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Neuropsychologia Aug 2016Developmental prosopagnosia has received increased attention in recent years, but as yet has no confirmed genetic or structural markers. It is not certain whether this... (Review)
Review
Developmental prosopagnosia has received increased attention in recent years, but as yet has no confirmed genetic or structural markers. It is not certain whether this condition reflects simply the low-end of the spectrum of normal face recognition, an 'under-development', or a pathologic failure to develop such mechanisms, a 'mal-development'. This difference in views creates challenges for the diagnosis of developmental prosopagnosia by behavioural criteria alone, which also vary substantially between studies, with secondary effects on issues such as determining its prevalence. After review of the literature and the problems inherent to diagnoses based solely on behavioural data, we propose as a starting discussion point a set of two primary and four secondary criteria for the diagnosis of developmental prosopagnosia.
Topics: Face; Humans; Pattern Recognition, Visual; Prosopagnosia; Recognition, Psychology
PubMed: 27312748
DOI: 10.1016/j.neuropsychologia.2016.06.008 -
Wiley Interdisciplinary Reviews.... 2016Developmental prosopagnosia (DP) is a neurodevelopmental condition characterized by severe face identity recognition problems that results from a failure to develop the... (Review)
Review
Developmental prosopagnosia (DP) is a neurodevelopmental condition characterized by severe face identity recognition problems that results from a failure to develop the mechanisms necessary for adequate face processing (Duchaine BC, Nakayama K. Developmental prosopagnosia: a window to content-specific face processing. Curr Opin Neurobiol 2006, 16:166-173.). It occurs in children and adults with normal visual acuity, and without intellectual impairments or known brain injuries. Given the importance of face recognition in daily life, and the detrimental effects of impaired face recognition, DP is an important area of study. Yet conventions for classifying individuals as DP for research purposes are poorly defined. In this focus paper, we discuss: (1) criteria for an operational definition of DP; 2) tests of face recognition and conventions for classifying individuals as DP; and 3) important considerations regarding common associations and dissociations, and cognitive heterogeneity in DP. We also highlight issues unique to studying DP in children, a relatively new endeavor that is proving to be an important complement to the work with adults. Ultimately, we hope to identify challenges researchers face when studying DP, and offer guidelines for others to consider when embarking on their own research pursuits on the topic. For further resources related to this article, please visit the WIREs website.
Topics: Adult; Age Factors; Child; Female; Humans; Male; Neuropsychological Tests; Prosopagnosia; Research Design
PubMed: 26681428
DOI: 10.1002/wcs.1374 -
Frontiers in Rehabilitation Sciences 2023Benign paroxysmal positional vertigo (BPPV) is a common condition with disabling symptoms that is diagnosed and effectively treated at the bedside. Our encounter with...
INTRODUCTION
Benign paroxysmal positional vertigo (BPPV) is a common condition with disabling symptoms that is diagnosed and effectively treated at the bedside. Our encounter with patients experiencing prolonged BPPV who may not have received appropriate physical therapy prompted us to explore barriers to the diagnosis and treatment for BPPV among physical therapists, which has not been extensively investigated. We hypothesize that a potential barrier may be a lack of understanding of subtle symptoms of BPPV that deviate from the classical presentation. The gold standard for diagnosing definite BPPV is subjective dizziness or vertigo with nystagmus in response to positional testing. There are variants of BPPV including subjective BPPV (subjective dizziness or vertigo without nystagmus) and vestibular agnosia (nystagmus without subjective dizziness or vertigo) that do not meet the diagnostic criteria for definite BPPV but are equally responsive to the same repositioning maneuvers. The purpose of this project was to survey physical therapists for their understanding of BPPV including subjective BPPV and vestibular agnosia.
METHODS
A panel of experts created a 16-question survey, designed for physical therapists, with three categories: (1), inquiring if they treat persons with BPPV, (2) three clinical vignettes for definite BPPV, subjective BPPV, and BPPV with vestibular agnosia, and (3) demographic information. Data collection occurred at two large physical therapy meetings, one of which was a national professional meeting and the other was a professional continuing medical education course geared towards advancing vestibular rehabilitation skills.
RESULTS
There were 426 people who completed the survey, 364 of whom treat BPPV in their practice. In the first clinical vignette created to assess the respondents' understanding of definite BPPV, 229 (62%) of respondents would always assess a patient for BPPV based on complaints of a "room spinning" vertigo from head movement. When asked if the complaint was lingering "lightheadedness or feelings of imbalance" from head movement, only 158 (43%) reported they would perform positional testing to reassess. In the BPPV variant vignettes, 187 (51%) identified the patient with subjective BPPV as having BPPV and 305 (85%) identified the patient with vestibular agnosia as having BPPV.
