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Scientific Reports Mar 2024Developmental prosopagnosia (DP) is characterised by deficits in face identification. However, there is debate about whether these deficits are primarily perceptual, and...
Developmental prosopagnosia (DP) is characterised by deficits in face identification. However, there is debate about whether these deficits are primarily perceptual, and whether they extend to other face processing tasks (e.g., identifying emotion, age, and gender; detecting faces in scenes). In this study, 30 participants with DP and 75 controls completed a battery of eight tasks assessing four domains of face perception (identity; emotion; age and gender; face detection). The DP group performed worse than the control group on both identity perception tasks, and one task from each other domain. Both identity perception tests uniquely predicted DP/control group membership, and performance on two measures of face memory. These findings suggest that deficits in DP may arise from issues with face perception. Some non-identity tasks also predicted DP/control group membership and face memory, even when face identity perception was accounted for. Gender perception and speed of face detection consistently predicted unique variance in group membership and face memory; several other tasks were only associated with some measures of face recognition ability. These findings indicate that face perception deficits in DP may extend beyond identity perception. However, the associations between tasks may also reflect subtle aspects of task demands or stimuli.
Topics: Humans; Facial Recognition; Prosopagnosia; Emotions; Pattern Recognition, Visual
PubMed: 38503841
DOI: 10.1038/s41598-024-57176-x -
Scientific Reports Mar 2024Congenital Prosopagnosia (CP) is an innate impairment in face perception with heterogeneous characteristics. It is still unclear if and to what degree holistic...
Congenital Prosopagnosia (CP) is an innate impairment in face perception with heterogeneous characteristics. It is still unclear if and to what degree holistic processing of faces is disrupted in CP. Such disruption would be expected to lead to a focus on local features of the face. In this study, we used binocular rivalry (BR) to implicitly measure face perception in conditions that favour holistic or local processing. The underlying assumption is that if stimulus saliency affects the perceptual dominance of a given stimulus in BR, one can deduce how salient a stimulus is for a given group (here: participants with and without CP) based on the measured perceptual dominance. A further open question is whether the deficit in face processing in CP extends to the processing of the facial display of emotions. In experiment 1, we compared predominance of upright and inverted faces displaying different emotions (fearful, happy, neutral) vs. houses between participants with CP (N = 21) and with normal face perception (N = 21). The results suggest that CP observers process emotions in faces automatically but rely more on local features than controls. The inversion of faces, which is supposed to disturb holistic processing, affected controls in a more pronounced way than participants with CP. In experiment 2, we introduced the Thatcher effect in BR by inverting the eye and mouth regions of the presented faces in the hope of further increasing the effect of face inversion. However, our expectations were not borne out by the results. Critically, both experiments showed that inversion effects were more pronounced in controls than in CP, suggesting that holistic face processing is less relevant in CP. We find BR to be a useful implicit test for assessing visual processing specificities in neurological participants.
Topics: Humans; Facial Recognition; Prosopagnosia; Pattern Recognition, Visual; Visual Perception; Photic Stimulation
PubMed: 38509151
DOI: 10.1038/s41598-024-55023-7 -
Rinsho Shinkeigaku = Clinical Neurology Mar 2024A 58-year-old, right-handed man noticed difficulty in typing and speech. On day 3 after onset, the day of admission, he had frontal lobe dysfunction including verbal...
A 58-year-old, right-handed man noticed difficulty in typing and speech. On day 3 after onset, the day of admission, he had frontal lobe dysfunction including verbal fluency impairment and impairment of recent memory, although he did not have apraxia or visual agnosia. Moreover, he had difficulty typing in romaji, especially words containing contracted or double consonant sounds, although he was able to do this before onset by visually checking the keyboard. He had mild dysgraphia. MRI showed an infarct in the genu and posterior limb of the left internal capsule. SPECT revealed low-uptake lesions in the left frontal lobe. In the present case, we consider that the subcortical infarction disrupted the network between the thalamus and frontal lobe, resulting in dystypia due to difficulty with recalling romaji spelling.
