousness is to promote the survival of an animal-especially one actively moving about-in the face of dynamic changes and real-time contingencies. Cognitive ecologists point to the unique features of each animal's environment and the specific behavioral capabilities that different environments invoke, thereby suggesting that consciousness must take on a great variety of forms, many of which differ substantially from human subjective experience.

Impaired Self-Awareness and Denial During the Postacute Phases After Moderate to Severe Traumatic Brain Injury

While a number of empirical studies have appeared on impaired self-awareness (ISA) after traumatic brain injury (TBI) over the last 20 years, the relative role of denial (as a psychological method of coping) has typically not been addressed in these studies. We propose that this failure has limited our understanding of how ISA and denial differentially affect efforts to rehabilitate persons with TBI. In this selective review paper, we summarize early findings in the field and integrate those findings with more recent observations (i.e., 1999–2019). We believe that this synthesis of information and expert clinical opinion will inform future research on ISA and denial as well as approaches to rehabilitation for persons with TBI.

Cognitive impairment before and after intracerebral haemorrhage: a systematic review

INTRODUCTION

There is increasing interest in understanding cognitive dysfunction before and after Intracerebral haemorrhage (ICH), given the higher prevalence of dementia reported (ranging from 5 to 44%) for this stroke type. Much of the evidence to date examining cognitive impairment associated with cerebrovascular disease has tended to focus more on ischaemic stroke. The aim of this review was to identify and quantify studies that focused on cognitive dysfunction pre and post ICH.

METHODS

We conducted a systematic search using databases PubMed, Science Direct, Scopus and PsycINFO to identify studies that exclusively assessed cognitive function pre and post ICH. Studies were included in the review if used a measure of global cognition and/or a neuropsychological battery to assess cognitive function. Nineteen studies were deemed relevant for inclusion, where n = 8 studies examined cognitive impairment pre ICH and n = 11 post ICH.

RESULTS

Prevalence of cognitive impairment ranged between 9-29% for pre ICH and 14-88% for post ICH. Predictive factors identified for pre and post ICH were previous stroke, ICH volume and location and markers of cerebral amyloid angiopathy (CAA). Most common cognitive domains affected post ICH were information processing speed, executive function, memory, language and visuo-spatial abilities. Most common cognitive assessments tools were the Informant Questionnaire for Cognitive Decline in the Elderly (IQCODE) for pre-existing cognitive impairment and the Mini-Mental State Examination for global cognition post ICH and the Trail Making Test where neuropsychological tests were used.

CONCLUSION

Cognitive impairment and dementia affected almost one-third of patients, whether assessed pre or post ICH.

Elements virtual rehabilitation improves motor, cognitive, and functional outcomes in adult stroke: evidence from a randomized controlled pilot study

BACKGROUND

Virtual reality technologies show potential as effective rehabilitation tools following neuro-trauma. In particular, the Elements system, involving customized surface computing and tangible interfaces, produces strong treatment effects for upper-limb and cognitive function following traumatic brain injury. The present study evaluated the efficacy of Elements as a virtual rehabilitation approach for stroke survivors.

METHODS

Twenty-one adults (42-94 years old) with sub-acute stroke were randomized to four weeks of Elements virtual rehabilitation (three weekly 30-40 min sessions) combined with treatment as usual (conventional occupational and physiotherapy) or to treatment as usual alone. Upper-limb skill (Box and Blocks Test), cognition (Montreal Cognitive Assessment and selected CogState subtests), and everyday participation (Neurobehavioral Functioning Inventory) were examined before and after inpatient training, and one-month later.

RESULTS

Effect sizes for the experimental group (d = 1.05-2.51) were larger compared with controls (d = 0.11-0.86), with Elements training showing statistically greater improvements in motor function of the most affected hand (p = 0.008), and general intellectual status and executive function (p ≤ 0.001). Proportional recovery was two- to three-fold greater than control participants, with superior transfer to everyday motor, cognitive, and communication behaviors. All gains were maintained at follow-up.

CONCLUSION

A course of Elements virtual rehabilitation using goal-directed and exploratory upper-limb movement tasks facilitates both motor and cognitive recovery after stroke. The magnitude of training effects, maintenance of gains at follow-up, and generalization to daily activities provide compelling preliminary evidence of the power of virtual rehabilitation when applied in a targeted and principled manner.

TRIAL REGISTRATION

this pilot study was not registered.

Memory monitoring and memory control in chronic stroke patients Dissociated processes

Memory problems are common in stroke patients, although little is known about how accurately chronic stroke patients can monitor and control memory processes.

Objective

The performance of memory and metamemory in stroke patients and healthy controls were investigated, as well as dissociation between performances.

Methods

10 adults with right hemisphere lesion (mean [M] age=53.2 [SD=9.7]), 10 with left hemisphere lesion (M age=60.4 [SD=6.6]) and 20 healthy participants (M age=56.5 [SD=9.3] with no neurological disease, matched for sex, age and years of education participated in a multiple-case design study. Participants completed a metamemory experimental paradigm, as well as immediate and delayed word recall and recognition tasks.

Results

Data indicated that 10 out of the 20 patients presented significantly lower scores compared to controls, two of which had global deficits (functional association). Functional dissociations between memory monitoring (judgments of learning, JOL), control (allocation of study time) and capacity (cued-recall task) among patients were found for eight cases, suggesting these processes are independent.

Conclusion

These findings reveal stroke patients may have specific metamemory impairment and can contribute to the understanding of cognitive models of metamemory processing.

Neuropsychological testing

Neuropsychological testing is a key diagnostic tool for assessing people with dementia and mild cognitive impairment, but can also help in other neurological conditions such as Parkinson’s disease, stroke, multiple sclerosis, traumatic brain injury and epilepsy. While cognitive screening tests offer gross information, detailed neuropsychological evaluation can provide data on different cognitive domains (visuospatial function, memory, attention, executive function, language and praxis) as well as neuropsychiatric and behavioural features. We should regard neuropsychological testing as an extension of the neurological examination applied to higher order cortical function, since each cognitive domain has an anatomical substrate. Ideally, neurologists should discuss the indications and results of neuropsychological assessment with a clinical neuropsychologist. This paper summarises the rationale, indications, main features, most common tests and pitfalls in neuropsychological evaluation.

Neuropsychological Assessment of Driving Capacity

Clinicians are increasingly requested to make determinations regarding patients' driving capacity in the context of neurological injury/conditions and a growing cohort of older drivers. The capability to drive safely involves a number of cognitive, physical, and sensorimotor abilities that may be impacted by injury, illness, or substances that influence alertness. Neuropsychological measures are an important component of a multidisciplinary approach for evaluation of driving capacity. Clinicians should become familiar with measures that have the best predictive validity so they may incorporate a patient's neurocognitive strengths and weaknesses in decisions about driving ability.