Processing Of Identity Research Articles

Concussion acutely disrupts auditory processing in division I football student-athletes

ABSTRACT Introduction Diagnosis, assessment, and management of sports-related concussion require a multi-modal approach. Yet, currently, an objective assessment of auditory processing is not included. The auditory system is uniquely complex, relying on exquisite temporal precision to integrate signals across many synapses, connected by long axons. Given this complexity and precision, together with the fact that axons are highly susceptible to damage from mechanical force, we hypothesize that auditory processing is susceptible to concussive injury. Methods We measured the frequency-following response (FFR), a scalp-recorded evoked potential that assesses processing of complex sound features, including pitch and phonetic identity. FFRs were obtained on male Division I Collegiate football players prior to contact practice to determine a pre-season baseline of auditory processing abilities, and again after sustaining a sports-related concussion. We predicted that concussion would decrease pitch and phonetic processing relative to the student-athlete’s preseason baseline. Results We found that pitch and phonetic encoding was smaller post-concussion. Student-athletes who sustained a second concussion showed similar declines after each injury. Conclusions Auditory processing should be included in the multimodal assessment of sports-related concussion. Future studies that extend this work to other sports, other injuries (e.g. blast exposure), and to female athletes are needed.

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. We ran each task in upright and inverted orientations and we measured inversion effects to assess the integrity of upright-specific face processes. We report three main results. First, DPs showed large deficits at discriminating identity but only subtle deficits at discriminating expression. Second, DPs showed a reduced inversion effect for identity but a normal inversion effect for expression. Third, DPs' performance on the expression tasks were linked to autism traits, but their performance on the identity tasks were not. These results constitute several dissociations between identity and expression processing in DP, and they are consistent with the view that the core impairment in DP is highly selective to identity.

Attention Modulates the Role of Speakers' Voice Identity and Linguistic Information in Spoken Word Processing: Evidence From Event-Related Potentials.

The human voice usually contains two types of information: linguistic and identity information. However, whether and how linguistic information interacts with identity information remains controversial. This study aimed to explore the processing of identity and linguistic information during spoken word processing by considering the modulation of attention. We conducted two event-related potentials (ERPs) experiments in the study. Different speakers (self, friend, and unfamiliar speakers) and emotional words (positive, negative, and neutral words) were used to manipulate the identity and linguistic information. With the manipulation, Experiment 1 explored the identity and linguistic information processing with a word decision task that requires participants' explicit attention to linguistic information. Experiment 2 further investigated the issue with a passive oddball paradigm that requires rare attention to either the identity or linguistic information. Experiment 1 revealed an interaction among speaker, word type, and hemisphere in N400 amplitudes but not in N100 and P200, which suggests that identity information interacted with linguistic information at the later stage of spoken word processing. The mismatch negativity results of Experiment 2 showed no significant interaction between speaker and word pair, which indicates that identity and linguistic information were processed independently. The identity information would interact with linguistic information during spoken word processing. However, the interaction was modulated by the task demands on attention involvement. We propose an attention-modulated explanation to explain the mechanism underlying identity and linguistic information processing. Implications of our findings are discussed in light of the integration and independence theories.

Equivalent processing of facial expression and identity by macaque visual system and task-optimized neural network

Both the primate visual system and artificial deep neural network (DNN) models show an extraordinary ability to simultaneously classify facial expression and identity. However, the neural computations underlying the two systems are unclear. Here, we developed a multi-task DNN model that optimally classified both monkey facial expressions and identities. By comparing the fMRI neural representations of the macaque visual cortex with the best-performing DNN model, we found that both systems: (1) share initial stages for processing low-level face features which segregate into separate branches at later stages for processing facial expression and identity respectively, and (2) gain more specificity for the processing of either facial expression or identity as one progresses along each branch towards higher stages. Correspondence analysis between the DNN and monkey visual areas revealed that the amygdala and anterior fundus face patch (AF) matched well with later layers of the DNN's facial expression branch, while the anterior medial face patch (AM) matched well with later layers of the DNN's facial identity branch. Our results highlight the anatomical and functional similarities between macaque visual system and DNN model, suggesting a common mechanism between the two systems.

