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1.
Stud Health Technol Inform ; 315: 661-662, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39049370

RESUMO

The aim of this study was to assess nurses' awareness and use of ChatGPT. The study was conducted in October 2023 with an online questionnaire for 124 nurses in the nursing education programme at West China Hospital. The questionnaire included participants' demographic information, awareness of ChatGPT, and actual experience of using it. A total of 57.3% (71/124) of the nurses completed the survey. Of these, 56.3% (40/71) were aware of ChatGPT and 43.7% (31/71) were not aware of ChatGPT. In terms of use, of the 20 who used ChatGPT, 13 used it for studying, 10 for essay writing, five for research and two for chatting. This study highlights the potential of ChatGPT to improve nurses' professional competence and effectiveness. Further research will focus on how ChatGPT can be used more effectively to support nurses' professional development and growth.


Assuntos
Atitude do Pessoal de Saúde , Inquéritos e Questionários , China , Humanos , Recursos Humanos de Enfermagem Hospitalar , Feminino , Adulto , Masculino
2.
Adv Mater ; : e2404696, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38923035

RESUMO

Soft robots adapt to complex environments for autonomous locomotion, manipulation, and perception are attractive for robot-environment interactions. Strategies to reconcile environment-triggered actuation and self-powered sensing responses to different stimuli remain challenging. By tuning the in situ vapor phase solvent exchange effect in continuous electrospinning, an asymmetric highly-aligned all-fiber membrane (HAFM) with a hierarchical "grape-like" nanosphere-assembled microfiber structure (specific surface area of 13.6 m2 g-1) and excellent mechanical toughness (tensile stress of 5.5 MPa, and fracture toughness of 798 KJ m-3) is developed, which shows efficient asymmetric actuation to both photothermal and humidity stimuli. The HAFM consists of a metal-organic framework (MOF)-enhanced moisture-responsive layer and an MXene-improved photothermal-responsive layer, which achieves substantial actuation with a bending curvature up to ≈7.23 cm-1 and a fast response of 0.60 cm-1 s-1. By tailoring the fiber alignment and bi-layer thickness ratio, different types of micromanipulators, automatic walking robots, and plant robots with programmable structures are demonstrated, which are realized for self-powered information perception of material type, object moisture, and temperature by integrating the autonomous triboelectric effect induced by photothermal-moisture actuation. This work presents fiber materials with programable hierarchical asymmetries and inspires a common strategy for self-powered organism-interface robots to interact with complex environments.

3.
Food Chem ; 448: 139118, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38552459

RESUMO

Carbonyl compounds are vital constituents that contribute to the flavor profile of alcoholic beverages. We examined 3-nitrophenylhydrazine as a derivatizing reagent for the measurement of 34 carbonyl compounds using UPLC-MS/MS. Adding formic acid and sodium acetate to the mobile phase significantly enhanced the detection limit of carbonyl compounds. The technique exhibited a notable extraction efficiency, yielding recovery percentages ranging from 83.6% to 117.1%, coupled with exceptional sensitivity, as evidenced by detection limits spanning from 0.07 µg/L to 4.80 µg/L. The relative standard deviation was <6.9%, indicating the precision and reliability of the analytical methodology. The method was verified by analyzing carbonyl compounds from red-fleshed kiwifruit wine. Furthermore, sensory assessment revealed that the amalgamation of tartaric acid, malic acid, and citric acid contributes to sour taste perception at sub-threshold concentrations through an additive interaction with supra-threshold non-volatile organic acids such as lactic acid and acetic acid.

4.
Healthcare (Basel) ; 12(3)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38338200

RESUMO

With the increased focus on patient-centered care, consensus on healthcare outcomes of importance to patients becomes crucial. Based on a systematic review of the literature, this study confirms the perspectives of patients on healthcare quality in GCC countries. Online databases were searched for relevant peer-reviewed articles published from 2012 to 2023. Twenty-two articles retrieved from the search were qualitatively analyzed based on the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Most articles (90%) reported studies conducted in Saudi Arabia. Patients in GCC countries face common problems in the care delivery process, which contribute to negative perceptions of quality. These problems include diagnostic and medication errors, provider-patient communication problems, missed appointments with physicians, problems in emergency care access due to geographical distance and transportation barriers, long waiting times, and physical environments. Notably, healthcare quality is perceived to be an outcome of multiple factors dependent on the location and category of healthcare service providers; for instance, disparities in perceptions of quality were observed between patients attending Primary Health Care (PHC) centers in rural and urban areas. Issues such as lack of equitable healthcare delivery and deficiencies in Emergency Medical Services (EMS) effectiveness were disparately recognized as quality concerns by different patient populations. The findings provide insights into healthcare quality and area of weakness needing strategies and policies to ensure patient-centered, safe, equitable, timely, and effective healthcare. Healthcare providers and policymakers in GCC countries can use the results to plan, assess, and improve care delivery. Trial registration: PROSPERO ID: CRD42022326842.

