Anosognosia versus unilateral neglect. Coexistence and their relations to age, stroke severity, lesion site and cognition

The effect of offline anosognosia for hemispatial neglect on neglect rehabilitation in patients with subacute and chronic right hemispheric brain injury. A retrospective cohort study

CLINICAL TRIALS REGISTRATION NUMBER

NCT05145855.

Key constructs of body awareness impairments post-stroke: a scoping review of assessment tools and interventions

PURPOSE

To summarise body awareness assessment tools and interventions relevant for stroke rehabilitation using a framework that categorises key body awareness constructs, disorders and impairments.

MATERIALS AND METHODS

Online electronic databases and trial registries were searched from inception until July 2021, in addition to hand searching reference lists of included studies and reviews. Study selection included any study design where the investigation involved assessing and/or intervening in body awareness following stroke. Data were extracted based on predefined criteria by two independent reviewers and mapped to the emergent framework.

RESULTS

The final analysis included 144 papers that reported 43 assessment tools and 8 types of interventions for body awareness. Consensus was reached on a synthesised body awareness framework. This comprised specific impairments and disorders, constructs, sub-categories and main categories leading to the overarching term of body awareness. Clinical and psychometric properties of the assessment tools were not reported or poorly evaluated, and the interventions lacked robust study designs and rigorous methods.

CONCLUSIONS

The framework produced will enable future research and clinical practice to be based on consistent concepts and definitions. Clinicians can also use this information to cautiously select assessment tools and/or interventions but are reminded of the limitations identified in this review.Implications for rehabilitationThere is limited understanding, compounded by inconsistent terminology and definitions regarding body awareness after stroke.A synthesized framework to define key constructs and definitions of body awareness is proposed.Assessment tools and interventions reported in the literature are mapped to the proposed framework.Psychometric properties of available tools are reported.Significant work remains to refine concepts of body awareness, develop and evaluate assessment tools and interventions.

Pilot Study of Mindfulness Training on the Self-Awareness of Motor Symptoms in Parkinson's Disease - A Randomized Controlled Trial

Objective: This study aims to evaluate feasibility and effects of a newly developed mindfulness intervention tailored to specific needs of patients with Parkinson’s disease (PD).

Background: The phenomenon of impaired self-awareness of motor symptoms (ISAm) in PD might be reduced by increasing patients’ mindfulness. A PD-specific mindfulness intervention has been developed and evaluated as a potential treatment option: IPSUM (“Insight into Parkinson’s Disease Symptoms by using Mindfulness”).

Methods: IPSUM’s effectiveness is evaluated by comparing an intervention with a waitlist-control group. Applying a pre-post design, patients were assessed before, directly after and 8weeks after treatment. The primary outcome was the change in a quantitative ISAm score from baseline to post-assessment. Secondary outcome measures were PD-related affective changes and neuropsychological test performance. Feasibility was evaluated via feedback forms.

Results: In total, 30 non-depressed and non-demented PD patients were included (intervention: n=14, waitlist-control: n=16). ISAm score did not change significantly, but the training group showed greater performance in sustained attention and language tasks over time. Additional changes included greater mindfulness as well as less sleeping problems and anxiety. Cognitive disturbances, apathy, and sleeping problems worsened only in the waitlist-control group. Patients’ feedback regarding the training concept and material was excellent.

Conclusion: Insight into Parkinson’s Disease Symptoms by using Mindfulness has not been capable of reducing ISAm in PD patients but appears to be a feasible and effective concept to, among others, support mental health in the mid-term. It has to be noted though that the study was stopped beforehand because of the SARS CoV-2 pandemic. The lack of findings might therefore be caused by a lack of statistical power. The need for further research to better understand the mechanisms of ISAm and its connection to mindfulness in PD is highlighted.

Comparison of mortality rate in older adults with and without functional awareness: the Neurological Disorders in Central Spain (NEDICES) population-based study

OBJECTIVES

The main aim of the study was to compare the rates of mortality in older adults with and without functional unawareness (FU). We also tested a possible interaction effect between levels of awareness and education, as a single cognitive reserve proxy, on mortality.