Distinct Neural Resource Involvements but Similar Hemispheric Lateralization Patterns in Pre-Attentive Processing of Speaker's Identity and Linguistic Information.

The speaker's identity (who the speaker is) and linguistic information (what the speaker is saying) are essential to daily communication. However, it is unclear whether and how listeners process the two types of information differently in speech perception. The present study adopted a passive oddball paradigm to compare the identity and linguistic information processing concerning neural resource involvements and hemispheric lateralization patterns. We used two female native Mandarin speakers' real and pseudo-Mandarin words to differentiate the identity from linguistic (phonological and lexical) information. The results showed that, in real words, the phonological-lexical variation elicited larger MMN amplitudes than the identity variation. In contrast, there were no significant MMN amplitude differences between the identity and phonological variation in pseudo words. Regardless of real or pseudo words, the identity and linguistic variation did not elicit MMN amplitudes differences between the left and right hemispheres. Taken together, findings from the present study indicated that the identity information recruited similar neural resources to the phonological information but different neural resources from the lexical information. However, the identity and linguistic information processing did not show a particular hemispheric lateralization pattern at an early pre-attentive speech perception stage. The findings revealed similarities and differences between linguistic and non-linguistic information processing, contributing to a better understanding of speech perception and spoken word recognition.

Multielectrode recordings of cockroach antennal lobe neurons in response to temporal dynamics of odor concentrations

The initial representation of the instantaneous temporal information about food odor concentration in the primary olfactory center, the antennal lobe, was examined by simultaneously recording the activity of antagonistic ON and OFF neurons with 4-channel tetrodes. During presentation of pulse-like concentration changes, ON neurons encode the rapid concentration increase at pulse onset and the pulse duration, and OFF neurons the rapid concentration decrease at pulse offset and the duration of the pulse interval. A group of ON neurons establish a concentration-invariant representation of odor pulses. The responses of ON and OFF neurons to oscillating changes in odor concentration are determined by the rate of change in dependence on the duration of the oscillation period. By adjusting sensitivity for fluctuating concentrations, these neurons improve the representation of the rate of the changing concentration. In other ON and OFF neurons, the response to changing concentrations is invariant to large variations in the rate of change due to variations in the oscillation period, facilitating odor identification in the antennal-lobe. The independent processing of odor identity and the temporal dynamics of odor concentration may speed up processing time and improve behavioral performance associated with plume tracking, especially when the air is not moving.

The topic of memory and identity in contemporary Ukrainian prose

The relevance of the study is determined by the need to highlight the issues of memory and identity in the context of globalization, decolonization, the escalation of the Russian-Ukrainian war, and the intensification of the search for national and individual identity, particularly through the means of literature. The object of the research is Ukrainian prose of the beginning of the 21st century, which records memory and raises the issues of identity and historical continuity. The epic dimension of the problem is most fully represented by such novels as “Oblivion” by Tania Maliarchuk, “Amadoka” by Sofiіa Andrukhovych, and “Beech Land” by Maria Matios. The subject of the research is individual and group memory and identity, at one time artificially displaced from the national narrative and deliberately interrupted by the dictatorial Soviet-Russian regime. The study aims to investigate the artistic reconstruction of the memory and identity of Ukrainians in national literature of the beginning of the 21st century, to find out the instrumentalization of memory meanings and the role of remembering/forgetting. As a result of the research, using the hermeneutic method, we trace the artistic interpretation of memory in the context of an intensive understanding of the place and role of Ukrainians in the unfolding of the plot of history, returning to them a sense of individuality, and simply uniqueness, integrality, and durability (that is, permanence). Tania Maliarchuk’s novel “Oblivion” tells about the memory and place of modern man in the post-colonial Ukrainian space, about his awareness of the connection and continuity of the past, present, and future. Sofiіa Andrukhovych's novel “Amadoka” deals with the history of four generations of different eras and is united by the theme of the rupture of memory, tradition, time, and space. A successful attempt at positive processing of memory and identity based on the material of the history of Bukovyna in the 18th–21st centuries was performed by Maria Matios in the novel “Beech Land”. In addition to the common goal of exposing the Soviet pseudo-memory and (re)nourishing specific Ukrainian identity, the authors raise issues of regional specificity of public perception and debunking Soviet-Russian myths about the USSR. The prospects of research on the topic of memory and identity are reproductions of the entire range of semantic resources encoded in Ukrainian literature. This can become a way to escape from the power of the myths of the Russian Empire.

