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Frontiers of Neurology and Neuroscience 2019Even if Babinski (1914) is usually considered as the discoverer of anosognosia, other authors before him contributed to the development of this construct. Von Monakow... (Review)
Review
Even if Babinski (1914) is usually considered as the discoverer of anosognosia, other authors before him contributed to the development of this construct. Von Monakow (1885) and Dejerine and Vialet (1893) gave the first descriptions of patients with cortical blindness who were unaware of their disability, but did not distinguish this unawareness from the rest of the clinical description. Anton (1999) described patients with cortical deafness and cortical blindness, considering these defects of awareness as a symptom independent from the neurological dysfunction. He conceptualized them as a phenomenon in its own right and tried to link this unawareness of a disability with specific neuro-anatomical changes. Finally, Babinski (1914) coined the term "anosognosia" to designate the clinical entity conceptualized by Anton (1899) and extended this concept from the unawareness of cortical deafness and blindness to the unawareness of hemiplegia. The choice of the term "anosognosia" to denote the observed phenomenon was important, because referring to "lack of knowledge of the disease" (anosognosia), he not only emphasized the separation between "lack of knowledge" and "disease, " but also suggested a general use of this term, because disease can refer to many other disabilities besides hemiplegia. Further investigations have shown that: (a) brain-damaged patients may be unaware of different kinds of disabilities; (b) anosognosia can be selective, in that an affected person with multiple impairments may be unaware of only one handicap, while appearing fully aware of any others; and (c) lack of acknowledgment of a disease may not necessarily be due to a defective awareness, but must sometimes be considered as an extreme but understable pattern of adaptation to stress. For this condition, the term "Denial of Illness" seems preferable to that of anosognosia. Anosognosia must perhaps be viewed as a multifaceted phenomenon, resulting from both cognitive and motivational factors.
Topics: Agnosia; Awareness; Hemiplegia; History, 19th Century; History, 20th Century; Humans; Neurology; Stroke
PubMed: 31220837
DOI: 10.1159/000494954 -
Current Neurology and Neuroscience... Sep 2016Progressive decline in memory (and other functions) is the defining feature of late-life dementia but affected individuals are often unaware of this impairment. This... (Review)
Review
Progressive decline in memory (and other functions) is the defining feature of late-life dementia but affected individuals are often unaware of this impairment. This article reviews recent research on anosognosia in dementia, including methods of assessing anosognosia, its prevalence and developmental course in dementia, its occurrence in different forms of dementia, neuroimaging findings, and hypothesized component mechanisms. The results suggest that anosognosia is eventually exhibited by nearly all persons with dementia. Its occurrence is robustly associated with common dementia-related pathologies and damage to memory and self-referential brain networks and their interconnections.
Topics: Agnosia; Awareness; Dementia; Humans; Memory; Neuropsychological Tests
PubMed: 27438597
DOI: 10.1007/s11910-016-0684-z -
Continuum (Minneapolis, Minn.) Dec 2021Up to 80% of survivors of right brain stroke leave acute care without being diagnosed with a major invisible disability. Studies indicate that a generic cognitive... (Review)
Review
PURPOSE OF REVIEW
Up to 80% of survivors of right brain stroke leave acute care without being diagnosed with a major invisible disability. Studies indicate that a generic cognitive neurologic evaluation does not reliably detect spatial neglect, nor does it identify unawareness of deficit after right brain stroke; this article reviews the symptoms, clinical presentation, and management of these two cognitive disorders occurring after right brain stroke.
RECENT FINDINGS
Stroke and occupational therapy practice guidelines stress a quality standard for spatial neglect assessment and treatment to reduce adverse outcomes for patients, their families, and society. Neurologists may attribute poor outcomes associated with spatial neglect to stroke severity. However, people with spatial neglect are half as likely to return to home and community, have one-third the community mobility, and require 3 times as much caregiver supervision compared with similar stroke survivors. Multiple randomized trials support a feasible first-line rehabilitation approach for spatial neglect: prism adaptation therapy; more than 20 studies reported that this treatment improves daily life independence. Evidence-based treatment of anosognosia is not as developed; however, treatment for this problem is also available.
SUMMARY
This article guides neurologists' assessment of right brain cognitive disorders and describes how to efficiently assemble and direct a treatment team to address spatial neglect and unawareness of deficit.
Topics: Agnosia; Brain; Humans; Perceptual Disorders; Stroke; Stroke Rehabilitation
PubMed: 34881729
DOI: 10.1212/CON.0000000000001076 -
Psychogeriatrics : the Official Journal... May 2020Alzheimer's disease (AD) is a neurodegenerative disease characterised by neurocognitive impairments, especially memory impairment, as core symptoms linked to reductions... (Review)
Review
Alzheimer's disease (AD) is a neurodegenerative disease characterised by neurocognitive impairments, especially memory impairment, as core symptoms linked to reductions in activities of daily life. As marginal symptoms, neuropsychiatric symptoms (NPSs) appear during the progressive course of the disease. A lack of self-awareness (anosognosia) of cognitive and functional impairments is often seen in patients with AD, and associations between anosognosia and other NPSs have been previously reported. To account for anosognosia pathogenesis neurocognitively, the cognitive awareness model (CAM) has been helpful for explaining the stream of events from sensory input to behavioural/affective and metacognitive outputs. According to CAM, there are three types of anosognosia: (i) primary anosognosia, (ii) executive anosognosia, and (iii) mnemonic anosognosia. These types of anosognosia are generated from different neurocognitive modulations leading to metacognitive outputs or behavioural/affective regulations. Primary anosognosia is considered to be caused by deficits in the metacognitive awareness system (MAS). While preserved MAS function is associated with milder depression and anxiety in AD, a severer depressive mood in patients with mild AD can inversely cause self-underestimation. The modulation of executive anosognosia is thought to be associated with dangerous/disinhibition behaviours and apathy among NPS sub-symptoms, via impairments of comparator mechanism (Cm) within the central executive system. Other neurobehavioral reactions linked to self-awareness include 'denying' and 'confabulation', and each of these reactions is thought to be affected by the MAS and a Cm. Denial of one's own memory impairments appears as a defensive reaction to protect against dysphoric feelings, and the confabulatory comment is instantly reaction constructed by fabrications according to misinterpretations of memory information about oneself. Similarly, the innovative development of a theoretical model (CAM) has contributed to explaining the mechanism of anosognosia and some neurobehavioral outputs from a neurocognitive perspective.