5.
BMC Geriatr ; 23(1): 251, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-37106330

RESUMO

BACKGROUND: In recent years, virtual reality (VR) has evolved from an alternative to a necessity in older adults for health, medical care, and social interaction. Upper limb (UL) motor skill, is an important ability in manipulating VR systems and represents the brain's regulation of movements using the UL muscles. In this study, we used a haptic-feedback Virtual Box and Block Test (VBBT) system and an Intrinsic Motivation Inventory (IMI) to examine age-related differences in UL motor performance and intrinsic motivation in VR use. The findings will be helpful for the development of VR applications for older adults. METHODS: In total, 48 young and 47 older volunteers participated in our study. The parameters including VBBT score, number of velocity peaks, velocity, grasping force and trajectory length were calculated to represent the task performance, manual dexterity, coordination, perceptive ability and cognitive ability in this study. RESULTS: Age-related differences could be found in all the parameters (all p <  0.05) in VR use. Regression analysis revealed that the task performance of young adults was predicted by the velocity and trajectory length (R2 = 64.0%), while that of older adults was predicted by the number of velocity peaks (R2 = 65.6%). Additionally, the scores of understandability, relaxation and tiredness were significantly different between the two groups (all p <  0.05). In older adults, the understandability score showed large correlation with the IMI score (|r| = 0.576, p <  0.001). In young adults, the correlation was medium (|r| = 0.342, p = 0.017). No significant correlation was found between the IMI score and VBBT score (|r| = 0.142, p = 0.342) in older adults, while a medium correlation (|r| = 0.342, p = 0.017) was found in young adults. CONCLUSIONS: The findings demonstrated that decreased smoothness in motor skills dominated the poor VR manipulation in older adults. The experience of understandability is important for older adults' intrinsic motivation in VR use.


Assuntos
Motivação , Realidade Virtual , Humanos , Idoso , Cognição , Extremidade Superior , Interface Usuário-Computador
6.
Asian J Androl ; 25(4): 487-491, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36861504

RESUMO

The penis is a vital organ of perception that transmits perceived signals to ejaculation-related centers. The penis consists of the glans penis and penile shaft, which differ considerably in both histology and innervation. This paper aims to investigate whether the glans penis or the penile shaft is the main source of sensory signals from the penis and whether penile hypersensitivity affects the whole organ or only part of it. The thresholds, latencies, and amplitudes of somatosensory evoked potentials (SSEPs) were recorded in 290 individuals with primary premature ejaculation using the glans penis and penile shaft as the sensory areas. The thresholds, latencies, and amplitudes of SSEPs from the glans penis and penile shaft in patients were significantly different (all P < 0.0001). The latency of the glans penis or penile shaft was shorter than average (indicating hypersensitivity) in 141 (48.6%) cases, of which 50 (35.5%) cases were sensitive in both the glans penis and penile shaft, 14 (9.9%) cases were sensitive in the glans penis only, and 77 (54.6%) cases were sensitive in the penile shaft only (P < 0.0001). There are statistical differences in the signals perceived through the glans penis and the penile shaft. Penile hypersensitivity does not necessarily mean that the whole penis is hypersensitive. We classify penile hypersensitivity into three categories, namely, glans penis, penile shaft, and whole-penis hypersensitivity, and we propose the new concept of penile hypersensitive zone.