Happy face advantage disappears in Chinese context: The constancy of holistic processing for emotional faces

It is well documented that facial identity is processed in a holistic manner. Chen & Cheung (2021) recently found that happy faces evoked a larger holistic face processing than angry faces in Caucasian context. Here we adopted the complete composite face paradigm to investigate how facial emotion influenced holistic processing of facial identity in Chinese context. In Experiment 1, we used Chinese faces with happy, neutral and surprise emotion. Participants judged whether the top halves of the two successively presented composite faces were same or different, while their facial emotion was always consistent in a trial. We found equal composite face effects (CFE) for the three emotional faces. In Experiment 2, either top halves or bottom halves were judged, and angry, happy, fearful and neutral faces were compared. Results showed that although judging the top half induced a larger CFE than judging the bottom half, the CFE was equal among four emotional faces. In Experiment 3, angry and happy faces with high/low emotional intensity were further compared. We also found equal CFE for angry and happy faces, which was not modulated by the emotional intensity. These results indicated that the holistic processing of facial identity is robust and constant regardless of emotion categories and emotion intensity in Chinese context. The relation between cultural difference and holistic processing of emotional faces should be considered in the future.

Does Changing the Font Type Affect the Processing of Words Written in Cyrillic and Latin Alphabet?

To understand the reading process, it is necessary to explore the mechanisms of visual word recognition. The basic level of that recognition is the processing of letters, their size and visual identity. The specificity of the Serbian language is characterized by the parallel use of two alphabetic systems – Latin and Cyrillic, which contain a number of common, but also their own unique letters. Since some of the differences between the fonts are based on visual specific aditions at the end of letter's lines, there is also a significant contribution of fonts in letter recognition and reading. The main goal of this study is to examine the effect of font type on the processing of Latin and Cyrillic words. The aim was also to examine the effect of letter degradation on the word processing in these two alphabetic systems. The study included two experiments with Latin and Cyrillic words written in lowercase and uppercase. Participants were 221 students from the University of Banja Luka. Three factors were varied in both experiments: alphabet, “visual availability” (which refers to the visibility of words after degradation), and font type. Two analyses were performed ANOVA by subject (F1 analysis) and ANOVA by item (F2 analysis). Results show that there is a main effect of visual availability on processing speed of words. Visual degradation has slowed reaction time, but this effect is not the same in Latin and Cyrillic words. Significant interaction of font and alphabet is confirmed only in F2 analysis, so these results have limited validity. This study also revealed differences between lowercase and uppercase. Degradation of lowercase was more detrimental that degradation of uppercase. The obtained results indicate that word processing in two alphabetic systems can be partly explained by the visual characteristics and grapheme structure of their letters.

Understanding the Impact of Face Masks on the Processing of Facial Identity, Emotion, Age, and Gender.

The COVID-19 pandemic has introduced new challenges for governments and individuals. Unprecedented efforts at reducing virus transmission launched a novel arena for human face recognition in which faces are partially occluded with masks. Previous studies have shown that masks decrease accuracy of face identity and emotion recognition. The current study focuses on the impact of masks on the speed of processing of these and other important social dimensions. Here we provide a systematic assessment of the impact of COVID-19 masks on facial identity, emotion, gender, and age. Four experiments (N = 116) were conducted in which participants categorized faces on a predefined dimension (e.g., emotion). Both speed and accuracy were measured. The results revealed that masks hindered the perception of virtually all tested facial dimensions (i.e., emotion, gender, age, and identity), interfering with normal speed and accuracy of categorization. We also found that the unwarranted effects of masks were not due to holistic processes, because the Face Inversion Effect (FIE) was generally not larger with unmasked compared with masked faces. Moreover, we found that the impact of masks is not automatic and that under some contexts observers can control at least part of their detrimental effects.