STUDY DESIGN

The study design is a longitudinal population-based cohort study.

METHODS

The Neurological Disorders in Central Spain is epidemiological study to detect main age-associated conditions in people aged 65 years and older. Participants were collected from updated population-based registers of residents in three areas of central Spain. Awareness of functional limitations was established in accordance with the discrepancy between two sources of information on functional impairments: reliable informants versus the participants themselves. Three mutually exclusive groups were formed, namely, Functional Limitation Complaints (FCs), FU, and Functional Awareness (FA). Cox's regression models, adjusted by different covariates, were used to calculate the risk of mortality for each group at 5-year follow-up (vs. reference group without limitations).

RESULTS

Of 1818 selected individuals, 229 (12.5%) showed FA, 254 (13.9%) showed FC, and 96 (5%) were classified as FU. All these groups showed an increased risk of mortality at 5-year follow-up [adjusted hazard ratio (HR) for FC < FU < FA]. However, the association of FU with mortality remained significant only for highly educated individuals.

CONCLUSIONS

Functional impairment was associated with increased mortality rates, regardless of the presence of unawareness. This study extends the role of education in modulating the symptoms and prognosis of individuals at very mild or preclinical dementia stages.

Improving Self-Awareness of Motor Symptoms in Patients With Parkinson's Disease by Using Mindfulness - A Study Protocol for a Randomized Controlled Trial

Objective

This study aims to increase self-awareness in patients with Parkinson’s disease (PD) using a newly developed mindfulness-based intervention, tailored for the specific needs of PD patients. Its impact on self-awareness and patients’ daily lives is currently being evaluated.

Background

Recently, the phenomenon of impaired self-awareness for motor symptoms (ISAm) and some non-motor symptoms has been described in PD. ISAm can negatively influence patients’ daily lives, e.g., by affecting therapy adherence, and is therefore the main focus of this study. The main goal is the development of IPSUM (“Insight into Parkinson’s Disease Symptoms by using Mindfulness”), a PD-specific intervention for increasing patients’ mindfulness and thereby reducing ISAm.

Methods

The effectiveness of IPSUM is evaluated by comparison of an intervention group with a waitlist-control group. A pre-post design with an additional 8-week follow-up measurement is applied, resulting in three measurement points: before, directly after and 8 weeks after completing the intervention protocol. In total, up to 180 non-depressed PD patients without severe cognitive impairment (non-demented) will be included. The primary outcome is a quantitative score for measuring ISAm. Secondary outcome measures are affective changes, neuropsychological performance and self-awareness of cognition. At pre- and post-measurement an fMRI scan is performed to connect behavioral and neurobiological findings. At post- and follow-up-measurement each patient will take part in a semi-structured interview to explore IPSUM’s impact on self-awareness and patients’ everyday lives.

Results

The conception of the intervention protocol is finished, the resulting 8-week program is presented in detail. It has successfully been tested in the first group of patients, their feedback so far was quite promising. Recruitment is ongoing and a first interim analysis will be performed once 30 patients have completed IPSUM.

Conclusion

For the first time, the intervention protocol of IPSUM has successfully been tested in a group of PD patients. As the study goes on, more quantitative data is collected for statistical analyses to evaluate its effectiveness. More qualitative data is collected to evaluate feasibility and effectiveness. We hope for this intervention to be capable of reducing the patients’ ISAm and improving their quality of life on many levels.

