Late Component Research Articles

Overt and covert attention shifts to emotional faces: Combining EEG, eye tracking, and a go/no-go paradigm.

In everyday life, faces with emotional expressions quickly attract attention and eye movements. To study the neural mechanisms of such emotion-driven attention by means of event-related brain potentials (ERPs), tasks that employ covert shifts of attention are commonly used, in which participants need to inhibit natural eye movements towards stimuli. It remains, however, unclear how shifts of attention to emotional faces with and without eye movements differ from each other. The current preregistered study aimed to investigate neural differences between covert and overt emotion-driven attention. We combined eye tracking with measurements of ERPs to compare shifts of attention to faces with happy, angry, or neutral expressions when eye movements were either executed (go conditions) or withheld (no-go conditions). Happy and angry faces led to larger EPN amplitudes, shorter latencies of the P1 component, and faster saccades, suggesting that emotional expressions significantly affected shifts of attention. Several ERPs (N170, EPN, LPC) were augmented in amplitude when attention was shifted with an eye movement, indicating an enhanced neural processing of faces if eye movements had to be executed together with a reallocation of attention. However, the modulation of ERPs by facial expressions did not differ between the go and no-go conditions, suggesting that emotional content enhances both covert and overt shifts of attention. In summary, our results indicate that overt and covert attention shifts differ but are comparably affected by emotional content.

Improved spatialization performance for joint speech dereverberation and noise reduction in binaural hearing aids

ObjectiveIn this work we propose a unified solution for joint speech dereverberation, noise reduction and spatial preservation of either diffuse noise fields or single-point noise sources in binaural hearing aid applications, which is based on the multichannel Wiener filter (MWF) with preservation of the interaural coherence (MWF-IC) method. MethodsThe original interaural coherence (IC) auxiliary penalty cost function in the MWF-IC, which comprises information about both interfering noise and late reverberation component, is modified to consider the interference noise information only. It provides a new regularization form for preserving both interaural time difference (ITD) and IC binaural cues of the residual noise. This approach is theoretically supported by recent findings about the relationship between IC and ITD binaural cues for point acoustic sources. ResultsExtensive simulation results with objective measures, as well as psychoacoustic experiments with normal hearing volunteers indicate that the proposed method outperforms the preservation of spatial localization cues of its original version, keeping approximately the same performance in terms of noise-reduction and speech-dereverberation. ConclusionThe proposed scheme expands the MWF-IC original spatial cue preservation capability from only diffuse noise fields to either diffuse noise fields or a single-point noise source. SignificanceThis is the first MWF-based speech dereverberation and noise reduction method for binaural hearing aid that provides perceptually relevant preservation of acoustic scenarios comprised of one speech source and either a single-point noise source or a diffuse noise field.

ESCRT components ISTL1 andLIP5 are required for tapetal function and pollen viability.

Pollen wall assembly is crucial for pollen development and plant fertility. The durable biopolymer sporopollenin and the constituents of the tryphine coat are delivered to developing pollen grains by the highly coordinated secretory activity of the surrounding tapetal cells. The role of membrane trafficking in this process, however, is largely unknown. In this study, we used Arabidopsis thaliana to characterize the role of two late-acting endosomal sorting complex required for transport (ESCRT) components, ISTL1 and LIP5, in tapetal function. Plants lacking ISTL1 and LIP5 form pollen with aberrant exine patterns, leading to partial pollen lethality. We found that ISTL1 and LIP5 are required for exocytosis of plasma membrane and secreted proteins in the tapetal cells at the free microspore stage, contributing to pollen wall development and tryphine deposition. Whereas the ESCRT machinery is well known for its role in endosomal trafficking, the function of ISTL1 and LIP5 in exocytosis is not a typical ESCRT function. The istl1 lip5 double mutants also show reduced intralumenal vesicle concatenation in multivesicular endosomes in both tapetal cells and developing pollen grains as well as morphological defects in early endosomes/trans-Golgi networks, suggesting that late ESCRT components function in the early endosomal pathway and exocytosis.