Assuntos
Ejaculação Precoce , Masculino , Humanos , Ejaculação/fisiologia , Pênis/inervação , Potenciais Somatossensoriais Evocados/fisiologia
7.
Rev Gastroenterol Mex (Engl Ed) ; 88(1): 57-70, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36737343

RESUMO

Complementary feeding (CF) is defined as the feeding of infants that complements breastfeeding, or alternatively, feeding with a breast milk substitute, and is a process that is more than simply a guide as to what and how to introduce foods. The information provided by healthcare professionals must be up-to-date and evidence-based. Most of the recommendations that appear in the different international guidelines and position papers are widely applicable, but some must be regionalized or adapted to fit the conditions and reality of each geographic zone. The Nutrition Working Group of the Latin American Society for Pediatric Gastroenterology, Hepatology and Nutrition (LASPGHAN) summoned a group of experts from each of the society's member countries, to develop a consensus on CF, incorporating, whenever possible, local information adapted to the reality of the region. The aim of the present document is to show the results of that endeavor. Utilizing the Delphi method, a total of 34 statements on relevant aspects of CF were evaluated, discussed, and voted upon.


Assuntos
Gastroenterologia , Lactente , Criança , Feminino , Humanos , Cocos , Consenso , América Latina , Fenômenos Fisiológicos da Nutrição do Lactente
8.
Eur Child Adolesc Psychiatry ; 32(10): 1841-1852, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35585271

RESUMO

Among individuals with clinical high risk for psychosis (CHR), perceptive symptoms are more frequent but have less clinical significance in children/adolescents compared to adults. However, findings are based on clinical interviews relying on patient's recall capacity. Ecological momentary assessment (EMA) can be used to explore experiences in real-time in the subject's daily life. The aim of this study was to assess frequency and stability of (perceptive and non-perceptive) CHR symptoms and to explore potential age effects. EMA was used in a sample of an early detection for psychosis service in Bern, Switzerland (N = 66; 11-36 years). CHR symptoms were recorded in random time intervals for seven days: eight assessments per day per subject, minimum time between prompts set at 25 min. CHR symptoms were additionally assessed with semi-structured interviews including the 'Structured Interview for Psychosis-Risk Syndromes' and the 'Schizophrenia Proneness Instruments'. Mixed-effects linear regression analysis on the frequency of CHR symptoms revealed a significant effect of age group, and the interaction CHR symptoms x age group for both perceptive and non-perceptive symptoms. Further, regarding stability of CHR symptoms, there was a significant effect of the interaction CHR symptoms x age group for perceptive symptoms only. Based on EMA, perceptive CHR symptoms were more frequently reported but less stable in children/adolescents compared with adults. Together with previous findings, our finding of higher instability/variability of perceptive symptoms in younger persons might suggest that with advancing age and more stability of CHR symptoms, clinical relevance (reduced psychosocial functioning) may increase.


Assuntos
Transtornos Psicóticos , Esquizofrenia , Adulto , Adolescente , Criança , Humanos , Avaliação Momentânea Ecológica , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/psicologia , Esquizofrenia/diagnóstico , Suíça/epidemiologia , Sintomas Prodrômicos
9.
Front Hum Neurosci ; 17: 1228195, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38283095

RESUMO

In a recent review, we summarized the characteristics of perceptual-motor style in humans. Style can vary from individual to individual, task to task and pathology to pathology, as sensorimotor transformations demonstrate considerable adaptability and plasticity. Although the behavioral evidence for individual styles is substantial, much remains to be done to understand the neural and mechanical substrates of inter-individual differences in sensorimotor performance. In this study, we aimed to investigate the modulation of perceptual-motor style during locomotion at height in 16 persons with no history of fear of heights or acrophobia. We used an inexpensive virtual reality (VR) video game. In this VR game, Richie's Plank, the person progresses on a narrow plank placed between two buildings at the height of the 30th floor. Our first finding was that the static markers (head, trunk and limb configurations relative to the gravitational vertical) and some dynamic markers (jerk, root mean square, sample entropy and two-thirds power law at head, trunk and limb level) we had previously identified to define perceptual motor style during locomotion could account for fear modulation during VR play. Our second surprising result was the heterogeneity of this modulation in the 16 young, healthy individuals exposed to moving at a height. Finally, 56% of participants showed a persistent change in at least one variable of their skeletal configuration and 61% in one variable of their dynamic control during ground locomotion after exposure to height.