Anosognosia for limb and bucco-facial apraxia as inferred from the recognition of gestural errors

Anosognosia is a multifaceted syndrome characterized by a lack of awareness of motor, cognitive, or emotional deficits. While most studies have focused on basic motor disorders such as hemiplegia, only recently, the issue of whether anosognosia also concerns higher-order motor disorders like apraxia has been addressed. Here, we explore the existence of a specific form of anosognosia for apraxia in forty patients with uni-hemispheric vascular lesions. The patients were requested to imitate actions involving upper limb or bucco-facial body parts and then judge their performance. Successively, they were also asked to observe video recordings of the same actions performed by themselves or by other patients and judge the accuracy of the displayed actions. The comparison of participants versus examiner judgement and between error recognition of others' versus self's actions was considered as an index of awareness deficit for the online and offline conditions, respectively. Evidence was found that awareness deficits occurred both immediately after action execution (online anosognosia) and in the video recording task (offline anosognosia). Moreover, bucco-facial and limb apraxic patients were specifically unaware of their errors in bucco-facial and limb actions, respectively, indicating for the first time a topographical organization of the syndrome. Our approach allowed us to distinguish awareness deficits from more general disorders in error recognition; indeed, anosognosic patients were able to identify errors when the same action was executed by another patient but not when the video showed their own actions. Finally, we provide evidence that anosognosia for apraxia might be associated with frontal cortical and subcortical networks.

Hippocampal diaschisis contributes to anosognosia for hemiplegia: Evidence from lesion network-symptom-mapping

Anosognosia for hemiplegia (AHP) is known to be associated with lesions to the motor system combined with varying lesions to the right insula, premotor cortex, parietal lobe or hippocampus. Due to this widespread cortical lesion distribution, AHP can be understood best as a network disorder. We used lesion maps and behavioral data (n ​= ​49) from two previous studies on AHP and performed a lesion network-symptom-mapping (LNSM) analysis. This new approach permits the identification of relationships between behavior and regions connected to the lesion site based on normative functional connectome data. In a first step, using ordinary voxel-based lesion-symptom mapping, we found an association of AHP with lesions in the right posterior insula. This is in accordance with previous studies. Applying LNSM, we were able to additionally identify a region in the right posterior hippocampus where AHP was associated with significantly higher normative lesion connectivity. Notably, this region was spared by infarction in all patients. We therefore argue that remote neuronal dysfunction caused by disrupted functional connections between the lesion site and the hippocampus (i.e. diaschisis) contributed to the phenotype of AHP. An indirect affection of the hippocampus may lead to memory deficits which, in turn, impair the stable encoding of updated beliefs on the bodily state thus contributing to the multifactorial phenomenon of AHP.

Unawareness for Motor Impairment and Distorted Perception of Task Difficulty

OBJECTIVES

Anosognosia for motor impairment is a complex syndrome that can manifest itself under different forms, guiding patients' behavior and task decisions. However, current diagnostic tools tend to evaluate only more explicit aspects of anosognosia (asking the patients about their motor abilities) and fail to address more subtle features of awareness. We have developed a new assessment measure, the ECT (Errand Choice Test), where patients are asked to judge task difficulty rather than estimate their own impairment.

METHODS

We assessed awareness in a group of 73 unilateral left- and right-brain damaged (30 LBD and 43 RBD, respectively) patients by means of the VATAm, which explicitly requires them to evaluate their own motor abilities, and the ECT. A control group of 65 healthy volunteers was asked to perform the ECT under two conditions: Current condition (i.e., using both hands) and Simulated conditions (i.e., simulating hemiplegia).

RESULTS

A total of 27% of the patients showed different performance on the VATAm and ECT, 21% of the patients showing lack of awareness only on VATAm and 6% only on ECT. Moreover, despite the ECT identified a higher frequency of anosognosia after RBD (33.3%) than LBD (27.6%), this hemispheric asymmetry was not significant. Remarkably, anosognosic patients performed very similarly to controls in the "current condition", suggesting that anosognosic patients' ability to perceive the complexity of each task per se is not altered.

CONCLUSION

Different methods may be able to tackle different aspects of awareness and the ECT proved to be able to detect less evident forms of awareness. (JINS, 2018, 24, 45-56).