Topics: Male; Humans; Middle Aged; Ischemic Stroke; Cerebral Infarction; Agnosia; Magnetic Resonance Imaging; Language
PubMed: 38369328
DOI: 10.5692/clinicalneurol.cn-001904 -
The American Journal of Occupational... Mar 2024Unilateral spatial neglect (neglect) poststroke is disabling. It is critical that people with neglect are identified so that treatment can be provided to maximize...
IMPORTANCE
Unilateral spatial neglect (neglect) poststroke is disabling. It is critical that people with neglect are identified so that treatment can be provided to maximize independence. However, there is some evidence to suggest that existing assessments may not adequately measure neglect. It is unclear whether assessments also fail to identify people with neglect entirely.
OBJECTIVE
To determine whether there are stroke survivors who self-report neglect symptoms that are not detected by therapist-rated assessments and to compare self-report and therapist-ratings.
DESIGN
Cross-sectional study.
SETTING
U.S. university research center.
PARTICIPANTS
Unilateral stroke survivors (N = 133).
INTERVENTION
Not applicable.
OUTCOMES AND MEASURES
The Catherine Bergego Scale (CBS) was administered to participants and scored by a trained occupational therapist. The parallel self-evaluation anosognosia form was also administered to participants to self-report and rate neglect symptoms.
RESULTS
Forty-eight participants (36.1%) were classified as without neglect on the basis of therapist-rated total CBS scores, yet 30 (62.5%) of these 48 participants reported symptoms of neglect on the CBS self-evaluation anosognosia form. There was a significant difference (p < .001) between therapist-rated and self-rated total CBS scores.
CONCLUSIONS AND RELEVANCE
Our results indicate that many stroke survivors report some level of disability associated with neglect yet do not meet the criteria to be classified as having neglect according to a commonly used therapist-rated performance-based measure. Plain-Language Summary: The findings of this study contribute to the evidence that existing assessments used by occupational therapists to measure performance-based neglect may not always detect neglect symptoms comprehensively in people poststroke. The finding also suggest that we may be missing neglect symptoms entirely. Occupational therapists should consider using various methods to assess for neglect, including patient self-report and comprehensive occupational profiles. Clinicians should also thoroughly screen all clients with stroke for neglect, regardless of lesion location.
Topics: Humans; Cross-Sectional Studies; Perceptual Disorders; Agnosia; Stroke; Stroke Rehabilitation
PubMed: 38350038
DOI: 10.5014/ajot.2024.050497 -
Physiotherapy Theory and Practice Oct 2023This report examines the effects of a multimodal rehabilitation program which includes cognitive, physical, and somatosensory rehabilitation after right temporo-parietal...
The effects of cognitive, physical, and somatosensory rehabilitation after right temporo-parietal tumor resection on cognitive, motor, somatosensory, and electrophysiological parameters: A case report.
INTRODUCTION
This report examines the effects of a multimodal rehabilitation program which includes cognitive, physical, and somatosensory rehabilitation after right temporo-parietal tumor resection on cognitive, motor, somatosensory, and electrophysiological parameters.
CASE DESCRIPTION
A 22-year-old patient presented with sensory loss in the dominant left hand and reduced writing ability after right temporo-parietal lobe resection. Cognitive, motor, and sensory evaluations were carried out pre and post-treatment. The patient's spontaneous electroencephalo-gram (EEG) and an EEG during application of transcutaneous electrical nerve stimulation (TENS) (TENS EEG) were recorded. As a reference for the patient's electrophysiological values, EEGs of 4 healthy individuals were also taken. Over a period of 1 year, the patient received multimodal rehabilitation which includes cognitive, physical, and somato-sensory rehabilitation on 2 days each week.
OUTCOMES
An improvement of the patient's cognitive capacities, motor strength, superficial, deep and cortical sensations was achieved. After rehabilitation, an increase in parietal and occipital alpha activity as well as in frontal and parietal beta activity was seen both in spontaneous EEG and in TENS EEG. With increasing TENS intensity, alpha and beta power increased as well.