Auditory brainstem response asymmetries in older adults: An exploratory study using click and speech stimuli.

BackgroundSome evidence suggests that young adults exhibit a selective laterality of auditory brainstem response (ABR) elicited with speech stimuli. Little is known about such an auditory laterality in older adults.ObjectiveThe aim of this study was to investigate possible asymmetric auditory brainstem processing between right and left ear presentation in older adults.MethodsSixty-two older adults presenting with normal hearing thresholds according to their age and who were native speakers of Quebec French participated in this study. ABR was recorded using click and a 40-ms /da/ syllable. ABR was elicited through monaural right and monaural left stimulation. Latency and amplitude for click-and speech-ABR components were compared between right and left ear presentations. In addition, for the /da/ syllable, a fast Fourier transform analysis of the sustained frequency-following response (FFR) of the vowel was performed along with stimulus-to-response and right-left ear correlation analyses.ResultsNo significant differences between right and left ear presentation were found for amplitudes and latencies of the click-ABR components. Significantly shorter latencies for right ear presentation as compared to left ear presentation were observed for onset and offset transient components (V, A and O), sustained components (D and E), and voiced transition components (C) of the speech-ABR. In addition, the spectral amplitude of the fundamental frequency (F0) was significantly larger for the left ear presentation than the right ear presentation.ConclusionsResults of this study show that older adults with normal hearing exhibit symmetric encoding for click stimuli at the brainstem level between the right and left ear presentation. However, they present with brainstem asymmetries for the encoding of selective stimulus components of the speech-ABR between the right and left ear presentation. The right ear presentation of a /da/ syllable elicited reduced neural timing for both transient and sustained components compared to the left ear. Conversely, a stronger left ear F0 encoding was observed. These findings suggest that at a preattentive, sensory stage of auditory processing, older adults lateralize speech stimuli similarly to young adults.

Valence-dependent Neural Correlates of Augmented Feedback Processing in Extensive Motor Sequence Learning – Part I: Practice-related Changes of Feedback Processing

Several event-related potentials (ERPs) are associated with the processing of valence-dependent augmented feedback during the practice of motor tasks. In this study, 38 students learned a sequential arm-movement-task with 192 trials in each of five practice sessions (960 practice trials in total), to examine practice-related changes in neural feedback processing. Electroencephalogram (EEG) was recorded in the first and last practice session. An adaptive bandwidth for movement accuracy led to equal amounts of positive and negative feedback. A frontal located negative deflection in the time window of the feedback-related negativity (FRN) was more negative for negative feedback and might reflect reward prediction errors in reinforcement learning. This negativity increased after extensive practice, which might indicate that smaller errors are harder to identify in the later phase. The late fronto-central positivity (LFCP) was more positive for negative feedback and is assumed to be associated with supervised learning and behavioral adaptations based on feedback with higher complexity. No practice-related changes of the LFCP were observed, which suggests that complex feedback is processed independent from the practice phase. The P300 displayed a more positive activation for positive feedback, which might be interpreted as the higher significance of positive feedback for the updating of internal models in this setting. A valence-independent increase of the P300 amplitude after practice might reflect an improved ability to update the internal representation based on feedback information. These results demonstrate that valence-dependent neural feedback processing changes with extensive practice of a novel motor task. Dissociating changes in latencies of different components support the assumption that they are related to distinct mechanisms of feedback-dependent learning.

