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1.
Dev Neuropsychol ; 49(3): 111-137, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38469855

RESUMO

This systematic review aimed to examine the possible implication of visual-perceptual, visuo-attentional and oculomotor processing in the reading deficits frequently experienced by children with Neurofibromatosis type 1 (NF1), as previously shown in dyslexia. Using PRISMA methodological guidelines, we examined 49 studies; most of these reported visual-processing deficits in this population, raising the importance of directly studying the visuo-perceptual and visuo-attentional processes and eye-movement control involved in the learning-to-read process in NF1. The discussion provides a reflection for a better understanding of how visual-processing skills interact with reading deficits in NF1, as well as new avenues for their screening and care.


Assuntos
Dislexia , Neurofibromatose 1 , Criança , Humanos , Leitura , Neurofibromatose 1/complicações , Neurofibromatose 1/epidemiologia , Dislexia/diagnóstico , Dislexia/etiologia , Percepção Visual , Aprendizagem
2.
Mater Horiz ; 11(8): 1934-1943, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38345761

RESUMO

The development of flexible synaptic devices with multicolor signal response is important to exploit advanced artificial visual perception systems. The Sn vacancy-dominant memory and narrow gap characteristics of PEA2SnI4 make it suitable as a functional layer in ultraviolet-visible (UV-Vis) light-stimulated synaptic devices. However, such device tends to have high dark current and poor sensitivity, which is not conducive to subsequent information processing. Here, we proposed a self-powered flexible optoelectronic synapse based on PEA2SnI4 films. By introducing the electron transport layer (ETL), the dark current of the device is decreased by 5 orders of magnitude as compared to the Au/PEA2SnI4/ITO device, and the sensitivity is increased from 10.3% to 99.2% at 1.25 mW cm-2 light illumination (520 nm), indicating the vital role of the introduced ETL in promoting the separation of excitons in the interface and inhibiting the free carrier transfer. On this basis, the optoelectronic synaptic functions with integrated sensing, recognition, and memory features were realized. The array device exhibits UV-Vis light sensitivity and tunable synaptic plasticity, enabling its application for multicolor visual sensing and skin sunburn warning. This work provides an effective strategy for fabricating multicolor intelligent sensors and artificial vision systems, which facilitate the practical application of artificial optoelectronic synapses.


Assuntos
Queimadura Solar , Queimadura Solar/prevenção & controle , Humanos , Raios Ultravioleta/efeitos adversos , Percepção Visual/fisiologia
3.
Pediatr Blood Cancer ; 71(5): e30910, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38342954

RESUMO

BACKGROUND: The contribution of tumor type, multimodal treatment, and other patient-related factors upon long-term cognitive sequelae in infant brain tumor survivors remains undefined. We add our retrospective analysis of neuropsychological and quality of survival (QoS) outcome data of survivors of atypical teratoid/rhabdoid tumors (ATRT) and extracranial malignant rhabdoid tumors of the soft tissues (eMRT) and kidneys (RTK) treated within the same framework. Neuropsychological data from children with ATRT were compared to data from children with non-irradiated low-grade glioma (LGG). PATIENTS AND METHODS: Following surgery, patients (0-36 months at diagnosis) had received radio-chemotherapy (up to 54 Gy; ATRT: n = 13; eMRT/RTK: n = 7), chemotherapy only (LGG: n = 4; eMRT/RTK: n = 1) or had been observed (LGG: n = 11). Neuropsychological evaluation employing comparable tests was performed at median 6.8 years (ATRT), 6.6 years (eMRT/RTK), and 5.2 years (LGG) post diagnosis. RESULTS: We detected sequelae in various domains for all tumor types. Group comparison showed impairments, specifically in fluid intelligence (p = .041; d = 1.11) and visual processing (p = .001; d = 2.09) in ATRT patients when compared to LGG patients. Results for psychomotor speed and attention abilities were significantly below the norm for both groups (p < .001-.019; d = 0.79-1.90). Diagnosis predicted impairments of cognitive outcome, while sex- and age-related variables did not. QoS outcome for all rhabdoid patients displayed impairments mainly in social (p = .008; d = 0.74) and school functioning (p = .048; d = 0.67), as well as lower overall scores in psychosocial functioning (p = .023; d = 0.78) and quality of life (p = .006; d = 0.79) compared to healthy controls. CONCLUSION: Survivors of infant ATRT experience various late effects in cognition and QoS following multimodal treatment, while infant LGG patients without radiotherapy demonstrated comparable impairments in psychomotor and attention abilities. Early onset and multimodal treatment of rhabdoid tumors require close monitoring of neuropsychological and QoS sequelae.