Holistic Face Processing: Eye Movement Analysis

Holistic processing is a hallmark of face perception and has been observed separately for facial identity and expression. While the identity of a face remains constant regardless of any changes in facial expressions, to what extent is holistic processing of facial identity affected by task-irrelevant facial expressions? If holistic processing is flexible and integrates both identity and expression information, the magnitude of holistic processing of facial identity may be systematically modulated by different facial expressions, due to either visual or emotional differences among the expressions. In Experiment 1, participants matched the identities of target halves of two sequentially presented face composites, with both composites showing either positive (happy) or negative (angry) expressions. The presentation duration for the test composite was either short (200 ms) or long (until a response). With a short presentation duration, the magnitude of holistic processing of identity for happy and angry composites was comparable. In contrast, with a long presentation duration, holistic processing of identity was reduced for angry compared with happy face composites. Experiment 2 replicated the results and showed reduced holistic processing of identity for face composites with either angry or neutral expressions, compared with happy expressions, given a long presentation duration. Because the modulation of facial expressions on holistic processing of facial identity was observed with long, but not short, presentation durations, these results suggest that such influence is unlikely solely due to visual differences, but may instead arise from cognitive evaluation of the emotions conveyed by facial expressions.

Joint encoding of facial identity, orientation, gaze, and expression in the middle dorsal face area

The last two decades have established that a network of face-selective areas in the temporal lobe of macaque monkeys supports the visual processing of faces. Each area within the network contains a large fraction of face-selective cells. And each area encodes facial identity and head orientation differently. A recent brain-imaging study discovered an area outside of this network selective for naturalistic facial motion, the middle dorsal (MD) face area. This finding offers the opportunity to determine whether coding principles revealed inside the core network would generalize to face areas outside the core network. We investigated the encoding of static faces and objects, facial identity, and head orientation, dimensions which had been studied in multiple areas of the core face-processing network before, as well as facial expressions and gaze. We found that MD populations form a face-selective cluster with a degree of selectivity comparable to that of areas in the core face-processing network. MD encodes facial identity robustly across changes in head orientation and expression, it encodes head orientation robustly against changes in identity and expression, and it encodes expression robustly across changes in identity and head orientation. These three dimensions are encoded in a separable manner. Furthermore, MD also encodes the direction of gaze in addition to head orientation. Thus, MD encodes both structural properties (identity) and changeable ones (expression and gaze) and thus provides information about another animal's direction of attention (head orientation and gaze). MD contains a heterogeneous population of cells that establish a multidimensional code for faces.

Associations with monetary values do not influence access to awareness for faces.

Human faces can convey socially relevant information in various ways. Since the early detection of such information is crucial in social contexts, socially meaningful information might also have privileged access to awareness. This is indeed suggested by previous research using faces with emotional expressions. However, the social relevance of emotional faces is confounded with their physical stimulus characteristics. Here, we sought to overcome this problem by manipulating the relevance of face stimuli through classical conditioning: Participants had to learn the association between different face exemplars and high or low amounts of positive and negative monetary outcomes. Before and after the conditioning procedure, the time these faces needed to enter awareness was probed using continuous flash suppression, a variant of binocular rivalry. While participants successfully learned the association between the face stimuli and the respective monetary outcomes, faces with a high monetary value did not enter visual awareness faster than faces with a low monetary value after conditioning, neither for rewarding nor for aversive outcomes. Our results tentatively suggest that behaviorally relevant faces do not have privileged access to awareness when the assessment of the faces’ relevance is dependent on the processing of face identity, as this requires complex stimulus processing that is likely limited at pre-conscious stages.

Fetal Alcohol Exposure Alters BOLD Activation Patterns in Brain Regions Mediating the Interpretation of Facial Affect.