The surface brightness–colour relations based on eclipsing binary stars and calibrated withGaiaEDR3

Aims.The surface brightness–colour relation (SBCR) is a basic tool for establishing precise and accurate distances within the Local Group. Detached eclipsing binary stars with accurately determined radii and trigonometric parallaxes allow calibration of the SBCRs with unprecedented accuracy.Methods.We analysed four nearby eclipsing binary stars containing late F-type main sequence components: AL Ari, AL Dor, FM Leo, and BN Scl. We determined very precise spectroscopic orbits and combined them with high-precision ground- and space-based photometry. We derived the astrophysical parameters of their components with mean errors of 0.1% for mass and 0.4% for radius. We combined those four systems with another 24 nearby eclipsing binaries with accurately known radii from the literature for whichGaiaEDR3 parallaxes are available in order to derive the SBCRs.Results.The resulting SBCRs cover stellar spectral types from B9 V to G7 V. For calibrations, we used Johnson opticalBandV,GaiaGBPandG, and 2MASSJHKbands. The most precise relations are calibrated using the infraredKband and allow angular diameters of A-, F-, and G-type dwarf and subgiant stars to be predicted with a precision of 1%.

The Dynamic Differences between Self- and Other-Oriented Mental Inferences: An ERP Study on a False-Belief Task.

Theory of mind (ToM) refers to the ability to infer others' mental states. In our everyday lives, we need to interact constantly and appropriately with others. Not only is ToM involved in understanding others' mental states (other-oriented mental inferences), but it also helps to keep our own mental states (self-oriented mental inferences). In this study, we designed a false-belief task using event-related potential (ERP) measures to investigate the dynamic differences between the two types of mental inferences. In the false-belief task, participants were prompted with a cue to attribute a belief to either themselves (self-oriented) or another person (other-oriented). Results showed that other-oriented false-belief attribution elicited a larger late positive component (LPC; 320~440 ms post-cue onset) than the one elicited by self-oriented attribution at bilateral parieto-occipital electrodes, and also a larger late negative component (LNC; 380~500 ms post-cue onset) at frontal-central electrodes. In addition, the difference in amplitude of LPC between the two types of false-belief attribution was positively correlated with self-reported autistic traits measured by the Autism Spectrum Quotient (AQ). Based on prior literature, we propose that the LPC and LNC reflect the processes of self-other distinction and conflict control, respectively. Moreover, the difficulty in distinguishing other from the self is related to one's degree of autistic traits.

Visual evoked potential latency predicts cognitive function in people with multiple sclerosis.

Prior studies have reported an association between visual evoked potentials (VEPs) and cognitive performance in people with multiple sclerosis (PwMS), but the specific mechanisms that account for this relationship remain unclear. We examined the relationship between VEP latency and cognitive performance in a large sample of PwMS, hypothesizing that VEP latency indexes not only visual system functioning but also general neural efficiency. Standardized performance index scores were obtained for the domains of memory, executive function, visual-spatial processing, verbal function, attention, information processing speed, and motor skills, as well as global cognitive performance (NeuroTrax battery). VEP P100 component latency was obtained using a standard checkerboard pattern-reversal paradigm. Prolonged VEP latency was significantly associated with poorer performance in multiple cognitive domains, and with the number of cognitive domains in which performance was ≥ 1 SD below the normative mean. Relationships between VEP latency and cognitive performance were significant for information processing speed, executive function, attention, motor skills, and global cognitive performance after controlling for disease duration, visual acuity, and inter-ocular latency differences. This study provides evidence that VEP latency delays index general neural inefficiency that is associated with cognitive disturbances in PwMS.

Cortical monitoring of cardiac activity during rapid eye movement sleep: the heartbeat evoked potential in phasic and tonic rapid-eye-movement microstates.