Assuntos
Neoplasias Encefálicas , Neoplasias do Sistema Nervoso Central , Glioma , Neoplasias Neuroepiteliomatosas , Tumor Rabdoide , Teratoma , Criança , Lactente , Humanos , Tumor Rabdoide/complicações , Tumor Rabdoide/terapia , Estudos Retrospectivos , Qualidade de Vida , Teratoma/complicações , Teratoma/terapia , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/terapia , Neoplasias do Sistema Nervoso Central/patologia , Progressão da Doença , Percepção Visual , Cognição , Sobreviventes
4.
Cogn Affect Behav Neurosci ; 24(2): 351-367, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38253774

RESUMO

The rapid serial visual presentation (RSVP) task and continuous performance tasks (CPT) are used to assess attentional impairments in patients with psychiatric and neurological conditions. This study developed a novel touchscreen task for rats based on the structure of a human RSVP task and used pharmacological manipulations to investigate their effects on different performance measures. Normal animals were trained to respond to a target image and withhold responding to distractor images presented within a continuous sequence. In a second version of the task, a false-alarm image was included, so performance could be assessed relative to two types of nontarget distractors. The effects of acute administration of stimulant and nonstimulant treatments for ADHD (amphetamine and atomoxetine) were tested in both tasks. Methylphenidate, ketamine, and nicotine were tested in the first task only. Amphetamine made animals more impulsive and decreased overall accuracy but increased accuracy when the target was presented early in the image sequence. Atomoxetine improved accuracy overall with a specific reduction in false-alarm responses and a shift in the attentional curve reflecting improved accuracy for targets later in the image sequence. However, atomoxetine also slowed responding and increased omissions. Ketamine, nicotine, and methylphenidate had no specific effects at the doses tested. These results suggest that stimulant versus nonstimulant treatments have different effects on attention and impulsive behaviour in this rat version of an RSVP task. These results also suggest that RSVP-like tasks have the potential to be used to study attention in rodents.


Assuntos
Anfetamina , Cloridrato de Atomoxetina , Atenção , Estimulantes do Sistema Nervoso Central , Ketamina , Metilfenidato , Nicotina , Animais , Estimulantes do Sistema Nervoso Central/farmacologia , Estimulantes do Sistema Nervoso Central/administração & dosagem , Cloridrato de Atomoxetina/farmacologia , Cloridrato de Atomoxetina/administração & dosagem , Atenção/efeitos dos fármacos , Atenção/fisiologia , Masculino , Ratos , Metilfenidato/farmacologia , Metilfenidato/administração & dosagem , Nicotina/farmacologia , Nicotina/administração & dosagem , Anfetamina/farmacologia , Anfetamina/administração & dosagem , Ketamina/farmacologia , Ketamina/administração & dosagem , Estimulação Luminosa/métodos , Inibidores da Captação Adrenérgica/farmacologia , Inibidores da Captação Adrenérgica/administração & dosagem , Aprendizagem Seriada/efeitos dos fármacos , Aprendizagem Seriada/fisiologia , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/fisiologia , Percepção Visual/efeitos dos fármacos , Percepção Visual/fisiologia , Ratos Sprague-Dawley
5.
Laryngoscope ; 134(6): 2726-2733, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38214383

RESUMO

OBJECTIVE: The purpose of this study is to determine children's perception of secondary cleft lip deformity (SCLD) using objective eye tracking technology and subjective responses on a survey to understand pediatric perceptions of facial scarring. DESIGN: Cross-sectional study of participants aged 5-17 years old. METHODS: Participants viewed images of children's faces with an eye tracking device. Sixteen images were displayed, 12 with unilateral SCLD and four with no facial scarring. Eye tracking data were obtained. Gaze samples were analyzed for areas of interest (AOIs). Immediately after viewing each image, participants answered two survey questions relating to facial asymmetry attitude toward the child pictured. For analysis, participants were divided into age groups. RESULTS: A total of 259 participants were enrolled (42.5% female). Mean age was 10.5 years and 78% identified as White. In all age groups, total fixation time was greater for SCLD compared to control images. Early elementary age children spent significantly less time assessing the nose AOI compared to other groups, and also spent the least total fixation time and had the lowest visit count on all AOIs. Subjective survey questions showed similar trends with elementary age not noticing facial asymmetry compared to older age groups. CONCLUSION: This study demonstrates the successful use of eye tracking technology in children as young as 5 years old. This study suggests that SCLD is perceived as less noticeable in elementary age children and becomes more noticeable to older groups. Understanding peer perception on SCLD from this study may impact decision on revision surgery for SCLD. LEVEL OF EVIDENCE: IV Laryngoscope, 134:2726-2733, 2024.