10.
Artigo em Inglês | MEDLINE | ID: mdl-36585492

RESUMO

Childhood-onset Obsessive-Compulsive Disorder (OCD) shows distinct comorbidity patterns and developmental pathways, as well as an increased risk of psychosis with respect to adult-onset forms. Nevertheless, little is known about the prodromal symptoms of psychosis in children and adolescents with a primary diagnosis of OCD. The present study was aimed at evaluating the occurrence of Cognitive-Perceptual basic symptoms (COPER) and high- risk criterion Cognitive Disturbances (COGDIS) in pediatric and adults OCD patients, verifying if they might vary according to the age of onset of OCD. The study included 90 outpatients with a primary diagnosis of obsessive-compulsive disorder. The study sample was collapsed into three groups according to the age at onset: 1) very early onset group (< 10 years); 2) early onset group (11-18 years); 3) adult-onset group (> 18 years). All patients were administered the Yale-Brown Obsessive- Compulsive Scale (Y-BOCS) and its Child version (CY-BOCS), the Schizophrenia Proneness Instrument-Adult (SPIA) and its Child and Adolescent version (SPI-CY) and the Social and Occupational Functioning Assessment Scale (SOFAS). COPER and COGDIS symptoms were positively associated with OCD severity and detectable, respectively, in 28.9 and 26.7% of our study sample. The very early onset group significantly had higher COPER and COGDIS symptoms than the adult-onset group. Our data suggest that COPER and COGDIS symptoms are frequent in obsessive patients, in particular in those with earlier onset; therefore, their detection in childhood-onset OCD may represent an early and specific indicator of psychotic vulnerability.

11.
Prog Rehabil Med ; 7: 20220020, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35495547

RESUMO

Background: There are no reports on the therapeutic application of perceptive exploration activity in patients with unilateral spatial neglect (USN). This study monitored the course of acute occupational therapy using perceptive exploration activities in a patient with USN who had difficulty in manipulating tools for daily living after a stroke. Case: A 70-year-old man was admitted to our hospital for conservative treatment of hemiparesis and USN caused by stroke. He was previously diagnosed with cerebral infarction due to middle cerebral artery occlusion. His main symptoms were hemiparesis, egocentric spatial neglect in personal space and peripersonal space, and allocentric neglect, which made it difficult to use tools for daily living. Within 24 h of admission, perceptive exploration activities were initiated as the main therapy in addition to preparatory therapies, such as the facilitation of selective movement of limbs affected by paralysis. These therapies were provided over a 30-day period in 40-min sessions, 5 days a week. This treatment resulted in improved test results for the Fugl-Meyer Assessment, Bisiach's body neglect and anosognosia scales, and the Behavioral Inattention Test. The Functional Independence Measure scores also improved with the improvement of neglect symptoms. Discussion: This case study monitored the improvements of egocentric spatial neglect and allocentric neglect during therapy using perceptive exploration activities in a patient with USN who had difficulty manipulating tools for daily living. The effectiveness of the therapy should be confirmed by increasing the sample size in future studies.

12.
JMIR Hum Factors ; 9(2): e26825, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35363150

RESUMO

BACKGROUND: Instrumented assessment of motor symptoms has emerged as a promising extension to the clinical assessment of several movement disorders. The use of mobile and inexpensive technologies such as some markerless motion capture technologies is especially promising for large-scale application but has not transitioned into clinical routine to date. A crucial step on this path is to implement standardized, clinically applicable tools that identify and control for quality concerns. OBJECTIVE: The main goal of this study comprises the development of a systematic quality control (QC) procedure for data collected with markerless motion capture technology and its experimental implementation to identify specific quality concerns and thereby rate the usability of recordings. METHODS: We developed a post hoc QC pipeline that was evaluated using a large set of short motor task recordings of healthy controls (2010 recordings from 162 subjects) and people with multiple sclerosis (2682 recordings from 187 subjects). For each of these recordings, 2 raters independently applied the pipeline. They provided overall usability decisions and identified technical and performance-related quality concerns, which yielded respective proportions of their occurrence as a main result. RESULTS: The approach developed here has proven user-friendly and applicable on a large scale. Raters' decisions on recording usability were concordant in 71.5%-92.3% of cases, depending on the motor task. Furthermore, 39.6%-85.1% of recordings were concordantly rated as being of satisfactory quality whereas in 5.0%-26.3%, both raters agreed to discard the recording. CONCLUSIONS: We present a QC pipeline that seems feasible and useful for instant quality screening in the clinical setting. Results confirm the need of QC despite using standard test setups, testing protocols, and operator training for the employed system and by extension, for other task-based motor assessment technologies. Results of the QC process can be used to clean existing data sets, optimize quality assurance measures, as well as foster the development of automated QC approaches and therefore improve the overall reliability of kinematic data sets.