Sleep is a fundamental physiological state that facilitates neural recovery during periods of attenuated sensory processing. On the other hand, mammalian sleep is also characterized by the interplay between periods of increased sleep depth and environmental alertness. Whereas the heterogeneity of microstates during non-rapid-eye-movement (NREM) sleep was extensively studied in the last decades, transient microstates during rapid-eye-movement (REM) sleep received less attention. REM sleep features two distinct microstates: phasic and tonic. Previous studies indicate that sensory processing is largely diminished during phasic REM periods, whereas environmental alertness is partially reinstated when the brain switches into tonic REM sleep. Here, we investigated interoceptive processing as quantified by the heartbeat evoked potential (HEP) during REM microstates. We contrasted the HEPs of phasic and tonic REM periods using two separate databases that included the nighttime polysomnographic recordings of healthy young individuals (N = 20 and N = 19). We find a differential HEP modulation of a late HEP component (after 500 ms post-R-peak) between tonic and phasic REM. Moreover, the late tonic HEP component resembled the HEP found in resting wakefulness. Our results indicate that interoception with respect to cardiac signals is not uniform across REM microstates, and suggest that interoceptive processing is partially reinstated during tonic REM periods. The analyses of the HEP during REM sleep may shed new light on the organization and putative function of REM microstates.

Comparison of Scalp ERP to Faces in Macaques and Humans.

Face recognition is an essential activity of social living, common to many primate species. Underlying processes in the brain have been investigated using various techniques and compared between species. Functional imaging studies have shown face-selective cortical regions and their degree of correspondence across species. However, the temporal dynamics of face processing, particularly processing speed, are likely different between them. Across sensory modalities activation of primary sensory cortices in macaque monkeys occurs at about 3/5 the latency of corresponding activation in humans, though this human simian difference may diminish or disappear in higher cortical regions. We recorded scalp event-related potentials (ERPs) to presentation of faces in macaques and estimated the peak latency of ERP components. Comparisons of latencies between macaques (112 ms) and humans (192 ms) suggested that the 3:5 ratio could be preserved in higher cognitive regions of face processing between those species.

Influence of negative mood on restrained eaters’ memory suppression of food cues: An event-related potentials study

Negative mood has been found to be a critical trigger for overeating in restrained eaters. The ability to suppress thinking of palatable food cues is crucial to control hedonic eating; nevertheless, little research has been conducted to explore inhibitory control in cognitive processes among restrained eaters. To address this gap, this study primed restrained eaters with negative (n = 23) or neutral emotions (n = 24) and applied a Think/No-think paradigm to explore their retrieval facilitation/suppression ability for food cues, while recording Electroencephalogram (EEG) data. Results indicated that the recall rate of the No-think condition (retrieval suppressing task) was higher than the Think condition (retrieval task). Negative affect did not influence the recall rate, but it did evoke smaller N2 amplitudes, larger P2 and P3 amplitudes, as well as late positive component (LPC) amplitudes. Among these components, P2 evoked by the No-think and Think conditions was larger than the perceptual control condition. Our findings suggested that in negative moods, restrained eaters need to allocate more attentional resources to suppress food cues. The findings further demonstrated that the influence of negative moods appeared at an early stage of cognitive processing and caused a resource depletion in memory suppression. This research provides a neurophysiological basis for understanding emotional influences on the process of restrained eaters’ inhibition control for external food cues.

The processing of intimately familiar and unfamiliar voices: Specific neural responses of speaker recognition and identification.