Examining Anosognosia of Neglect

Unilateral neglect (neglect) and anosognosia often co-occur post stroke. It is unknown whether anosognosia of neglect varies for different types of daily activities. The objective is to examine the frequency of anosognosia of neglect for items on the Catherine Bergego Scale (CBS) and to determine the level of agreement between participant/assessor item ratings and total scores. Secondary analysis of data was carried out. We conducted descriptive analyses and interrater reliability analyses (Cohen's kappa) to determine the level of agreement between assessor and participant item ratings. A paired t test was conducted to compare assessor and participant total scores. The frequency of anosognosia among items varied (29.2%-83.3%) and Kappa statistics ranged from -0.07 (no agreement) to 0.23 (fair agreement) for item ratings. There was a significant difference- t(36) = 3.02, p ≤ .01)-between assessor ( M = 8.0, SD = 5.2) and participant-rated ( M = 5.3, SD = 4.5) total CBS scores. Anosognosia is prevalent among those with neglect. Findings highlight the importance of assessing for anosognosia.

What are the functional outcomes of right hemisphere stroke patients with or without hemi-inattention complications? A critical narrative review and suggestions for further research

Purpose: There is widespread acceptance that patients demonstrating neglect/hemi-inattention (HI) following right hemisphere stroke (RHS) underachieve functionally compared to their counterparts without neglect. However, empirical evidence for this view needs examination. The purpose of this review is to critically appraise relevant studies that compared outcomes from RHS patients with/without hemi-attention and suggest more robust follow-up research. Method: Twelve studies published in 1995–2013 were critically reviewed. Two independent reviewers appraised design features including sample representation, assessment and data analysis methods. Strengths and limitations were highlighted. Results: Results were largely inconsistent. Considerable heterogeneity within patient groups and across studies complicated interpretation. Evidence suggested average group disparity in scores between patients with and without HI at discharge but the cause of functional disparity could not be attributed specifically to HI from the data and modelling results available. Conclusion: The relationship between HI status and functional recovery warrants further investigation in studies with stronger methodology to ensure rigour and robustness in the results. Pending further research, HI status should not be regarded as a key predictor of functional recovery or rehabilitation potential in patients with RHSs. This group should continue to receive appropriate therapeutic intervention aimed at maximising their functional recovery post-stroke.

Implications for Rehabilitation

Findings from this review demonstrate a paucity of evidence to support the presence of hemi-inattention as a key predictor of functional recovery in patients with right hemisphere stroke; as such, practitioners should take this into consideration when planning rehabilitation programmes of their patients.

In the initial months following right hemisphere stroke, there are wide-ranging differences in the rate and amount of functional recovery in patients, with and without hemi-inattention. Practitioners should not limit the aspirations of their patients based on the presence or absence of hemi-inattention.

This review has identified a number of measurement limitations in commonly employed assessment tools for hemi-inattention and overall functional recovery. As such, practitioners should take the limitations of specific measures into account when interpreting the results contextually and with respect to their patients’ situation.

Development and psychometric evaluation of a scale to measure impaired self-awareness of hyper- and hypokinetic movements in Parkinson's disease

OBJECTIVE

Patients with Parkinson's disease (PD) can show impaired self-awareness of motor deficits (ISAm). We developed a new scale that measures ISAm severity of hyper- and hypokinetic movements in PD during medication on state and defined its psychometric criteria.

METHOD

Included were 104 right-handed, non-depressed, non-demented patients. Concerning ISAm, 38 motor symptoms were assessed using seven tasks, which were performed and self-rated concerning presence of deficit (yes/no) by all patients. The whole procedure was videotaped. Motor symptoms were then evaluated by two independent experts, blinded for patient's ratings, concerning presence, awareness of deficit, and severity. Exploratory principal component analysis (promax rotation) was applied to reduce items. Principal axis factoring was conducted to extract factors. Reliability was examined regarding internal consistency, split-half reliability, and interrater reliability. Validity was verified by applying two additional measures of ISAm.

RESULTS

Of the initial 38 symptoms, 15 remained, assessed in five motor tasks and merged to a total severity score. Factor analysis resulted in a four factor solution (dyskinesia, resting tremor right hand, resting tremor left hand, bradykinesia). For all subscales and the total score, measures of reliability (values 0.64-0.89) and validity (effect sizes>0.3) were satisfactory. Descriptive results showed that 66% of patients had signs of ISAm (median 2, range 0-15), with ISAm being most distinct for dyskinesia.

