Imagery and perception in acquired prosopagnosia: Functional variants and their relation to structure.

Current models of face perception and the face-processing network suggest that acquired prosopagnosia may not be a single disorder but rather a family of variants differing in mechanism. It has been proposed that tests of face perception and face imagery can probe component processes to support apperceptive, associative, and amnestic distinctions. However, validating this proposal is hampered by the rarity of this condition.

The development of upright face perception depends on evolved orientation-specific mechanisms and experience.

Here we examine whether our impressive ability to perceive upright faces arises from evolved orientation-specific mechanisms, our extensive experience with upright faces, or both factors. To do so, we tested Claudio, a man with a congenital joint disorder causing his head to be rotated back so that it is positioned between his shoulder blades. As a result, Claudio has seen more faces reversed in orientation to his own face than matched to it.

Dissociations between face identity and face expression processing in developmental prosopagnosia.

Individuals with developmental prosopagnosia (DPs) experience severe and lifelong deficits recognising faces, but whether their deficits are selective to the processing of face identity or extend to the processing of face expression remains unclear. Clarifying this issue is important for understanding DP impairments and advancing theories of face processing. We compared identity and expression processing in a large sample of DPs (N = 124) using three different matching tasks that each assessed identity and expression processing with identical experimental formats.

Contralateral Biases in Category-selective Areas Are Stronger in the Left Hemisphere than the Right Hemisphere.

Contralateral bias is a well-known feature of early visual cortex, but how it varies across higher-level, category-selective visual cortex and how much that bias differs between preferred and nonpreferred is unclear. Here, we examined 12 category-selective regions across 4 experiments using peripherally presented faces, bodies, houses, and scenes, to measure the difference in contralateral bias between preferred and nonpreferred stimuli. The results showed a substantial range of contralateral biases across the category-selective regions, similar to prior studies using category-selective stimuli [Silson, E.

Persistent prosopagnosia following COVID-19.

COVID-19 can cause psychological problems including loss of smell and taste, long-lasting memory, speech, and language impairments, and psychosis. Here, we provide the first report of prosopagnosia following symptoms consistent with COVID-19. Annie is a 28-year-old woman who had normal face recognition prior to contracting COVID-19 in March 2020.

Music perception in acquired prosopagnosia.

Background: Acquired prosopagnosia is often associated with other deficits such as dyschromatopsia and topographagnosia, from damage to adjacent perceptual networks. A recent study showed that some subjects with developmental prosopagnosia also have congenital amusia, but problems with music perception have not been described with the acquired variant.

Objective: Our goal was to determine if music perception was also impaired in subjects with acquired prosopagnosia, and if so, its anatomic correlate.

Face distortions in prosopometamorphopsia provide new insights into the organization of face perception.

Prosopometamorphopsia (PMO) is a striking condition of visual perception in which facial features appear distorted, for example drooping, swelling, or twisting. Although numerous cases have been reported, few of those investigations have carried out formal testing motivated by theories of face perception. However, because PMO involves conscious visual distortions to faces which participants can report, it can be used to probe fundamental questions about face representations.

Hominoid-specific sulcal variability is related to face perception ability.

The relationship among brain structure, brain function, and behavior is of major interest in neuroscience, evolutionary biology, and psychology. This relationship is especially intriguing when considering hominoid-specific brain structures because they cannot be studied in widely examined models in neuroscience such as mice, marmosets, and macaques. The fusiform gyrus (FG) is a hominoid-specific structure critical for face processing that is abnormal in individuals with developmental prosopagnosia (DPs)-individuals who have severe deficits recognizing the faces of familiar people in the absence of brain damage.

Developmental prosopagnosics and super recognizers rely on the same facial features used by individuals with normal face recognition abilities for face identification.

Face recognition depends on the ability of the face processing system to extract facial features that define the identity of a face. In a recent study we discovered that altering a subset of facial features changed the identity of the face, indicating that they are critical for face identification. Changing another set of features did not change the identity of a face, indicating that they are not critical for face identification.

Face-Specific Perceptual Distortions Reveal A View- and Orientation-Independent Face Template.

The spatial coordinate system in which a stimulus representation is embedded is known as its reference frame. Every visual representation has a reference frame [1], and the visual system uses a variety of reference frames to efficiently code visual information [e.g.

Visual input to the left versus right eye yields differences in face preferences in 3-month-old infants.

From birth, infants prefer looking at faces over scrambled faces. This face input is important for the development of face processing: individuals who experienced early visual deprivation due to congenital cataracts have long-lasting face processing deficits. Interestingly, the deficits are eye-specific such that left eye cataracts disrupt the development of face processing, whereas right eye cataracts do not.

