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Behavior Research Methods Dec 2023Developmental prosopagnosia is characterized by severe, lifelong difficulties when recognizing facial identity. Unfortunately, the most common diagnostic assessment...
Developmental prosopagnosia is characterized by severe, lifelong difficulties when recognizing facial identity. Unfortunately, the most common diagnostic assessment (Cambridge Face Memory Test) misses 50-65% of individuals who believe that they have this condition. This results in such excluded cases' absence from scientific knowledge, effect sizes of impairment potentially overestimated, treatment efficacy underrated, and may elicit in them a negative experience of research. To estimate their symptomology and group-level impairments in face processing, we recruited a large cohort who believes that they have prosopagnosia. Matching prior reports, 56% did not meet criteria on the Cambridge Face Memory Test. However, the severity of their prosopagnosia symptoms and holistic perception deficits were comparable to those who did meet criteria. Excluded cases also exhibited face perception and memory impairments that were roughly one standard deviation below neurotypical norms, indicating the presence of objective problems. As the prosopagnosia index correctly classified virtually every case, we propose it should be the primary method for providing a diagnosis, prior to subtype categorization. We present researchers with a plan on how they can analyze these excluded prosopagnosia cases in their future work without negatively impacting their traditional findings. We anticipate such inclusion will enhance scientific knowledge, more accurately estimate effect sizes of impairments and treatments, and identify commonalities and distinctions between these different forms of prosopagnosia. Owing to their atypicalities in visual perception, we recommend that the prosopagnosia index should be used to screen out potential prosopagnosia cases from broader vision research.
Topics: Humans; Prosopagnosia; Recognition, Psychology; Visual Perception; Facial Recognition; Pattern Recognition, Visual
PubMed: 36459376
DOI: 10.3758/s13428-022-02017-w -
Frontiers in Psychology 2017Face and word recognition have traditionally been thought to rely on highly specialised and relatively independent cognitive processes. Some of the strongest evidence... (Review)
Review
Face and word recognition have traditionally been thought to rely on highly specialised and relatively independent cognitive processes. Some of the strongest evidence for this has come from patients with seemingly category-specific visual perceptual deficits such as pure prosopagnosia, a selective face recognition deficit, and pure alexia, a selective word recognition deficit. Together, the patterns of impaired reading with preserved face recognition and impaired face recognition with preserved reading constitute a double dissociation. The existence of these selective deficits has been questioned over the past decade. It has been suggested that studies describing patients with these pure deficits have failed to measure the supposedly preserved functions using sensitive enough measures, and that if tested using sensitive measurements, all patients with deficits in one visual category would also have deficits in the other. The implications of this would be immense, with most textbooks in cognitive neuropsychology requiring drastic revisions. In order to evaluate the evidence for dissociations, we review studies that specifically investigate whether face or word recognition can be selectively affected by acquired brain injury or developmental disorders. We only include studies published since 2004, as comprehensive reviews of earlier studies are available. Most of the studies assess the supposedly preserved functions using sensitive measurements. We found convincing evidence that reading can be preserved in acquired and developmental prosopagnosia and also evidence (though weaker) that face recognition can be preserved in acquired or developmental dyslexia, suggesting that face and word recognition are at least in part supported by independent processes.
PubMed: 28932205
DOI: 10.3389/fpsyg.2017.01547 -
Journal of Neurology, Neurosurgery, and... Nov 1962
Topics: Agnosia; Humans; Intracranial Arteriosclerosis; Occipital Lobe; Parietal Lobe; Prosopagnosia
PubMed: 13943018
DOI: 10.1136/jnnp.25.4.336 -
Frontiers in Neuroanatomy 2018The inferior longitudinal fasciculus (ILF) is a long-range, associative white matter pathway that connects the occipital and temporal-occipital areas of the brain to the... (Review)
Review
The inferior longitudinal fasciculus (ILF) is a long-range, associative white matter pathway that connects the occipital and temporal-occipital areas of the brain to the anterior temporal areas. In view of the ILF's anatomic connections, it has been suggested that this pathway has a major role in a relatively large array of brain functions. Until recently, however, the literature data on these potential functions were scarce. Here, we review the key findings of recent anatomic, neuromodulation, and neuropsychological studies. We also summarize reports on how this tract is disrupted in a wide range of brain disorders, including psychopathologic, neurodevelopmental, and neurologic diseases. Our review reveals that the ILF is a multilayered, bidirectional tract involved in processing and modulating visual cues and thus in visually guided decisions and behaviors. Accordingly, sudden disruption of the ILF by neurologic insult is mainly associated with neuropsychological impairments of visual cognition (e.g., visual agnosia, prosopagnosia, and alexia). Furthermore, disruption of the ILF may constitute the pathophysiologic basis for visual hallucinations and socio-emotional impairments in schizophrenia, as well as emotional difficulties in autism spectrum disorder. Degeneration of the ILF in neurodegenerative diseases affecting the temporal lobe may explain (at least in part) the gradual onset of semantic and lexical access difficulties. Although some of the functions mediated by the ILF appear to be relatively lateralized, observations from neurosurgery suggest that disruption of the tract's anterior portion can be dynamically compensated for by the contralateral portion. This might explain why bilateral disruption of the ILF in either acute or progressive disease is highly detrimental in neuropsychological terms.