CONCLUSIONS

We provide the first validation of a test for ISAm in PD. Using this instrument, future studies can further analyze the pathophysiology of ISAm, the psychosocial sequelae, therapeutic strategies and compliance with therapy.

Hearing and music in unilateral spatial neglect neuro-rehabilitation

Unilateral spatial neglect (USN) is an attention deficit in the contralesional side of space which occurs after a cerebral stroke, mainly located in the right hemisphere. USN patients are disabled in all daily activities. USN is an important negative prognostic factor of functional recovery and of socio-professional reinsertion. Thus, patient rehabilitation is a major challenge. As this deficit has been described in many sensory modalities (including hearing), many sensory and poly-sensory rehabilitation methods have been proposed to USN patients. They are mainly based on visual, tactile modalities and on motor abilities. However, these methods appear to be quite task-specific and difficult to transfer to functional activities. Very few studies have focused on the hearing modality and even fewer studies have been conducted in music as a way of improving spatial attention. Therefore, more research on such retraining needs is neccessary in order to make reliable conclusions on its efficiency in long-term rehabilitation. Nevertheless, some evidence suggests that music could be a promising tool to enhance spatial attention and to rehabilitate USN patients. In fact, music is a material closely linked to space, involving common anatomical and functional networks. The present paper aims firstly at briefly reviewing the different procedures of sensory retraining proposed in USN, including auditory retraining, and their limits. Secondly, it aims to present the recent scientific evidence that makes music a good candidate for USN patients’ neuro-rehabilitation.

Rastreio cognitivo em pacientes com acidente vascular cerebral: um estudo transversal

Objetivo O estudo objetivou-se a fazer um rastreio cognitivo nos pacientes com acidente vascular cerebral (AVC), a fim de determinar pontos de corte de acordo com a idade, escolaridade e grau de comprometimento neurológico. Métodos Foi realizado um estudo transversal no qual participaram 109 pacientes ambulatoriais, sendo 61 homens, com média da idade de 59 anos (± 11), média do tempo de escolaridade de 5 anos (± 4) e do tempo de sequela de 16 meses (± 14). Os pacientes foram avaliados por meio do Miniexame do Estado Mental (MEEM) e pela National Institute of Health Stroke Scale. Os dados foram analisados pela regressão linear múltipla (stepwise forward). Resultados Verificou-se que as variáveis grau de comprometimento neurológico, idade e escolaridade contribuíram significativamente para o valor global do MEEM e explicaram a variância do estado cognitivo (R2 ajustado = 0,24). Cada aumento do comprometimento neurológico representou diminuição de 0,456 no escore do MEEM. Quanto maior a idade, ocorreu uma diminuição de 0,202 no MEEM, e à medida que diminui o tempo de escolaridade, houve uma diminuição de 0,190 no MEEM. Os pontos de corte variaram de 14 a 22 de acordo com o grau de comprometimento neurológico, idade e escolaridade. Conclusão Os resultados apontaram que, por meio do rastreio positivo de déficit cognitivo, foram encontrados pontos de corte associados ao comprometimento neurológico, necessitando também serem ajustados pela idade e escolaridade, sugerindo que essas associações sejam preferencialmente levadas em consideração na planificação da reabilitação neuropsicológica dos pacientes com AVC.

The Neural Basis of Anosognosia for Spatial Neglect After Stroke

Background and Purpose—

The present study investigated the lesion anatomy of anosognosia for visuospatial neglect resulting from right hemispheric stroke.

Methods—

In 63 patients, self-ratings of performance in paper-and-pencil tests were contrasted with external performance ratings. Lesion analysis was conducted on patient subgroups with different degrees of anosognosia but comparable visuospatial impairment.

Results—

Independent of the severity of visuospatial neglect per se, damage to the right angular and superior temporal gyrus was associated with higher levels of anosognosia.

Conclusions—

Using a novel assessment of anosognosia for spatial neglect, the present study relates stroke-induced self-awareness deficits to inferior parietal and superior temporal brain damage.