Assuntos
Cicatriz , Fenda Labial , Tecnologia de Rastreamento Ocular , Humanos , Feminino , Fenda Labial/cirurgia , Fenda Labial/psicologia , Fenda Labial/fisiopatologia , Criança , Masculino , Estudos Transversais , Adolescente , Pré-Escolar , Cicatriz/psicologia , Cicatriz/etiologia , Percepção Visual/fisiologia , Inquéritos e Questionários , Assimetria Facial/psicologia
6.
J Reconstr Microsurg ; 40(1): 30-39, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36928906

RESUMO

BACKGROUND: Microsurgical reconstruction for bilateral mastectomy defects after unilateral radiation often results in asymmetry, despite both flap tissues never being radiated. METHODS: Photos of 16 patients who received prior radiation to one breast and underwent bilateral abdominal free flap reconstruction were taken postoperatively. Layperson and expert assessment were attained via online crowdsourcing and a panel of attending surgeons and senior residents. Stratification by interflap weight differences was done for subanalysis. RESULTS: A total of 399 laypersons responded, with the majority (57.3%) reporting that the radiated breast appeared smaller than the nonradiated breast. When the photos were stratified by interflap weight differences, the photos with the radiated side flap weight over 3% more than nonradiated side were significantly more likely to be perceived by laypersons as the same size (odds ratio [OR] = 2.7; p < 0.001) and of similar aesthetic (OR = 1.9; p < 0.001) when compared with photos with same-sized flaps. Of the expert responses (n = 16), the radiated side was perceived as smaller 72.3% of the time and the nonradiated side appeared more aesthetic 52.7% of the time. Contrary to layperson responses, the experts tend to report the radiated side as smaller despite varying flap weight. Interestingly, expert raters were significantly more likely to rate the flaps of equal aesthetics when the radiated side has a flap larger by 3% or more (OR = 3.6; p < 0.001). CONCLUSION: Higher aesthetic scores were noted when larger flaps were inset to the radiated envelope by both laypersons and experts, suggesting potential technical refinement in reconstructive outcomes.


Assuntos
Neoplasias da Mama , Retalhos de Tecido Biológico , Mamoplastia , Humanos , Feminino , Mastectomia/métodos , Mamoplastia/métodos , Estudos Retrospectivos , Percepção Visual
8.
J Neuropsychol ; 18 Suppl 1: 115-133, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37391874

RESUMO

Patients with anterior temporal lobe (ATL) resection due to mesial temporal lobe epilepsy (MTLE) have difficulties at identifying familiar faces and explicitly remembering newly learned faces but their ability to individuate unfamiliar faces remains largely unknown. Moreover, the extent to which their difficulties with familiar face identity recognition and learning is truly due to the ATL resection remains unknown. Here, we report a study of 24 MTLE patients and matched healthy controls tested with an extensive set of seven face and visual object recognition tasks (including three tasks evaluating unfamiliar face individuation) before and about 6 months after unilateral (nine left, 15 right) ATL resection. We found that ATL resection has little or no effect on the patients' preserved pre-surgical ability to perform unfamiliar face individuation, both at the group and individual levels. More surprisingly, ATL resection also has little effect on the patients' performance at recognizing and naming famous faces as well as at learning new faces. A substantial proportion of right MTLE patients (33%) even improved their response times on several tasks, which may indicate a functional release of visuo-spatial processing after resection in the right ATL. Altogether this study shows that face recognition abilities are mainly unaffected by ATL resection in MTLE, either because the critical regions for face recognition are spared or because performance at some tasks is already lower than normal preoperatively. Overall, these findings urge caution when interpreting the causal effect of brain lesions on face recognition ability in patients with ATL resection due to MTLE. They also illustrate the complexity of predicting cognitive outcomes after epilepsy surgery because of the influence of many different intertwined factors.