Research has repeatedly shown that familiar and unfamiliar voices elicit different neural responses. But it has also been suggested that different neural correlates associate with the feeling of having heard a voice and knowing who the voice represents. The terminology used to designate these varying responses remains vague, creating a degree of confusion in the literature. Additionally, terms serving to designate tasks of voice discrimination, voice recognition, and speaker identification are often inconsistent creating further ambiguities. The present study used event-related potentials (ERPs) to clarify the difference between responses to 1) unknown voices, 2) trained-to-familiar voices as speech stimuli are repeatedly presented, and 3) intimately familiar voices. In an experiment, 13 participants listened to repeated utterances recorded from 12 speakers. Only one of the 12 voices was intimately familiar to a participant, whereas the remaining 11 voices were unfamiliar. The frequency of presentation of these 11 unfamiliar voices varied with only one being frequently presented (the trained-to-familiar voice). ERP analyses revealed different responses for intimately familiar and unfamiliar voices in two distinct time windows (P2 between 200–250 ms and a late positive component, LPC, between 450–850 ms post-onset) with late responses occurring only for intimately familiar voices. The LPC present sustained shifts, and short-time ERP components appear to reflect an early recognition stage. The trained voice equally elicited distinct responses, compared to rarely heard voices, but these occurred in a third time window (N250 between 300–350 ms post-onset). Overall, the timing of responses suggests that the processing of intimately familiar voices operates in two distinct steps of voice recognition, marked by a P2 on right centro-frontal sites, and speaker identification marked by an LPC component. The recognition of frequently heard voices entails an independent recognition process marked by a differential N250. Based on the present results and previous observations, it is proposed that there is a need to distinguish between processes of voice “recognition” and “identification”. The present study also specifies test conditions serving to reveal this distinction in neural responses, one of which bears on the length of speech stimuli given the late responses associated with voice identification.

Dissociating Perceptual Awareness and Postperceptual Processing: The P300 Is Not a Reliable Marker of Somatosensory Target Detection.

A central challenge in the study of conscious perception lies in dissociating the neural correlates of perceptual awareness from those reflecting its precursors and consequences. No-report paradigms have been instrumental in this endeavor, demonstrating that the event-related potential P300, recorded from the human scalp, reflects reports rather than awareness. However, these paradigms cannot probe the degree to which stimuli are consciously processed from trial to trial and, thus, leave open the possibility that the P300 is a genuine correlate of conscious access enabling reports. Here, instead of removing report requirements, we took the opposite approach and equated postperceptual task demands across conscious and unconscious trials by orthogonalizing target detection and overt reports in a somatosensory detection task. We used Bayesian model selection to track the transformation from physical to perceptual processing stages in the EEG data of 24 male and female participants and show that the early P50 component scaled with physical stimulus intensity, whereas the N140 component was the first correlate of target detection. The late P300 component was elicited for both perceived and unperceived stimuli and was not substantially modulated by target detection. This was in stark contrast to a control experiment using a classical direct report task, which replicated the P50 and N140 effects but additionally showed a strong effect of target detection in the P300 time range. Our results demonstrate the task dependence of the P300 in the somatosensory modality and show that late cortical potentials dissociate from perceptual awareness even when stimuli are always reported.SIGNIFICANCE STATEMENT The time it takes for sensory information to enter our conscious experience can be an indicator of the neural processing stages that lead to perceptual awareness. However, because many cognitive processes routinely correlate with perception, isolating those signals that uniquely reflect perceptual awareness is not a trivial task. Here, we show that late electroencephalography signals cease to correlate with somatosensory awareness when common task confounds are controlled. Importantly, by balancing report requirements instead of abolishing them, we show that the lack of late effects cannot be explained by a lack of conscious access. Instead, we propose that conscious access occurs earlier, at ∼150 ms, supporting the view that early activity in sensory cortices is a neural correlate of conscious perception.

Abnormal ERPs and Brain Dynamics Mediate Basic Self Disturbance in Schizophrenia: A Review of EEG and MEG Studies.

Background: Interest in disordered sense of self in schizophrenia has recently re-emerged in the literature. It has been proposed that there is a basic self disturbance, underlying the diagnostic symptoms of schizophrenia, in which the person's sense of being a bounded individual continuous through time loses stability. This disturbance has been documented phenomenologically and at the level of cognitive tasks. However, the neural correlates of basic self disorder in schizophrenia are poorly understood.Methods: A search of PubMed was used to identify studies on self and schizophrenia that reported EEG or MEG data.Results: Thirty-three studies were identified, 32 using EEG and one using MEG. Their operationalizations of the self were divided into six paradigms: self-monitoring for errors, proprioception, self-other integration, self-referential processing, aberrant salience, and source monitoring. Participants with schizophrenia were less accurate on self-referential processing tasks and had slower response times across most studies. Event-related potential amplitudes differed across many early and late components, with reduced N100 suppression in source monitoring paradigms being the most replicated finding. Several studies found differences in one or more frequency band, but no coherent overall finding emerged in this area. Various other measures of brain dynamics also showed differences in single studies. Only some of the study designs were adequate to establish a causal relationship between the self and EEG or MEG measures.Conclusion: The broad range of changes suggests a global self disturbance at the neuronal level, possibly carried over from the resting state. Further studies that successfully isolate self-related effects are warranted to better understand the temporal-dynamic and spatial-topographic basis of self disorder and its relationship to basic self disturbance on the phenomenological level.