VATA-L: visual-analogue test assessing anosognosia for language impairment

Lack of awareness (anosognosia) for one's own language impairments has rarely been investigated, despite hampering language rehabilitation. Assessment of anosognosia by means of self-report is particularly complex, as a patient's language difficulties may seriously prevent or bias the assessment. Other methods, such as measures of self-correction and error detection, have provided valuable information, although they are an indirect form of assessment of anosognosia and are not exempt from methodological criticisms. In this study we report on a new tool, the VATA-L (Visual-Analogue Test for Anosognosia for Language impairment), geared at assessing explicit anosognosia for aphasia. The VATA-L compares the patient's self-evaluation with caregivers' evaluations of the patient's verbal communication abilities in a series of common situations. By means of non-verbal support and a system of check questions, this test minimizes some of the methodological limitations of existing diagnostic tools (e.g., structured interviews), enhancing reliability, and enabling assessment of patients with aphasia. Finally, normative data provided in the study allow a clearer interpretation of the patient's performance and facilitate assessment of anosognosia.

Predictors and assessment of cognitive dysfunction resulting from ischaemic stroke

Stroke remains a primary cause of morbidity throughout the world mainly because of its effect on cognition. Individuals can recover from physical disability resulting from stroke, but might be unable to return to their previous occupations or independent life because of cognitive impairments. Cognitive dysfunction ranges from focal deficits, resulting directly from an area of infarction or from hypoperfusion in adjacent tissue, to more global cognitive dysfunction. Global dysfunction is likely to be related to other underlying subclinical cerebrovascular disease, such as white-matter disease or subclinical infarcts. Study of cognitive dysfunction after stroke is complicated by varying definitions and lack of measurement of cognition before stroke. Additionally, stroke can affect white-matter connectivity, so newer imaging techniques, such as diffusion-tensor imaging and magnetisation transfer imaging, that can be used to assess this subclinical injury are important tools in the assessment of cognitive dysfunction after stroke. As research is increasingly focused on the role of preventable risk factors in the development of dementia, the role of stroke in the development of cognitive impairment and dementia could be another target for prevention.

The frequency, clinical correlates, and mechanism of anosognosia after stroke

OBJECTIVE

To review the frequency, clinical correlates, and mechanism of anosognosia after stroke.

METHODS

We searched the most recent relevant literature on anosognosia after stroke and carried out a critical analysis of the main findings.

RESULTS

Anosognosia is present in about 10% of acute stroke patients and its diagnosis is relatively simple. Nevertheless, a valid and reliable standardization of diagnostic instruments and criteria for research purposes is more difficult to achieve. This limitation may partially account for various instruments available to assess anosognosia and the different strategies used to diagnose this phenomenon. Anosognosia is a fleeting phenomenon and chronic cases are infrequent. There is a robust association between anosognosia and right-hemisphere lesions involving cortical (insular, temporal, and parietal lobes) and subcortical structures (thalamus and basal ganglia). The main clinical correlates of anosognosia are the presence of neglect, cognitive deficits, previous strokes, and older age. Anosognosia has a negative impact on the rehabilitation of stroke patients. The mechanism of anosognosia remains unknown but was explained as owing to psychological denial, disconnection between left and right hemispheres, and dysfunction of a system that monitors the intention to move and actual movements.

CONCLUSION

Anosognosia is a relatively frequent complication of acute stroke and may become an excellent model to understand the mechanism of human awareness.

A parietal-premotor network for movement intention and motor awareness

It is commonly assumed that we are conscious of our movements mainly because we can sense ourselves moving as ongoing peripheral information coming from our muscles and retina reaches the brain. Recent evidence, however, suggests that, contrary to common beliefs, conscious intention to move is independent of movement execution per se. We propose that during movement execution it is our initial intentions that we are mainly aware of. Furthermore, the experience of moving as a conscious act is associated with increased activity in a specific brain region: the posterior parietal cortex. We speculate that movement intention and awareness are generated and monitored in this region. We put forward a general framework of the cognitive and neural processes involved in movement intention and motor awareness.