PubMed: 30283306
DOI: 10.3389/fnana.2018.00077 -
Cortex; a Journal Devoted To the Study... Mar 2016Previous studies report that acquired prosopagnosia is frequently associated with topographic disorientation. Whether this is associated with a specific anatomic subtype...
Previous studies report that acquired prosopagnosia is frequently associated with topographic disorientation. Whether this is associated with a specific anatomic subtype of prosopagnosia, how frequently it is seen with the developmental variant, and what specific topographic function is impaired to account for this problem are not known. We studied ten subjects with acquired prosopagnosia from either occipitotemporal or anterior temporal (AT) lesions and seven with developmental prosopagnosia. Subjects were given a battery of topographic tests, including house and scene recognition, the road map test, a test of cognitive map formation, and a standardized self-report questionnaire. House and/or scene recognition were frequently impaired after either occipitotemporal or AT lesions in acquired prosopagnosia. Subjects with occipitotemporal lesions were also impaired in cognitive map formation: an overlap analysis identified right fusiform and parahippocampal gyri as a likely correlate. Only one subject with acquired prosopagnosia had mild difficulty with directional orientation on the road map test. Only one subject with developmental prosopagnosia had difficulty with cognitive map formation, and none were impaired on the other tests. Scores for house and scene recognition correlated most strongly with the results of the questionnaire. We conclude that topographic disorientation in acquired prosopagnosia reflects impaired place recognition, with a contribution from poor cognitive map formation when there is occipitotemporal damage. Topographic impairments are less frequent in developmental prosopagnosia.
Topics: Adult; Aged; Discrimination, Psychological; Face; Female; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Occipital Lobe; Orientation; Prosopagnosia; Temporal Lobe; Young Adult
PubMed: 26874939
DOI: 10.1016/j.cortex.2016.01.003 -
Seminars in Speech and Language Feb 2018Despite its basic and translational importance, the neural circuitry supporting the perception of emotional faces remains incompletely understood. Functional imaging... (Review)
Review
Despite its basic and translational importance, the neural circuitry supporting the perception of emotional faces remains incompletely understood. Functional imaging studies and chronic lesion studies indicate distinct roles of the amygdala and insula in recognition of fear and disgust in facial expressions, whereas intracranial encephalography studies, which are not encumbered by variations in human anatomy, indicate a somewhat different role of these structures. In this article, we leveraged lesion-mapping techniques in individuals with right hemisphere stroke to investigate lesions associated with impaired recognition of prototypic emotional faces before significant neural reorganization can occur during recovery from stroke. Right hemisphere stroke patients were significantly less accurate than controls on a test of emotional facial recognition for both positive and negative emotions. Patients with right amygdala or anterior insula lesions had significantly lower scores than other right hemisphere stroke patients on recognition of angry and happy faces. Lesion volume within several regions, including the right amygdala and anterior insula, each independently contributed to the error rate in recognition of individual emotions. Results provide additional support for a necessary role of the right amygdala and anterior insula within a network of regions underlying recognition of facial expressions, particularly those that have biological importance or motivational relevance and have implications for clinical practice.
Topics: Adult; Aged; Brain; Brain Mapping; Emotions; Facial Expression; Female; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Prosopagnosia; Stroke
PubMed: 29359308
DOI: 10.1055/s-0037-1608859 -
Cerebral Cortex (New York, N.Y. : 1991) May 2024We report an investigation of the neural processes involved in the processing of faces and objects of brain-lesioned patient PS, a well-documented case of pure acquired...
We report an investigation of the neural processes involved in the processing of faces and objects of brain-lesioned patient PS, a well-documented case of pure acquired prosopagnosia. We gathered a substantial dataset of high-density electrophysiological recordings from both PS and neurotypicals. Using representational similarity analysis, we produced time-resolved brain representations in a format that facilitates direct comparisons across time points, different individuals, and computational models. To understand how the lesions in PS's ventral stream affect the temporal evolution of her brain representations, we computed the temporal generalization of her brain representations. We uncovered that PS's early brain representations exhibit an unusual similarity to later representations, implying an excessive generalization of early visual patterns. To reveal the underlying computational deficits, we correlated PS' brain representations with those of deep neural networks (DNN). We found that the computations underlying PS' brain activity bore a closer resemblance to early layers of a visual DNN than those of controls. However, the brain representations in neurotypicals became more akin to those of the later layers of the model compared to PS. We confirmed PS's deficits in high-level brain representations by demonstrating that her brain representations exhibited less similarity with those of a DNN of semantics.