Assuntos
Epilepsia do Lobo Temporal , Reconhecimento Facial , Humanos , Lobectomia Temporal Anterior/efeitos adversos , Epilepsia do Lobo Temporal/cirurgia , Lobo Temporal/patologia , Percepção Visual , Testes Neuropsicológicos
9.
Neurol Sci ; 45(5): 1849-1860, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38157102

RESUMO

INTRODUCTION: Visual attention is a cognitive skill related to visual perception and neural activity, and also moderated by expertise, in time-constrained professional domains (e.g., aviation, driving, sport, surgery). However, the contribution of both perceptual and neural processes on performance has been studied separately in the literature. DEVELOPMENT: We defend an integration of visual and neural signals to offer a more complete picture of the visual attention displayed by professionals of different skill levels when performing free-viewing tasks. Specifically, we propose to zoom the analysis in data related to the quiet eye and P300 component jointly, as a novel signal processing approach to evaluate professionals' visual attention. CONCLUSION: This review highlights the advantages of using portable eye trackers and electroencephalogram systems altogether, as a promising technique for a better understanding of early cognitive components related to attentional processes. Altogether, the eye-fixation-related potentials method may provide a better understanding of the cognitive mechanisms employed by the participants in natural settings, revealing what visual information is of interest for participants and distinguishing the neural bases of visual attention between targets and non-targets whenever they perceive a stimulus during free viewing experiments.


Assuntos
Esportes , Percepção Visual , Humanos , Percepção Visual/fisiologia , Fixação Ocular , Eletroencefalografia , Potenciais Evocados P300
10.
J Neural Eng ; 20(6)2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-38118169

RESUMO

Objective. Currently, few non-invasive measures exist for directly measuring spinal sensorimotor networks. Electrospinography (ESG) is one non-invasive method but is primarily used to measure evoked responses or for monitoring the spinal cord during surgery. Our objectives were to evaluate the feasibility of ESG to measure spinal sensorimotor networks by determining spatiotemporal and functional connectivity changes during single-joint movements at the spinal and cortical levels.Approach. We synchronously recorded electroencephalography (EEG), electromyography, and ESG in ten neurologically intact adults while performing one of three lower-limb tasks (no movement, plantar-flexion and knee flexion) in the prone position. A multi-pronged approach was applied for removing artifacts usingH∞filtering, artifact subspace reconstruction and independent component (IC) analysis. Next, data were segmented by task and ICs of EEG were clustered across participants. Within-participant analysis of ICs and ESG data was conducted, and ESG was characterized in the time and frequency domains. Generalized partial directed coherence analysis was performed within ICs and between ICs and ESG data by participant and task.Results.K-means clustering resulted in five clusters of ICs at Brodmann areas (BAs) 9, BA 8, BA 39, BA 4, and BA 22. Areas associated with motor planning, working memory, visual processing, movement, and attention, respectively. Time-frequency analysis of ESG data found localized changes during movement execution when compared to no movement. Lastly, we found bi-directional changes in functional connectivity (p < 0.05, adjusted for multiple comparisons) within IC's and between IC's and ESG sensors during movement when compared to the no movement condition.Significance. To our knowledge this is the first report using high density ESG for characterizing single joint lower limb movements. Our findings provide support that ESG contains information about efferent and afferent signaling in neurologically intact adults and suggests that we can utilize ESG to directly study the spinal cord.


Assuntos
Eletroencefalografia , Medula Espinal , Adulto , Humanos , Eletroencefalografia/métodos , Movimento/fisiologia , Percepção Visual , Memória de Curto Prazo
11.
Orphanet J Rare Dis ; 18(1): 389, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38087330

RESUMO

BACKGROUND: Cystinosis, a rare lysosomal storage disease caused by mutations in the CTNS gene, is characterized by cystine crystallization and accumulation within multiple tissues, including kidney and brain. Its impact on neural function appears mild relative to its effects on other organs during early disease, but since therapeutic advances have led to substantially increased life expectancy, neurological implications are of increasing interest, necessitating deeper understanding of the impact of cystinosis on neurocognitive function. Behavioral difficulties have been reported in cystinosis in the visual domain. Very little is known, however, about how the brains of people living with cystinosis process visual information. This is especially interesting given that cystine accumulation in the cornea and posterior ocular structures is a hallmark of cystinosis. METHODS: Here, high-density scalp electrophysiology was recorded to visual stimuli (during a Go/No-Go task) to investigate visual processing in individuals with cystinosis, compared to age-matched controls. Analyses focused on early stages of cortical visual processing. RESULTS: The groups differed in their initial cortical response, with individuals with cystinosis exhibiting a significantly larger visual evoked potential (VEP) in the 130-150 ms time window. The groups also differed in the associations between neural responses and verbal abilities: While controls with higher IQ scores presented larger neural responses, that relationship was not observed in cystinosis. CONCLUSIONS: The enlarged VEP in cystinosis could be the result of cortical hyperexcitability and/or differences in attentional engagement and explain, at least partially, the visual and visual-spatial difficulties described in this population.