Topics: Aged; Agnosia; Alzheimer Disease; Awareness; Cognitive Dysfunction; Depression; Depressive Disorder; Humans; Memory Disorders; Neurodegenerative Diseases; Neuropsychological Tests
PubMed: 31930617
DOI: 10.1111/psyg.12507 -
Rehabilitation Nursing : the Official... 2020
Review
Topics: Aged; Agnosia; Female; Hemiplegia; Humans; Male; Stroke
PubMed: 31876873
DOI: 10.1097/RNJ.0000000000000247 -
The Clinical Neuropsychologist Nov 2022A comprehensive search of peer-reviewed articles was conducted from September to November 2020 using Google Scholar and PubMed databases. Key terms included... (Review)
Review
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.
Topics: Humans; Prevalence; Neuropsychological Tests; Agnosia; Brain Injuries, Traumatic; Executive Function
PubMed: 34429014
DOI: 10.1080/13854046.2021.1967452 -
Neurocase Jun 2011Patients with neurological disorders are often partially or completely unaware of the deficits caused by their disease. This impairment is referred to as anosognosia,... (Review)
Review
Patients with neurological disorders are often partially or completely unaware of the deficits caused by their disease. This impairment is referred to as anosognosia, and it is very common in neurodegenerative disease, particularly in frontotemporal dementia. Anosognosia has significant impacts on function and quality of life for patients with neurodegenerative disease and their caregivers, but the phenomenon has received little formal study, especially in non-Alzheimer's (non-AD) dementias. Furthermore, few studies have attempted to systematically verify the potential role of specific cognitive impairments in producing anosognosia. As a result, the mechanisms underlying this phenomenon are poorly understood. Episodic memory likely plays an important role. In addition, the frontal lobe systems are important for intact self-awareness, but the most relevant frontal functions have not been identified. Motivation required to engage in self-monitoring and emotional activation marking errors as significant are often-overlooked aspects of performance monitoring that may underlie anosognosia in some patients. The present review offers a working model that incorporates these functions and stipulates specific processes that may be important for awareness of changes in one's abilities. Specification of the specific processes whose potential failure results in anosognosia can establish a roadmap for future studies.
Topics: Agnosia; Caregivers; Dementia; Frontal Lobe; Humans; Neurodegenerative Diseases; Neuropsychological Tests; Self Concept
PubMed: 21667396
DOI: 10.1080/13554794.2010.522588 -
Cortex; a Journal Devoted To the Study... Jun 2018
Topics: Agnosia; Humans; Neuropsychological Tests
PubMed: 29731103
DOI: 10.1016/j.cortex.2018.04.001 -
Cortex; a Journal Devoted To the Study... Dec 2014Anosognosia is present in a large proportion of patients with mild Alzheimer's disease (AD), and its frequency increases with the progression of the illness. Several... (Review)
Review
Anosognosia is present in a large proportion of patients with mild Alzheimer's disease (AD), and its frequency increases with the progression of the illness. Several instruments have been validated to assess anosognosia in AD, but there is no consensus regarding the best diagnostic strategy. Anosognosia in AD is a significant predictor of apathy and is significantly related to lower depression and anxiety scores, more severe caregiver burden and dangerous behaviours. Studies using different imaging modalities have demonstrated an association between anosognosia and dysfunction in frontal, temporomedial and temporoparietal regions. The mechanism of anosognosia remains unknown, but it has been explained as a consequence of deficits of encoding and updating biographical memory, and dysfunction of comparator, executive and metacognitive systems.
Topics: Agnosia; Alzheimer Disease; Apathy; Depression; Diagnosis, Differential; Humans; Memory
PubMed: 25481465
DOI: 10.1016/j.cortex.2014.07.019 -
Australasian Psychiatry : Bulletin of... Jun 2021To remind the clinical and legal practitioner that anosognosia is a recognised facet of schizophrenia with implications for capacity assessment and for relating...
OBJECTIVE
To remind the clinical and legal practitioner that anosognosia is a recognised facet of schizophrenia with implications for capacity assessment and for relating effectively with people who experience it.
CONCLUSIONS
The term anosognosia emphasises that, in schizophrenia, lack of capacity is the result of a neurological deficit. Under-appreciation of this may place that person at risk of a preventable harm.
Topics: Agnosia; Awareness; Humans; Schizophrenia
PubMed: 32469641
DOI: 10.1177/1039856220928866