Electrophysiological and behavioral evaluation of auditory processing before and after speech therapy intervention in children after traumatic brain injury: Case reports

Objectives: to verify the effects of a speech therapy intervention program in children after moderate and severe traumatic brain injury using electrophysiological and behavioral assessment of central auditory processing. Method: Five children aged 9 to 11 years old who suffered closed brain trauma of moderate or severe degree for at least 6 months, right-handed, literate before the injury, diagnosed with Central Auditory Processing and Reading and Writing Disorders. Ten speech therapy intervention sessions were held, covering the area of language and auditory training activities. Children were submitted to electrophysiological evaluation with Long Latency Auditory Evoked Potential and behavioral assessment of central auditory processing, pre and post intervention. Results: Statistically significant, after speech therapy intervention, in the LLAEP with tone burst, there was an improvement in the latencies of the N2 component in both ears and P3 in the right ear. CAPD improves the memory test for verbal sounds in sequence and the speech test with white noise in the right ear. Conclusion: After the speech therapy intervention program in individuals with TBI it was observed: reduction of the latency of the N1 component in the left ear, in the LLAEP with tone burst; reduction of the latencies of the components N1, P2 and N2 in the right and left ears, and for the latency of the P3 only in the right ear, in the LLAEP with complex stimuli and performance improvement in the behavioral tests of central auditory memory processing for verbal sounds in sequence and speech with white noise.

Reduced early fearful face processing during perceptual distraction in high trait anxious participants

Fearful facial expressions are prioritized across different stages of information processing as reflected by early, mid-latency, and late components of event-related brain potentials (ERP). Trait anxiety has been proposed to modulate these responses, but it is yet unclear how such modulations depend on feature-based attention. In this preregistered study (N=80), we investigated the effects of trait anxiety on ERP differences between fearful and neutral faces across three different tasks. Participants had to discriminate either the orientation of lines overlaid onto the faces, the gender of the face, or the emotional expression, thus increasing attention to emotionally relevant facial features across the tasks. Fearful versus neutral faces elicited increased P1 and N170 amplitudes across tasks and potentiated amplitudes when attention was directed to faces (early posterior negativity [EPN]) or the expression (EPN and late positive potential). Higher trait anxiety was related to smaller EPN differences between fearful and neutral faces during the perceptual discrimination task. This early relationship suggests reduced instead of amplified processing of fearful faces for high trait anxious participants under perceptual distraction.

Electrophysiological correlates of the somatotopically organized tactile duration aftereffect

Adaptation to sensory events of long or short duration leads to a negative aftereffect, in which a new target event (of median duration) following the adaptation will be perceived to be shorter or longer than is actually the case. This illusion has been observed in visual, auditory, and tactile modalities. This study used event-related potentials (ERPs) to examine the tactile duration aftereffect, using the contingent negative variation (CNV) and the late positive component (LPC) as a way to characterize the temporal processes. The tactile duration adaptation was found to induce a significant aftereffect within a somatotopic framework. Moreover, the CNV in the contralateral scalp and the LPC in the fronto-central scalp were both modulated by the tactile duration adaptation. Specifically, adaptation to a short tactile duration increased the CNV and LPC amplitudes, whereas adaptation to a long tactile duration decreased them. This modulation was contingent on the topographic distance between fingers, which was only observed when the adapting and test fingers were consistent or adjacent, but not homologous. In sum, these results reveal a coherent behavioral-electrophysiological link in the somatotopically organized tactile duration aftereffect.