Assuntos
Sistemas de Transporte de Aminoácidos Neutros , Cistinose , Oftalmopatias , Criança , Adulto , Humanos , Cistinose/genética , Cistinose/tratamento farmacológico , Cistina/genética , Cistina/metabolismo , Cistina/uso terapêutico , Potenciais Evocados Visuais , Mutação/genética , Percepção Visual , Sistemas de Transporte de Aminoácidos Neutros/genética , Sistemas de Transporte de Aminoácidos Neutros/uso terapêutico
12.
Acta neurol. colomb ; 39(4)dic. 2023.
Artigo em Espanhol | LILACS | ID: biblio-1533512

RESUMO

Introducción: La alucinosis peduncular (AP) hace referencia a alucinaciones autodiscriminadas, cuyo origen son lesiones en el mesencéfalo y en el puente. Presentación del caso: Paciente 27 años, femenina, con alucinaciones visuales, auditivas autodiscriminadas por ella misma, sin antecedentes previos de importancia y con lesiones en resonancia magnética cerebral y cervical en el pedúnculo cerebeloso superior, tegmento pontino, y en columna cervical con bandas oligoclonales patrón 2, que cumplían criterios de Mc Donalds para esclerosis múltiple. Discusión: La alucinosis peduncular hace referencia a la presencia de alucinaciones visuales, criticadas por el paciente, con la consecuencia de lesiones de las vías inhibitorias por deaferentación y desinhibición mesencéfalotalámicas, y retinogenículo calcarina, descritas como manifestación de múltiples patologías neurológicas como trauma, afectación vascular, tumores y pocos casos de enfermedad desmielinizante, entre otras. Conclusión: La alucinosis peduncular es una forma atípica de presentación de lesiones pontomesencefálicas descritas en varias patologías; se debe tener en cuenta en la localización de la lesión neurológica; se han reportado pocos casos como síntoma de la enfermedad desmielinizante.


Introduction: Peduncular hallucinosis (PA) refers to self-discriminating hallucinations, these are caused by lesions in the midbrain and pons. Presentation of the case: 27-year-old right handed female patient with visual and auditory hallucinations self-discriminated by the patient, with no prior history of importance and with lesions in cerebral and cervical Magnetic Resonance in the superior cerebellar peduncle, pontine tegmentum, and in the cervical spine with pattern 2 oligo clonal bands, which met Mc Donald's criteria for multiple sclerosis. Discussion: Peduncular hallucinosis refers to the presence of visual hallucinations criticized by the patient, consequence of lesions in the inhibitory pathways with deafferentation and disinhibition of the midbrain-thalamic and retinogeniculus-calcarine pathways. Described as a manifestation of multiple neurological pathologies such as trauma, vascular, tumor and few cases of demyelinating among others. Conclusion: Peduncular hallucinosis is an atypical form of presentation of pontomesencephalic lesions described in several pathologies, it must be taken into account when locating the neurological lesion, few cases have been reported as symptom of the demyelinating disease.


Assuntos
Doenças Desmielinizantes , Diencéfalo , Esclerose Múltipla , Percepção Visual , Tronco Encefálico
13.
Cell Rep ; 42(9): 113133, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37708021

RESUMO

Visual stimuli that deviate from the current context elicit augmented responses in the primary visual cortex (V1). These heightened responses, known as "deviance detection," require local inhibition in the V1 and top-down input from the anterior cingulate area (ACa). Here, we investigated the mechanisms by which the ACa and V1 interact to support deviance detection. Local field potential recordings in mice during an oddball paradigm showed that ACa-V1 synchrony peaks in the theta/alpha band (≈10 Hz). Two-photon imaging in the V1 revealed that mainly pyramidal neurons exhibited deviance detection, while contextually redundant stimuli increased vasoactive intestinal peptide (VIP)-positive interneuron (VIP) activity and decreased somatostatin-positive interneuron (SST) activity. Optogenetic drive of ACa-V1 inputs at 10 Hz activated V1-VIPs but inhibited V1-SSTs, mirroring the dynamics present during the oddball paradigm. Chemogenetic inhibition of V1-VIPs disrupted Aca-V1 synchrony and deviance detection in the V1. These results outline temporal and interneuron-specific mechanisms of top-down modulation that support visual context processing.