DISCUSSION
The results of this survey demonstrate gaps in knowledge regarding BPPV across practice settings and experience, with opportunities to bridge these gaps to improve treatment for BPPV.
PubMed: 37662546
DOI: 10.3389/fresc.2023.1228453 -
Neurology India 2021Reflected image processing is a unique brain function and its abnormalities result in problems of localizing, recognizing the images, and utilizing this information in...
BACKGROUND
Reflected image processing is a unique brain function and its abnormalities result in problems of localizing, recognizing the images, and utilizing this information in everyday life.
OBJECTIVES
The aim of this study was to characterize clinical and neuropsychological profiles and to identify the probable neural substrate for this phenomenon in major cognitive disorder.
MATERIALS AND METHODS
We conducted a prospective study from February 2015 to May 2017 in patients with Major Cognitive Disorder (MCD, DSM-5 criteria). All patients were tested for problems in reflected image processing using the detailed protocol after ethical approval of the institute and consent. They also underwent a detailed neuropsychological evaluation, biochemical tests and neuroimaging (structural, diffusion, and resting-state functional MRI) as per established protocol.
RESULTS
Of the 18 patients, 11 had mirror agnosia (MA), 5 had mirror image agnosia (MIA) and 2 had both. MRI of MA patients showed parietal atrophy and whereas diffuse pattern of atrophy was seen with MIA. In the MA group, the left superior longitudinal fasciculus showed significantly greater fractional anisotropy and the left angular gyrus showed increased functional connectivity with left anterior cingulate, left dorsolateral prefrontal and bilateral posterior cingulate regions.
CONCLUSION
Mirror image processing defects were not related to the type of MCD, severity or pattern of neuropsychological dysfunction. There are structural and functional alterations in localized regions as well as both hemispheres. Therefore, it is more likely to be a network disorder, irrespective of the MCD type or severity.
Topics: Agnosia; Humans; Magnetic Resonance Imaging; Neuropsychological Tests; Prospective Studies; White Matter
PubMed: 34507415
DOI: 10.4103/0028-3886.325339 -
The Lancet. Neurology Dec 2016Autosomal dominant familial Alzheimer's disease (ADAD) is a rare disorder with non-amnestic neurological symptoms in some clinical presentations. We aimed to compile and... (Comparative Study)
Comparative Study Meta-Analysis Review
Neurological manifestations of autosomal dominant familial Alzheimer's disease: a comparison of the published literature with the Dominantly Inherited Alzheimer Network observational study (DIAN-OBS).
BACKGROUND
Autosomal dominant familial Alzheimer's disease (ADAD) is a rare disorder with non-amnestic neurological symptoms in some clinical presentations. We aimed to compile and compare data from symptomatic participants in the Dominantly Inherited Alzheimer Network observational study (DIAN-OBS) with those reported in the literature to estimate the prevalences of non-amnestic neurological symptoms in participants with ADAD.
METHODS
We prospectively collected data from the DIAN-OBS database, which recruited participants from study centres in the USA, Europe, and Australia, between Feb 29, 2008, and July 1, 2014. We also did a systematic review of publications to extract individual-level clinical data for symptomatic participants with ADAD. We used data for age of onset (from first report of cognitive decline), disease course from onset to death, and the presence of 13 neurological findings that have been reported in association with ADAD. Using multivariable linear regression, we investigated the prevalences of various non-amnestic neurological symptoms and the contributions of age of onset and specific mutation type on symptoms.