Reaching Out for Food: How Food Incentives Modulate Peripersonal Space Perception.

Two experiments were conducted to determine, first, whether food items influence participants’ estimations of the size of their subjective peripersonal space. It was of particular interest whether this representation is influenced by satiated/hungry states and is differentially affected by valence and calorie content of depicted stimuli. Second, event-related brain potentials (ERPs) were used, in order to obtain information about the time course of the observed effects and how they depend on the spatial location of the food pictures. For that purpose, participants had to decide whether food items shown at various distances along a horizontal plane in front of them, were reachable or not. In Experiment 1, when participants were hungry, they perceived an increase of their peripersonal space modulated by high-calorie items which were experienced as being more reachable than low-calorie items. In Experiment 2, the reachability findings were replicated and early and late components of ERPs showed an attentional enhancement in far space for food items when participants were hungry. These findings suggest that participants’ subjective peripersonal space increased while being hungry, especially for high-calorie contents. Attention also seems to be oriented more strongly to far space items due to their expected incentive-related salience, expanding the subjective representation of peripersonal space.

Increased Neural Efficiency in Visual Word Recognition: Evidence from Alterations in Event-Related Potentials and Multiscale Entropy.

Visual word recognition is a relatively effortless process, but recent research suggests the system involved is malleable, with evidence of increases in behavioural efficiency after prolonged lexical decision task (LDT) performance. However, the extent of neural changes has yet to be characterized in this context. The neural changes that occur could be related to a shift from initially effortful performance that is supported by control-related processing, to efficient task performance that is supported by domain-specific processing. To investigate this, we replicated the British Lexicon Project, and had participants complete 16 h of LDT over several days. We recorded electroencephalography (EEG) at three intervals to track neural change during LDT performance and assessed event-related potentials and brain signal complexity. We found that response times decreased during LDT performance, and there was evidence of neural change through N170, P200, N400, and late positive component (LPC) amplitudes across the EEG sessions, which suggested a shift from control-related to domain-specific processing. We also found widespread complexity decreases alongside localized increases, suggesting that processing became more efficient with specific increases in processing flexibility. Together, these findings suggest that neural processing becomes more efficient and optimized to support prolonged LDT performance.

Electrophysiological Study of Visual Pathways in Nevoid Basal Cell Carcinoma Syndrome Patients.

IntroductionGorlin-Goltz syndrome (GGS) also known as nevoid basal cell carcinoma syndrome (NBCCS) is a complex rare genetic disorder characterized by a wide range of clinical and radiological manifestations. Ophthalmological alterations have always been reported, but no study on the eventual pattern visual evoked potentials (pVEPs) abnormalities has yet been published.PurposeThe purpose of the study was to evaluate the functionality of the optic pathways in a group of NBCCS patients through pattern reversal VEPs, after a thorough exclusion of subjects with preexisting ocular and optic pathways pathologies.MethodsNineteen NBCCS patients (31 eyes) and 20 healthy controls (40 eyes) have been recruited for this study. All subjects underwent an evaluation of the functionality of the optic pathways through pVEPs with small (120ʹ), medium (60ʹ), and large (15ʹ) check size stimulation.ResultsNBCCS patients showed a statistically significant alteration in the transmission of the macular pathway function when compared to controls. PVEPs analysis confirmed a reduced amplitude and an increased latency of the P100 component, suggesting an involvement of the visual pathway even in the absence of ocular clinical manifestations.ConclusionVisual pathways may have been affected both by a subclinical myelination deficit, determined directly by the genetic alteration, as well as by neurological abnormalities typical of this syndrome. Further studies are warranted.