Assuntos
Córtex Cerebral , Percepção Visual , Animais , Camundongos , Percepção Visual/fisiologia , Córtex Cerebral/metabolismo , Células Piramidais/metabolismo , Interneurônios/metabolismo , Optogenética , Peptídeo Intestinal Vasoativo/metabolismo
14.
J Vestib Res ; 33(6): 403-409, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37574747

RESUMO

BACKGROUND: Cochlear implantation (CI) is associated with changes in the histopathology of the inner ear and impairment of vestibular function. OBJECTIVE: The objectives of our study were to evaluate patients for clinical manifestations of space perception and balance changes before surgery, compare them with asymptomatic subjects (controls), and report changes in posturography and subjective visual vertical (SVV) during the acute post-surgery period in patients. METHODS: Examination was performed using static posturography and the SVV measurement. We examined 46 control subjects and 39 CI patients. Patients were examined pre-surgery (Pre), 2nd day (D2) and then 14th day (D14) after implantation. RESULTS: Baseline SVV was not different between patients and control group. There was a statistically significant difference (p < 0.001) in SVV between subgroups of right- and left-implanted patients at D2 (-1.36±3.02° and 2.71±2.36°, right and left side implanted respectively) but not Pre (0.76±1.07° and 0.31±1.82°) or D14 (0.72±1.83° and 1.29±1.60°). Baseline posturography parameters between patients and control group were statistically significantly different during stance on foam with eyes closed (p < 0.05). There was no statistically significant difference in posturography among Pre, D2 and D14. CONCLUSIONS: CI candidates have impaired postural control before surgery. CI surgery influences perception of subjective visual vertical in acute post-surgery period with SVV deviation contralateral to side of cochlear implantation, but not after two weeks.


Assuntos
Implante Coclear , Vestíbulo do Labirinto , Humanos , Percepção Espacial , Equilíbrio Postural , Percepção Visual
15.
Behav Brain Funct ; 19(1): 13, 2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37620941

RESUMO

BACKGROUND: Cross-frequency phase-amplitude coupling (PAC) of cortical oscillations is observed within and across cortical regions during higher-order cognitive processes. Particularly, the PAC of alpha and gamma waves in the occipital cortex is closely associated with visual perception. In theory, gamma oscillation is a neuronal representation of visual stimuli, which drives the duty cycle of visual perception together with alpha oscillation. Therefore, it is believed that the timing of entrainment in alpha-gamma PAC may play a critical role in the performance of visual perception. We hypothesized that transcranial alternating current stimulation (tACS) with gamma waves entrained at the troughs of alpha waves would enhance the dynamic visual acuity (DVA). METHOD: We attempted to modulate the performance of DVA by using tACS. The waveforms of the tACS were tailored to target PAC over the occipital cortex. The waveforms contained gamma (80 Hz) waves oscillating at either the peaks or troughs of alpha (10 Hz) waves. Participants performed computerized DVA task before, immediately after, and 10 min after each stimulation sessions. EEG and EOG were recorded during the DVA task to assess inter-trial phase coherence (ITPC), the alpha-gamma PAC at occipital site and the eye movements. RESULTS: tACS with gamma waves entrained at alpha troughs effectively enhanced DVA, while the tACS with gamma waves entrained at alpha peaks did not affect DVA performance. Importantly, analyses of EEG and EOG showed that the enhancement of DVA performance originated solely from the neuromodulatory effects, and was not related to the modulation of saccadic eye movements. Consequently, DVA, one of the higher-order cognitive abilities, was successfully modulated using tACS with a tailored waveform. CONCLUSIONS: Our experimental results demonstrated that DVA performances were enhanced when tACS with gamma bursts entrained on alpha wave troughs were applied over the occipital cortex. Our findings suggest that using tACS with tailored waveforms, modulation of complex neuronal features could effectively enhance higher-order cognitive abilities such as DVA, which has never been modulated with conventional noninvasive brain stimulation methods.