FINDINGS
The DIAN-OBS dataset included 107 individuals with detailed clinical data (forming the DIAN-OBS cohort). Our systematic review yielded 188 publications reporting on 1228 symptomatic individuals, with detailed neurological examination descriptions available for 753 individuals (forming the published data cohort). The most prevalent non-amnestic cognitive manifestations in participants in the DIAN-OBS cohort were those typical of mild to moderate Alzheimer's disease, including visual agnosia (55·1%, 95% CI 45·7-64·6), aphasia (57·9%, 48·6-67·3), and behavioural changes (61·7%, 51·5-70·0). Non-amnestic cognitive manifestations were less prevalent in the published data cohort (eg, visual agnosia [5·6%, 3·9-7·2], aphasia [23·0%, 20·0-26·0], and behavioural changes [31·7%, 28·4-35·1]). Prevalence of non-cognitive neurological manifestations in the DIAN-OBS cohort was low, including myoclonus and spasticity (9·3%, 95% CI 3·8-15·0), and seizures (2·8%, 0·5-5·9) and moderate for parkinsonism (11·2%, 5·3-17·1). By constrast, prevalence was higher in the published data cohort for myoclonus and spasticity (19·4%, 16·6-22·2 and 15·0%, 12·5-17·6, respectively), parkinsonism (12·5%, 10·1-15·0), and seizures (20·3%, 17·4-23·2). In an analysis of the published data cohort, ischaemic stroke was more prevalent at older ages of onset of symptoms of ADAD (odds ratio 1·09 per 1 year increase in age of onset, 95% CI 1·04-1·14, p=0·0003); and motor symptoms were more common at younger age of onset (myoclonus 0·93, 0·90-0·97, p=0·0007; seizures 0·95, 0·92-0·98, p=0·0018; corticobulbar deficits 0·91, 0·86-0·96, p=0·0012; and cerebellar ataxia 0·82, 0·74-0·91, p=0·0002). In the DIAN-OBS cohort, non-cognitive symptoms were more common at more severe stages of disease.
INTERPRETATION
The non-cognitive clinical manifestations of Alzheimer's disease seem to affect a small proportion of participants with mild to moderate ADAD, and are probably influenced by disease severity, environmental, and genetic factors. When evaluating patients with potential ADAD, clinicians should note that cognitive symptoms typical of sporadic Alzheimer's disease are the most consistent finding, with some patients manifesting non-cognitive neurological symptoms. Future work is needed to determine the environmental and genetic factors that cause these neurological symptoms.
FUNDING
National Institutes of Health and German Center for Neurodegenerative Diseases.
Topics: Alzheimer Disease; Humans
PubMed: 27777020
DOI: 10.1016/S1474-4422(16)30229-0 -
The British Journal of General Practice... 2021
Topics: Agnosia; Humans
PubMed: 33509822
DOI: 10.3399/bjgp21X714797 -
Scientific Reports Nov 2017Visual crowding is a perceptual phenomenon with far-reaching implications in both perceptual (e.g., object recognition and reading) and clinical (e.g., developmental...
Visual crowding is a perceptual phenomenon with far-reaching implications in both perceptual (e.g., object recognition and reading) and clinical (e.g., developmental dyslexia and visual agnosia) domains. Here, we combined event-related fMRI measurements and wide-field brain mapping methods to investigate whether the BOLD response evoked by visual crowding is modulated by different attentional conditions. Participants underwent two sessions of psychophysical training outside the scanner, and then fMRI BOLD activity was measured simultaneously in early visual areas (including the visual word form area, VWFA), while they viewed strongly-crowded and weakly-crowded Gabor patches in attended and unattended conditions. We found that crowding increased BOLD activity in a network of areas including V1, V2, V3A, V4/V8, and VWFA. In V4/V8 and VWFA we found an increased activity related to attention. The effect of crowding in V1 was recorded only when attention was fully devoted to the target location. Our results provide evidence that some area beyond V1 might be the likely candidate for the site of crowding, thus supporting the view of visual crowding as a mid-level visual phenomenon.
Topics: Attention; Brain Mapping; Crowding; Evoked Potentials, Visual; Humans; Magnetic Resonance Imaging; Visual Cortex; Visual Perception
PubMed: 29093537
DOI: 10.1038/s41598-017-13921-z -
Acta Neurologica Taiwanica Dec 2022A 56-year-old, right-handed man with no known past medical history presented with sudden onset of inability to recognize familiar individuals in person, including his...