Topics: Humans; Prosopagnosia; Female; Adult; Brain; Neural Networks, Computer; Middle Aged; Pattern Recognition, Visual; Male; Models, Neurological
PubMed: 38795358
DOI: 10.1093/cercor/bhae211 -
Journal of Vision Aug 2019Despite extensive investigation, the causes and nature of developmental prosopagnosia (DP)-a severe face identification impairment in the absence of acquired brain...
Despite extensive investigation, the causes and nature of developmental prosopagnosia (DP)-a severe face identification impairment in the absence of acquired brain injury-remain poorly understood. Drawing on previous work showing that individuals identified as being neurotypical (NT) show robust individual differences in where they fixate on faces, and recognize faces best when the faces are presented at this location, we defined and tested four novel hypotheses for how atypical face-looking behavior and/or retinotopic face encoding could impair face recognition in DP: (a) fixating regions of poor information, (b) inconsistent saccadic targeting, (c) weak retinotopic tuning, and (d) fixating locations not matched to the individual's own face tuning. We found no support for the first three hypotheses, with NTs and DPs consistently fixating similar locations and showing similar retinotopic tuning of their face perception performance. However, in testing the fourth hypothesis, we found preliminary evidence for two distinct phenotypes of DP: (a) Subjects characterized by impaired face memory, typical face perception, and a preference to look high on the face, and (b) Subjects characterized by profound impairments to both face memory and perception and a preference to look very low on the face. Further, while all NTs and upper-looking DPs performed best when faces were presented near their preferred fixation location, this was not true for lower-looking DPs. These results suggest that face recognition deficits in a substantial proportion of people with DP may arise not from aberrant face gaze or compromised retinotopic tuning, but from the suboptimal matching of gaze to tuning.
Topics: Adult; Attention; Eye Movements; Facial Recognition; Female; Humans; Male; Middle Aged; Prosopagnosia; Saccades
PubMed: 31426085
DOI: 10.1167/19.9.7 -
Frontiers in Bioscience (Elite Edition) Jun 2014The goal of the current paper is to review recent findings concerning the neural basis of congenital prosopagnosia (CP), a lifelong impairment in face processing that... (Review)
Review
The goal of the current paper is to review recent findings concerning the neural basis of congenital prosopagnosia (CP), a lifelong impairment in face processing that occurs in the absence of explicit brain damage. As such, CP offers a unique model for exploring the psychological and neural bases of normal face processing. We start by providing background about face perception and representation, and then review behavioral evidence gleaned from individuals with CP. We then review recent functional and structural neural investigations which offer a comprehensive account of the mechanisms underlying CP and support a characterization of this impairment as a disconnection syndrome rather than as a syndrome related to focal brain malfunction. We end the paper by offering a general framework for CP which, we believe, best integrates the behavioral and neural findings, and offers a platform for generating hypotheses for future studies. There remain many open issues in our understanding of CP and, to address these unanswered questions, we lay out several future research directions and testable hypotheses for further investigation.
Topics: Brain; Face; Humans; Magnetic Resonance Imaging; Models, Neurological; Models, Psychological; Prosopagnosia; Recognition, Psychology
PubMed: 24896205
DOI: 10.2741/E705 -
Scientific Reports May 2017A wealth of evidence from behavioural, neuropsychological and neuroimaging research supports the view that face recognition is reliant upon a domain-specific network...
A wealth of evidence from behavioural, neuropsychological and neuroimaging research supports the view that face recognition is reliant upon a domain-specific network that does not process words. In contrast, the recent many-to-many model of visual recognition posits that brain areas involved in word and face recognition are functionally integrated. Developmental prosopagnosia (DP) is characterised by severe deficits in the recognition of faces, which the many-to-many model predicts should negatively affect word recognition. Alternatively, domain-specific accounts suggest that impairments in face and word processing need not go hand in hand. To test these possibilities, we ran a battery of 7 tasks examining word processing in a group of DP cases and controls. One of our prosopagnosia cases exhibited a severe reading impairment with delayed response times during reading aloud tasks, but not lexical decision tasks. Overall, however, we found no evidence of global word processing deficits in DP, consistent with a dissociation account for face and word processing.
Topics: Adult; Aged; Behavior; Female; Humans; Linguistics; Male; Middle Aged; Neuropsychological Tests; Prosopagnosia; Reading; Task Performance and Analysis; Visual Perception; Young Adult
PubMed: 28490791
DOI: 10.1038/s41598-017-01917-8