CONCLUSION
Our findings suggest that a multimodal rehabilitation program may improve cognitive, sensory, and motor effects after resection due to tumor surgery.
Topics: Humans; Young Adult; Adult; Parietal Lobe; Hand; Electroencephalography; Cognition; Neoplasms; Transcutaneous Electric Nerve Stimulation
PubMed: 35436161
DOI: 10.1080/09593985.2022.2064787 -
Internal Medicine (Tokyo, Japan) Feb 2024A 73-year-old woman with posterior cortical atrophy (PCA) presented with progressive apperceptive visual agnosia, alexia, agraphia, ventral simultanagnosia,...
A 73-year-old woman with posterior cortical atrophy (PCA) presented with progressive apperceptive visual agnosia, alexia, agraphia, ventral simultanagnosia, prosopagnosia, and allocentric (stimulus-centered) left-sided hemispatial neglect. All of these symptoms were attributed to damage to the bilateral occipito-temporal cortices, consistent with ventral variant PCA. While the Pittsburgh compound B uptake was extensively distributed throughout the occipito-parietal (dorsal) and occipito-temporal (ventral) areas, the THK5351 (ligand binding to tau aggregates/astrocyte gliosis) accumulation was limited to the ventral area. These findings suggest that local accumulation of tau proteins and/or astrocyte gliosis over the occipito-temporal cortices can result in ventral variant PCA.
PubMed: 38369357
DOI: 10.2169/internalmedicine.2844-23 -
Perception Sep 2023Aphantasia and prosopagnosia are both rare conditions with impairments in visual cognition. While prosopagnosia refers to a face recognition deficit, aphantasics exhibit...
Aphantasia and prosopagnosia are both rare conditions with impairments in visual cognition. While prosopagnosia refers to a face recognition deficit, aphantasics exhibit a lack of mental imagery. Current object recognition theories propose an interplay of perception and mental representations, making an association between recognition performance and visual imagery plausible. While the literature assumes a link between aphantasia and prosopagnosia, other impairments in aphantasia have been shown to be rather global. Therefore, we assumed that aphantasics do not solely exhibit impairments in face recognition but rather in general visual recognition performance, probably moderated by stimulus complexity. To test this hypothesis, 65 aphantasics were compared to 55 controls in a face recognition task, the Cambridge Face Memory Test, and a corresponding object recognition task, the Cambridge Car Memory Test. In both tasks, aphantasics performed worse than controls, indicating mild recognition deficits without face-specificity. Additional correlations between imagery vividness and performance in both tasks were found, suggesting that visual imagery influences visual recognition not only in imagery extremes. Stimulus complexity produced the expected moderation effect but only for the whole imagery-spectrum and only with face stimuli. Overall, the results imply that aphantasia is linked to a general but mild deficit in visual recognition.
Topics: Humans; Prosopagnosia; Prevalence; Recognition, Psychology; Cognition; Visual Perception; Pattern Recognition, Visual
PubMed: 37321679
DOI: 10.1177/03010066231180712 -
Neuro-ophthalmology (Aeolus Press) 2024Vision specialists will benefit from increased awareness of posterior cortical atrophy (PCA) syndrome. Failure to adequately identify the chief complaint as a visual...
Vision specialists will benefit from increased awareness of posterior cortical atrophy (PCA) syndrome. Failure to adequately identify the chief complaint as a visual symptom may lead to incorrect diagnosis or diagnostic delay. A previously healthy, 59-year-old woman presented with a 5-year history of 'losing her stuff'. Upon psychiatric and neuro-ophthalmological evaluation, this symptom was better recognised as a feature of visual agnosia and simultanagnosia. She also presented with multiple previously unrecognised symptoms indicative of higher visual processing dysfunction, such as alexia without agraphia, ocular motor apraxia, optic ataxia, prosopagnosia, akinetopsia and topographagnosia, so further assessment to investigate for PCA was carried out. After a work-up including cognitive assessment, brain structural/functional imaging, and laboratory tests she was diagnosed with visual-variant Alzheimer's disease. Patients with PCA merit a detailed review of their symptoms, as well as the use of office tests such as cognitive evaluation tools, different types of perimetry, colour vision tests, and non-delayed psychiatric consultation for correct management and assessment. This report will emphasise five key aspects to be considered when evaluating patients with PCA.