Although deficits in the interpretation of affective facial expressions have been described clinically and in behavioral studies of fetal alcohol spectrum disorders (FASD), effects of prenatal alcohol exposure on the neural networks that mediate affective appraisal have not previously been examined. We administered a nonverbal event-related fMRI affective appraisal paradigm to 64 children (mean age=12.5years; 18 with fetal alcohol syndrome (FAS) or partial FAS (PFAS), 18 nonsyndromal heavily exposed (HE), and 28 controls). Happy, sad, angry, fearful, and neutral faces and pixelated control images were presented sequentially in a randomized order. The child indicated whether the currently displayed face showed the same or different affect as the previous one. Data from whole-brain analyses showed that all groups activated the appropriate face processing neural networks. Region of interest analyses indicated that, compared to HE and control children, the FAS/PFAS group exhibited greater blood oxygenation level-dependent (BOLD) signal changes when processing neutral faces than pixelated images in 2 regions that form part of the visual sensory social brain network, which plays an important role in the initial processing of facial affect. By contrast, BOLD signal when processing angry faces was weaker for the FAS/PFAS group in a region involved in the processing of facial identity and facial expressions and in a region involved in the recognition and selection of behavioral responses to aggressive behavior. These findings of greater BOLD signal in the FAS/PFAS group in response to neutral faces suggest less efficient neural processing of more difficult to interpret emotions, and the weaker BOLD response to angry faces suggests altered processing of angry stimuli. Although behavioral performance did not differ in this relatively simple affective appraisal task, these data suggest that in children with FAS and PFAS, the appraisal of neutral affect and anger is likely to be more effortful in more challenging and dynamic social contexts.

Neural processing of facial identity and expression in adults with and without autism: A multi-method approach

The ability to recognize faces and facial expressions is a common human talent. It has, however, been suggested to be impaired in individuals with autism spectrum disorder (ASD). The goal of this study was to compare the processing of facial identity and emotion between individuals with ASD and neurotypicals (NTs).Behavioural and functional magnetic resonance imaging (fMRI) data from 46 young adults (aged 17–23 years, NASD = 22, NNT = 24) was analysed. During fMRI data acquisition, participants discriminated between short clips of a face transitioning from a neutral to an emotional expression. Stimuli included four identities and six emotions. We performed behavioural, univariate, multi-voxel, adaptation and functional connectivity analyses to investigate potential group differences.The ASD-group did not differ from the NT-group on behavioural identity and expression processing tasks. At the neural level, we found no differences in average neural activation, neural activation patterns and neural adaptation to faces in face-related brain regions. In terms of functional connectivity, we found that amygdala seems to be more strongly connected to inferior occipital cortex and V1 in individuals with ASD. Overall, the findings indicate that neural representations of facial identity and expression have a similar quality in individuals with and without ASD, but some regions containing these representations are connected differently in the extended face processing network.

Normal recognition of famous voices in developmental prosopagnosia

Developmental prosopagnosia (DP) is a condition characterised by lifelong face recognition difficulties. Recent neuroimaging findings suggest that DP may be associated with aberrant structure and function in multimodal regions of cortex implicated in the processing of both facial and vocal identity. These findings suggest that both facial and vocal recognition may be impaired in DP. To test this possibility, we compared the performance of 22 DPs and a group of typical controls, on closely matched tasks that assessed famous face and famous voice recognition ability. As expected, the DPs showed severe impairment on the face recognition task, relative to typical controls. In contrast, however, the DPs and controls identified a similar number of voices. Despite evidence of interactions between facial and vocal processing, these findings suggest some degree of dissociation between the two processing pathways, whereby one can be impaired while the other develops typically. A possible explanation for this dissociation in DP could be that the deficit originates in the early perceptual encoding of face structure, rather than at later, post-perceptual stages of face identity processing, which may be more likely to involve interactions with other modalities.

Many exposures to a real-world object without knowing the details: The focus of attention does not include entire objects but only the relevant level of abstraction

Participants frequently fail to remember information (e.g., the identity of a letter) immediately after seemingly processing it (finding the letter in a set of numbers to report its color; Chen & Wyble, 2015). This appears to pose a challenge to the common assumption that an item in the focus of attention is processed and therefore remembered a few seconds later. Chen and Wyble argue that the target identity is encoded but not consolidated into memory, however we have recently suggested that there may be a failure of encoding: some category information is so automatically accessible, identity never needs to be accessed or encoded at all. For example, while membership of the category ‘letter’ may be automatically assessed, membership of category ‘letter from 1st half of the alphabet’ almost certainly requires processing of identity. Consistent with this, we find that in the latter condition, participants accurately remember letter identity, suggesting that when identity is necessary for target identification it is encoded and consolidated into memory. The current study extends these findings to an investigation of the commonly demonstrated long-term memory-based amnesia for details of the US penny (Nickerson, 1979). On every trial, people searched for and found a penny. When participants looked for this penny target among real coin distractors, they had amnesia for penny details (on two surprise trials), despite having seen it thousands of times previously and having searched for it actively on a dozen proceeding trials. However, when fake pennies were included as distractors, this amnesia disappeared. These results argue that the focus of attention is not all-or-none: we can look at and process a penny or a letter, but we do not by necessity process the entire object when we do so. The information required for report causes different levels of processing of the exact same object.