Eye movements and retinotopic tuning in developmental prosopagnosia.

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.

Object recognition in acquired and developmental prosopagnosia.

Whether face and object recognition are dissociated in prosopagnosia continues to be debated: a recent review highlighted deficiencies in prior studies regarding the evidence for such a dissociation. Our goal was to study cohorts with acquired and developmental prosopagnosia with a complementary battery of tests of object recognition that address prior limitations, as well as evaluating for residual effects of object expertise. We studied 15 subjects with acquired and 12 subjects with developmental prosopagnosia on three tests: the Old/New Tests, the Cambridge Bicycle Memory Test, and the Expertise-adjusted Test of Car Recognition.

Perception of musical pitch in developmental prosopagnosia.

Studies of developmental prosopagnosia have often shown that developmental prosopagnosia differentially affects human face processing over non-face object processing. However, little consideration has been given to whether this condition is associated with perceptual or sensorimotor impairments in other modalities. Comorbidities have played a role in theories of other developmental disorders such as dyslexia, but studies of developmental prosopagnosia have often focused on the nature of the visual recognition impairment despite evidence for widespread neural anomalies that might affect other sensorimotor systems.

Use of Face Information Varies Systematically From Developmental Prosopagnosics to Super-Recognizers.

Face-recognition abilities differ largely in the neurologically typical population. We examined how the use of information varies with face-recognition ability from developmental prosopagnosics to super-recognizers. Specifically, we investigated the use of facial features at different spatial scales in 112 individuals, including 5 developmental prosopagnosics and 8 super-recognizers, during an online famous-face-identification task using the bubbles method.

Greater reliance on the eye region predicts better face recognition ability.

Interest in using individual differences in face recognition ability to better understand the perceptual and cognitive mechanisms supporting face processing has grown substantially in recent years. The goal of this study was to determine how varying levels of face recognition ability are linked to changes in visual information extraction strategies in an identity recognition task. To address this question, fifty participants completed six tasks measuring face and object processing abilities.

Face-specific and domain-general visual processing deficits in children with developmental prosopagnosia.

Evidence suggests that face and object recognition depend on distinct neural circuitry within the visual system. Work with adults with developmental prosopagnosia (DP) demonstrates that some individuals have preserved object recognition despite severe face recognition deficits. This face selectivity in adults with DP indicates that face- and object-processing systems can develop independently, but it is unclear at what point in development these mechanisms are separable.

Word and text processing in developmental prosopagnosia.

The "many-to-many" hypothesis proposes that visual object processing is supported by distributed circuits that overlap for different object categories. For faces and words the hypothesis posits that both posterior fusiform regions contribute to both face and visual word perception and predicts that unilateral lesions impairing one will affect the other. However, studies testing this hypothesis have produced mixed results.

Localization and patterns of Cerebral dyschromatopsia: A study of subjects with prospagnosia.

Objective: Cerebral dyschromatopsia is sometimes associated with acquired prosopagnosia. Given the variability in structural lesions that cause acquired prosopagnosia, this study aimed to investigate the structural correlates of prosopagnosia-associated dyschromatopsia, and to determine if such colour processing deficits could also accompany developmental prosopagnosia. In addition, we studied whether cerebral dyschromatopsia is typified by a consistent pattern of hue impairments.

Seeing the eyes in acquired prosopagnosia.

Case reports have suggested that perception of the eye region may be impaired more than that of other facial regions in acquired prosopagnosia. However, it is unclear how frequently this occurs, whether such impairments are specific to a certain anatomic subtype of prosopagnosia, and whether these impairments are related to changes in the scanning of faces. We studied a large cohort of 11 subjects with this rare disorder, who had a variety of occipitotemporal or anterior temporal lesions, both unilateral and bilateral.

Getting lost: Topographic skills in acquired and developmental prosopagnosia.

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.

A Revised Neural Framework for Face Processing.

Face perception relies on computations carried out in face-selective cortical areas. These areas have been intensively investigated for two decades, and this work has been guided by an influential neural model suggested by Haxby and colleagues in 2000. Here, we review new findings about face-selective areas that suggest the need for modifications and additions to the Haxby model.

The processing of voice identity in developmental prosopagnosia.

Background: Developmental prosopagnosia is a disorder of face recognition that is believed to reflect impairments of visual mechanisms. However, voice recognition has rarely been evaluated in developmental prosopagnosia to clarify if it is modality-specific or part of a multi-modal person recognition syndrome.

Objective: Our goal was to examine whether voice discrimination and/or recognition are impaired in subjects with developmental prosopagnosia.