Chronic unilateral neglect from focal meningoencephalitis lesions in an immune-compromised hemodialysis patient

Unilateral neglect (UN) is a disorder associated primarily with right-brain damage; it causes individuals to behave as if the contralesional half of their world has become unimportant or has simply ceased to exist. This is the first known case study to describe and measure UN caused by an infectious process, meningoencephalitis. The patient was immune compromised as a result of antirejection drugs following a kidney and pancreas transplant, as well as from a baseline vulnerability common to patients with hemodialysis. She was reassessed serially during hemodialysis treatments over 12 months and demonstrated improvement in some measures of UN but not in others. UN is a recognized nursing diagnosis and can be assessed, treated, and researched by nurses. Neuroscience nurses need to better understand and investigate UN to improve their own practice and the practice of other specialties.

Unilateral neglect is more severe and common in older patients with right hemispheric stroke

INTRODUCTION

Unilateral neglect after acute right hemispheric stroke significantly impedes poststroke recovery. We studied patients with right hemispheric stroke to determine whether increasing age was associated with more frequent or more severe neglect.

METHODS

Eight neglect tests within 5 days of symptom onset (and within 24 hours of admission) were administered to 204 subjects with acute right hemispheric stroke. Size of infarct was measured, and neglect tests were scored as percent error. "Any neglect" was defined by an elevated neglect test score, standardized relative to a group of normal controls.

RESULTS

When tested for neglect soon after acute stroke admission, 69.6% of subjects older than 65 years had "any neglect" (defined by comparison to a group of normal controls), compared with 49.4% of subjects aged 65 years and younger (p = 0.008). For every additional 10 years of age, patients were 1.83 times as likely to have neglect, even after adjusting for diffusion-weighted imaging (DWI) infarct volume and NIH Stroke Scale (NIHSS) score (95% CI 1.38-2.43). In addition, DWI volume and NIHSS independently predicted neglect. Score on virtually all of the neglect tests worsened as an effect of age. Percentage error on a line cancellation task was 3.8% higher for every additional 10 years of age, after adjustment for DWI volume and NIHSS (p = 0.006). Similar results were found for other neglect tests.

CONCLUSIONS

Increasing age in patients with acute right hemispheric stroke significantly increases the odds of unilateral neglect as well as severity of neglect, independently of size of the stroke or NIH Stroke Scale score. The reason for this finding in older patients may be because they have more brain atrophy and may be less able to compensate for cerebral infarction, or because they tend to have more cardioembolic strokes, which may be more cortically based.

Unawareness of illness in neuropsychiatric disorders: phenomenological certainty versus etiopathogenic vagueness

Awareness of illness is a form of self-knowledge concerning information about the pathological state, its functional consequence, and the way it affects the patient and his interaction with the environment. Unawareness of illness has raised much interest for its consequences on compliance with treatment, prognosis, and the patient's quality of life. This review highlights the great complexity of this phenomenon both at phenomenological and etiopathogenic levels in stroke, traumatic brain injury, psychosis, dementias, and mood disorders. In particular, the clinical expression is characterized by failure to acknowledge being ill, misattribution of symptoms, and noncompliance with treatment. Unawareness of illness may also be linked with characteristics that are peculiar to each individual disturbance, such as symptom duration and cognitive impairment. Despite a long-lasting interest in the clinical characteristics of unawareness, only recently has the focus of research investigated pathogenic mechanisms, with sometimes controversial results. The vast majority of studies have pointed out a remarkable involvement of the right hemisphere. Specifically, functional and structural changes of the dorso-lateral prefrontal cortex and some other frontal areas have often been found to be associated with awareness deficit, as well as parieto-temporal areas and the thalamus, although to a lesser extent. These data indicate the present difficulty of localizing a specific cerebral area involved in unawareness and suggest the existence of possible brain circuits responsible for awareness. In conclusion, phenomenological manifestations of poor awareness are well outlined in their complexity, whereas neuroanatomic and neuropsychological findings are still too vague and sparse and need further, greater efforts to be clarified.