Flexible face processing: Holistic processing of facial identity is modulated by task-irrelevant facial expression

Holistic processing is a hallmark of face perception and has been observed separately for facial identity and expression. While the identity of a face remains constant regardless of any changes in facial expressions, to what extent is holistic processing of facial identity affected by task-irrelevant facial expressions? If holistic processing is flexible and integrates both identity and expression information, the magnitude of holistic processing of facial identity may be systematically modulated by different facial expressions, due to either visual or emotional differences among the expressions. In Experiment 1, participants matched the identities of target halves of two sequentially presented face composites, with both composites showing either positive (happy) or negative (angry) expressions. The presentation duration for the test composite was either short (200 ms) or long (until a response). With a short presentation duration, the magnitude of holistic processing of identity for happy and angry composites was comparable. In contrast, with a long presentation duration, holistic processing of identity was reduced for angry compared with happy face composites. Experiment 2 replicated the results and showed reduced holistic processing of identity for face composites with either angry or neutral expressions, compared with happy expressions, given a long presentation duration. Because the modulation of facial expressions on holistic processing of facial identity was observed with long, but not short, presentation durations, these results suggest that such influence is unlikely solely due to visual differences, but may instead arise from cognitive evaluation of the emotions conveyed by facial expressions.

Neural responses in a fast periodic visual stimulation paradigm reveal domain-general visual discrimination deficits in developmental prosopagnosia

We investigated selective impairments of visual identity discrimination in developmental prosopagnosia (DP), using a fast periodic identity oddball stimulation paradigm with electroencephalography (EEG). In Experiment 1, neural responses to unfamiliar face identity changes were strongly attenuated for individuals with DP as compared to Control participants, to the same extent for upright and inverted faces. This reduction of face identity discrimination responses, which was confirmed in Experiment 2, provides direct evidence for deficits in the visual processing of unfamiliar facial identity in DP. Importantly, Experiment 2 demonstrated that DPs showed attenuated neural responses to identity oddballs not only with face images, but also with non-face images (cars). This result strongly suggests that rapid identity-related visual processing impairments in DP are not restricted to faces, but also affect familiar classes of non-face stimuli. Visual discrimination deficits in DP do not appear to be face-specific. To account for these findings, we propose a new account of DP as a domain-general deficit in rapid visual discrimination.

Holistic processing of facial identity in developmental prosopagnosia

The nature of the perceptual deficit seen in developmental prosopagnosia remains poorly understood. One possibility is that these individuals experience face recognition difficulties because they fail to process faces holistically; they may be less able to analyze distal regions in parallel and therefore struggle to integrate information from different regions into a unified perceptual whole. Consequently, developmental prosopagnosics may be forced to base perceptual decisions on a slow, effortful piecemeal analysis of local facial features. In the present study, we sought to test this view by comparing the face recognition of developmental prosopagnosics and typical observers under two viewing conditions: when target faces were briefly presented in their entirety, and when they were inspected region-by-region through a dynamic aperture. If developmental prosopagnosics are forced to base perceptual decisions on information accumulated from a serial piecemeal analysis, one would expect little if any decrement in performance when target faces are viewed through apertures. Contrary to this prediction, however, developmental prosopagnosics showed strong aperture effects comparable with typical observers; their perceptual decisions were more accurate in the whole-face condition than when targets were viewed through the aperture. As expected, the developmental prosopagnosics were less accurate than typical controls when judging briefly presented faces shown in their entirety. Strikingly, however, they were also less able to accumulate perceptual evidence from a serial region-by-region analysis, than typical observers. Our results suggest that the perceptual problems seen in this population arise from imprecise descriptions of local regions, not aberrant holistic processing.