Assuntos
Procedimentos Cirúrgicos Refrativos , Estimulação Transcraniana por Corrente Contínua , Humanos , Acuidade Visual , Percepção Visual , Movimentos Oculares
16.
Invest Ophthalmol Vis Sci ; 64(11): 5, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37535007

RESUMO

Purpose: To measure visual crowding, an essential bottleneck on object recognition and reliable psychophysical index of cortex organization, in older children and adults with horizontal concomitant strabismus before and after strabismus surgery. Methods: Using real-time eye tracking to ensure gaze-contingent display, we examined the peripheral visual crowding effects in older children and adults with horizontal concomitant strabismus but without amblyopia before and after strabismus surgery. Patients were asked to discriminate the orientation of the central tumbling E target letter with flankers arranged along the radial or tangential axis in the nasal or temporal hemifield at different eccentricities (5° or 10°). The critical spacing value, which is the minimum space between the target and the flankers required for correct discrimination, was obtained for comparisons before and after strabismus surgery. Results: Twelve individuals with exotropia (6 males, 21.75 ± 7.29 years, mean ± SD) and 15 individuals with esotropia (6 males, 24.13 ± 5.96 years) participated in this study. We found that strabismic individuals showed significantly larger critical spacing with nasotemporal asymmetry along the radial axis that related to the strabismus pattern, with exotropes exhibiting stronger temporal field crowding and esotropes exhibiting stronger nasal field crowding before surgical alignment. After surgery, the critical spacing was reduced and rebalanced between the nasal and temporal hemifields. Furthermore, the postoperative recovery of stereopsis was associated with the extent of nasotemporal balance of critical spacing. Conclusions: We find that optical realignment (i.e., strabismus surgery) can normalize the enlarged visual crowding effects, a reliable psychophysical index of cortical organization, in the peripheral visual field of older children and adults with strabismus and rebalance the nasotemporal asymmetry of crowding, promoting the recovery of postoperative stereopsis. Our results indicated a potential of experience-dependent cortical organization after axial alignment even for individuals who are out of the critical period of visual development, illuminating the capacity and limitations of optics on sensory plasticity and emphasizing the importance of ocular correction for clinical practice.


Assuntos
Ambliopia , Esotropia , Estrabismo , Adulto , Masculino , Criança , Humanos , Adolescente , Acuidade Visual , Estrabismo/cirurgia , Percepção Visual , Sulfadiazina
17.
Nervenarzt ; 94(8): 744-756, 2023 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-37535111

RESUMO

Neglect occurring after stroke, neoplasms or degenerative processes can lead to considerable disability in everyday life as can other disorders of spatial orientation. Therefore, a dedicated examination and early diagnostic classification are obligatory. Behavioral tests are helpful in this respect, enabling the clinician to obtain an initial overview of the existing deficits even at the patient's bedside. The clinical (bedside) examination of spatial neglect as well as the corresponding differential diagnostic procedure for the clarification of (possibly additionally or exclusively existing) hemianopia and extinction, as well as the examination of disorders of visuospatial perception, visuoconstructive disorders, topographic disorders, Bálint's syndrome, simultanagnosia, and optic ataxia are presented. The presentation is based on the newly revised (year 2023) guidelines of the Association of the Scientific Medical Societies in Germany (AWMF) on this subject area.


Assuntos
Apraxias , Transtornos da Percepção , Acidente Vascular Cerebral , Humanos , Percepção Visual , Cognição , Transtornos da Percepção/diagnóstico , Acidente Vascular Cerebral/diagnóstico
18.
Hippocampus ; 33(10): 1113-1122, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37483092

RESUMO

The prevailing view in human cognitive neuroscience associates the medial temporal lobes (MTLs) with declarative memory. Compelling experimental evidence has, however, demonstrated that these regions are specialized according to the representations processed, irrespective of the cognitive domain assessed. This account was supported by the study of patients with bilateral medial temporal amnesia, who exhibit impairments in perceptual tasks involving complex visual stimuli. Yet, little is known regarding the impact of unilateral MTL damage on complex visual abilities. To address this issue, we administered a visual matching task to 20 patients who underwent left (N = 12) or right (N = 8) anterior temporal lobectomy for drug-resistant epilepsy and to 38 healthy controls. Presentation viewpoint was manipulated to increase feature ambiguity, as this is critical to reveal impairments in perceptual tasks. Similar to control participants, patients with left-sided damage succeeded in all task conditions. In contrast, patients with right-sided damage had decreased accuracy compared with that of the other two groups, as well as increased response time. Notably, the accuracy of those with right-sided damage did not exceed chance level when feature ambiguity was high (i.e., when stimuli were presented from different viewpoints) for the most complex classes of stimuli (i.e., scenes and buildings, compared with single objects). The pattern reported in bilateral patients in previous studies was therefore reproduced in patients with right, but not left, resection. These results suggest that the complex visual-representation functions supported by the MTL are right-lateralized, and raise the question as to how the representational account of these regions applies to representations supported by left MTL regions.