PubMed: 38357623
DOI: 10.1080/01658107.2023.2257311 -
Neuropsychologia Nov 2023Neuroimaging and intracranial electrophysiological studies have consistently shown the largest and most consistent face-selective neural activity in the middle portion...
Neuroimaging and intracranial electrophysiological studies have consistently shown the largest and most consistent face-selective neural activity in the middle portion of the human right lateral fusiform gyrus ('fusiform face area(s)', FFA). Yet, direct evidence for the critical role of this region in face identity recognition (FIR) is still lacking. Here we report the first evidence of transient behavioral impairment of FIR during focal electrical stimulation of the right FFA. Upon stimulation of an electrode contact within this region, subject CJ, who shows typical FIR ability outside of stimulation, was transiently unable to point to pictures of famous faces among strangers and to match pictures of famous or unfamiliar faces presented simultaneously for their identity. Her performance at comparable tasks with other visual materials (written names, pictures of buildings) remained unaffected by stimulation at the same location. During right FFA stimulation, CJ consistently reported that simultaneously presented faces appeared as being the same identity, with little or no distortion of the spatial face configuration. Independent electrophysiological recordings showed the largest neural face-selective and face identity activity at the critical electrode contacts. Altogether, this extensive multimodal case report supports the causal role of the right FFA in FIR.
Topics: Female; Humans; Pattern Recognition, Visual; Prosopagnosia; Magnetic Resonance Imaging; Facial Recognition; Temporal Lobe; Electric Stimulation; Photic Stimulation; Brain Mapping
PubMed: 37839512
DOI: 10.1016/j.neuropsychologia.2023.108705 -
Cortex; a Journal Devoted To the Study... Sep 2023Unawareness of memory deficits is an early manifestation in patients with Alzheimer's disease (AD), which often delays diagnosis. This intriguing behavior constitutes a...
Unawareness of memory deficits is an early manifestation in patients with Alzheimer's disease (AD), which often delays diagnosis. This intriguing behavior constitutes a form of anosognosia, whose neural mechanisms remain largely unknown. We hypothesized that anosognosia may depend on a critical synaptic failure in the error-monitoring system, which would prevent AD patients from being aware of their own memory impairment. To investigate, we measured event-related potentials (ERPs) evoked by erroneous responses during a word memory recognition task in two groups of amyloid positive individuals with only subjective memory complaints at study entry: those who progressed to AD within the five-year study period (PROG group), and those who remained cognitively normal (CTRL group). A significant reduction in the amplitude of the positivity error (Pe), an ERP related to error awareness, was observed in the PROG group at the time of AD diagnosis (vs study entry) in intra-group analysis, as well as when compared with the CTRL group in inter-group analysis, based on the last EEG acquisition for all subjects. Importantly, at the time of AD diagnosis, the PROG group exhibited clinical signs of anosognosia, overestimating their cognitive abilities, as evidenced by the discrepancy scores obtained from caregiver/informant vs participant reports on the cognitive subscale of the Healthy Aging Brain Care Monitor. To our knowledge, this is the first study to reveal the emergence of a failure in the error-monitoring system during a word memory recognition task at the early stages of AD. This finding, along with the decline of awareness for cognitive impairment observed in the PROG group, strongly suggests that a synaptic dysfunction in the error-monitoring system may be the critical neural mechanism at the origin of unawareness of deficits in AD.
Topics: Humans; Male; Female; Aged; Aged, 80 and over; Alzheimer Disease; Memory Disorders; Electroencephalography; Evoked Potentials; Agnosia; Synapses; Neuropsychological Tests; Recognition, Psychology
PubMed: 37423786
DOI: 10.1016/j.cortex.2023.05.014