A 56-year-old, right-handed man with no known past medical history presented with sudden onset of inability to recognize familiar individuals in person, including his wife and his mother. He also couldn't recognize himself in the mirror. There was no weakness, numbness, visual disturbances, or speech difficulty. Face recognition test, using Warrington Recognition Memory Test (1), showed the presence of complete prosopagnosia. The rest of the neurological and cranial nerves examinations were normal. Magnetic resonance imaging (MRI) of the brain showed restricted diffusion at the right temporal and occipital lobes (the fusiform gyrus) [Figure 1]. Magnetic resonance angiogram (MRA) of the brain was unremarkable. The 24-hours Holter monitoring showed paroxysmal atrial fibrillation. The transthoracic echocardiogram and carotid doppler ultrasound scan were normal. He was then treated with rivaroxaban 20mg daily for secondary stroke prevention in non-valvular atrial fibrillation. Face recognition skill training was started in the ward, which includes compensatory strategies to achieve person recognition by circumventing the face processing impairment, and remediation to enhance mnemonic function for face recognition. His prosopagnosia resolved completely after one week. Prosopagnosia, also known as face blindness, is an impairment in recognizing faces. The core defects are the loss of familiarity with previously known faces and the inability to recognize new faces. Patients with prosopagnosia may present with poor recognition of familiar individuals in person or in the photograph, confusion with plotlines in movies or plays with numerous characters, and difficulty distinguishing individuals wearing a uniform or similar clothing. Stroke is the most common cause of acquired prosopagnosia (2). Other less common aetiologies include traumatic brain injury, carbon monoxide poisoning, temporal lobectomy, and encephalitis. Literature has shown that areas involved in acquired prosopagnosia are the right fusiform gyrus or anterior temporal cortex, or both (3). The fusiform gyrus is part of the lateral temporal lobe and occipital lobe in 'Brodmann area 37' (4). The fusiform gyrus is considered a key structure for functionally specialized computations of high-level vision such as face perception, object recognition, and reading. Individuals with fusiform lesions are more likely to have apperceptive prosopagnosia, while those with anterior temporal lesions have an amnestic variant (5). In summary, prosopagnosia can be the sole presentation for the right fusiform gyrus stroke. It is important to recognize prosopagnosia for early stroke diagnosis and avoid misdiagnosing it as a psychiatric or ocular disorder. Keywords: prosopagnosia, fusiform gyrus, stroke.
Topics: Humans; Infarction; Magnetic Resonance Imaging; Male; Middle Aged; Occipital Lobe; Prosopagnosia; Stroke; Temporal Lobe
PubMed: 35470413
DOI: No ID Found -
Current Neurology and Neuroscience... Mar 2017The current review integrates recent findings regarding the construct of self-awareness in dementia from both clinical and cognitive perspectives. We present the... (Review)
Review
The current review integrates recent findings regarding the construct of self-awareness in dementia from both clinical and cognitive perspectives. We present the predominant theoretical models of awareness and summarize both traditional and emerging approaches to assessing awareness from clinical and meta-cognitive perspectives. In this review, we focus primarily on findings from recent studies in anosognosia and meta-cognition in the context of neurodegenerative disease with special emphasis on Alzheimer's disease and frontotemporal dementia. Emerging trends in the study of awareness, including examination of the longitudinal course of anosognosia, and investigation of the neural substrates underlying meta-cognitive abilities are addressed. Finally, the practical importance of studying and assessing awareness from both theoretical and clinical angles is emphasized.
Topics: Aged; Agnosia; Alzheimer Disease; Awareness; Frontotemporal Dementia; Humans; Metacognition; Models, Psychological; Neuropsychological Tests
PubMed: 28283961
DOI: 10.1007/s11910-017-0734-1 -
Neuropsychologia Jun 2022In right-handed adults, face processing is lateralized to the right hemisphere and visual word processing to the left hemisphere. According to the many-to-many account...
In right-handed adults, face processing is lateralized to the right hemisphere and visual word processing to the left hemisphere. According to the many-to-many account (MTMA) of functional cerebral organization this lateralization pattern is partly dependent on the acquisition of literacy. Hence, the MTMA predicts that: (i) processing of both words and faces should show no or at least less lateralization in individuals with developmental dyslexia compared with controls, and (ii) lateralization in word processing should be normal in individuals with developmental prosopagnosia whereas lateralization in face processing should be absent. To test these hypotheses, 21 right-handed adults with developmental dyslexia and 21 right-handed adults with developmental prosopagnosia performed a divided visual field paradigm with delayed matching of faces, words and cars. Contrary to the predictions, we find that lateralization effects in face processing are within the normal range for both developmental dyslexics and prosopagnosics. Moreover, the group with developmental dyslexia showed right hemisphere lateralization for word processing. We argue that these findings are incompatible with the specific predictions of the MTMA.
Topics: Adult; Dyslexia; Facial Recognition; Functional Laterality; Humans; Pattern Recognition, Visual; Prosopagnosia; Visual Perception
PubMed: 35278463
DOI: 10.1016/j.neuropsychologia.2022.108208