Assuntos
Lobectomia Temporal Anterior , Epilepsia do Lobo Temporal , Humanos , Percepção Visual/fisiologia , Lobo Temporal/cirurgia , Lobo Temporal/fisiologia , Amnésia , Tempo de Reação , Imageamento por Ressonância Magnética , Epilepsia do Lobo Temporal/cirurgia , Testes Neuropsicológicos
19.
PLoS One ; 18(6): e0283376, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37289785

RESUMO

Diagnosing orthopantomograms (OPTs: panoramic radiographs) is an essential skill dentistry students acquire during university training. While prior research described experts' visual search behavior in radiology as global-to-focal for chest radiographs and mammography, generalizability to a hybrid search task in OPTs (i.e., searching for multiple, diverse anomalies) remains unclear. Addressing this gap, this study investigated visual search of N = 107 dentistry students while they were diagnosing anomalies in OPTs. Following a global-to-focal expert model, we hypothesized that students would use many, short fixations representing global search in earlier stages, and few, long fixations representing focal search in later stages. Furthermore, pupil dilation and mean fixation duration served as cognitive load measures. We hypothesized that later stages would be characterized by elaboration and a reflective search strategy, leading to higher cognitive load being associated with higher diagnostic performance in late compared to earlier stages. In line with the first hypothesis, students' visual search comprised of a three-stage process that grew increasingly focal in terms of the number of fixations and anomalies fixated. Contrary to the second hypothesis, mean fixation duration during anomaly fixations was positively associated with diagnostic performance across all stages. As OPTs greatly varied in how difficult it was to identify the anomalies contained therein, OPTs with above-average difficulty were sampled for exploratory analysis. Pupil dilation predicted diagnostic performance for difficult OPTs, possibly capturing elaborative cognitive processes and cognitive load compared to mean fixation duration. A visual analysis of fine-grained time slices indicated large cognitive load differences towards the end of trials, showcasing a richness-resolution-trade-off in data sampling crucial for future studies using time-slicing of eye tracking data.


Assuntos
Pupila , Percepção Visual , Humanos , Radiografia , Radiografia Panorâmica , Estudantes
20.
Surg Endosc ; 37(9): 6901-6907, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37316677

RESUMO

BACKGROUND: Gaming is a growing industry, having met an exponential growth amid the pandemic context. Video games improve the allocation and speed of attention and provide better spatial orientation in visual processing. These same qualities are sought after in GI endoscopists. This study aimed to investigate whether individuals with a gaming history have superior fine motor and visual skills on a virtual reality (VR) endoscopy simulator and if gaming consoles could be added as a proficiency tool in acquiring endoscopic skills. METHODS: Firstly, subjects' baseline psychomotor skills and hand-eye coordination were tested using a VR simulator. Secondly, subjects were assigned to either group C and asked to refrain from any gaming for 14 days, or group T, who were asked to play on a console for 14 days. All subjects were then retested. RESULTS: 81 students were included in the study. Baseline VR simulator testing showed better scores in those with a higher number of previous gaming hours (0 h-1598, 0 to 30 h-1970, 30 to 50 h-2150, 50 to 100 h-2395, > 100 h-2519; p < 0.05), with males outperforming females (p < 0.01). After spending an average of 19 h gaming, all parameters showed noteworthy improvement for those in group T (p < 0.01). No improvement was seen in group C. CONCLUSIONS: Subjects who engage in console gaming have superior psychomotor skills and perform better on VR simulators. Approximately 20 h of console gaming can improve one's simulator skills. With consoles being accessible, entertaining, and cheap, they could be used as an additional training platform for GI endoscopy residents.


Assuntos
Jogos de Vídeo , Realidade Virtual , Masculino , Feminino , Humanos , Competência Clínica , Percepção Visual , Endoscopia Gastrointestinal , Interface Usuário-Computador , Simulação por Computador
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