13.
J Neurosci Methods ; 369: 109481, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35032498

RESUMO

BACKGROUND: Intrafascicular electrical stimulation has been extensively adopted to achieve sensory feedback for limb amputees. Axon-like carbon nanotube yarn (CNTy) electrodes with both promising flexibility and spatial selectivity index (SSI) can be fascinating alternatives to generate artificial somatosensation. NEW METHOD: Here we systematically disclose objective neuromodulation basis for artificial somatosensation through intrafascicular CNTy electrodes. CNTy electrodes with different exposed lengths were utilized for electrically stimulating tibial nerves in twelve rats. Somatosensory evoked potentials (SEPs) were recorded synchronously using an epidural thirty-channel electrode array. Spatiotemporal characteristics of SEPs were analyzed as current pulse amplitude (PA), pulse width (PW) and pulse frequency (PF) varied. RESULTS: The current thresholds at 1 Hz exhibit the lowest means when compared with those at 4 and 8 Hz for most CNTy electrodes (20/28). For all the electrodes, amplitudes of SEPs and activated areas of perceptive fields increase with PWs and PAs rising, and decrease remarkably with PFs from 1 to 8 Hz. Latencies of P1 and N1 of SEP peaks gradually reduced with PWs and PAs advancing. Considering high SSIs, relatively stable current thresholds, wider variation ranges of sensory magnitudes and optimal stability of perceptive fields, the L-200 µm electrodes are preferable for neuromodulation with PFs of 1 - 8 Hz, PWs of 100 - 800 µs and PAs of 2 - 64 µA. COMPARISON WITH EXISTING METHODS: New-type CNTy electrodes possess both promising flexibility and SSI when compared with other neural interfaces. We systematically explore objective neuromodulation basis for artificial somatosensation through CNTy electrodes for the first time. CONCLUSIONS: Significantly higher SSIs, lower current and charge thresholds exist for CNTy electrodes in comparison with other peripheral-nerve interfaces. This study can, for the first time, lay a solid neuromodulation foundation for CNTy electrodes to achieve fine sensory feedback.


Assuntos
Nanotubos de Carbono , Animais , Estimulação Elétrica , Eletrodos , Eletrodos Implantados , Potenciais Somatossensoriais Evocados , Nervos Periféricos/fisiologia , Ratos
14.
Adv Sci (Weinh) ; 9(5): e2104270, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34913616

RESUMO

Soft actuators with sensing capabilities are important in intelligent robots and human-computer interactions. However, present perceptive actuating systems rely on the integration of multiple functional units with complex circuit design. Here, a new-type pressure-perceptive actuator is reported, which integrates functions of sensing, actuating, and decision making at material level without complex combination. The actuator is composed of an actuating unit and a pressure-sensing unit, both of which are fabricated by carbon nanotube (CNT), silk, and polymer composite. On the one hand, the actuating unit can be driven by low voltages (<13 V), owing to a Joule-heating effect. On the other hand, the current passing the pressure-sensing unit can be controlled by tactile pressure. In the integrated actuator, it is able to control the deformation amplitude of actuating unit by applying different pressures on the pressure-sensing unit. A portable tactile-activated gripper is fabricated to operate an object through pressure control, demonstrating its application in tactile soft robots. Finally, three visual logic gates (AND, OR, and NOT) are proposed, which convert "tactile" inputs into "visible" deformation outputs, using the CNT-silk-based material for sensing and actuating in the decision-making process. This study provides a new path for intelligent soft robots and new-generation logic devices.


Assuntos
Nanotubos de Carbono , Robótica , Humanos , Polímeros , Tato
15.
Sensors (Basel) ; 21(21)2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34770424

RESUMO

Detection of unknown malware and its variants remains both an operational and a research challenge in the Internet of Things (IoT). The Internet of Medical Things (IoMT) is a particular type of IoT network which deals with communication through smart healthcare (medical) devices. One of the prevailing problems currently facing IoMT solutions is security and privacy vulnerability. Previous malware detection methods have failed to provide security and privacy. In order to overcome this issue, the current study introduces a novel technique called biserial correlative Miyaguchi-Preneel blockchain-based Ruzicka-index deep multilayer perceptive learning (BCMPB-RIDMPL). The present research aims to improve the accuracy of malware detection and minimizes time consumption. The current study combines the advantages of machine-learning techniques and blockchain technology. The BCMPB-RIDMPL technique consists of one input layer, three hidden layers, and one output layer to detect the malware. The input layer receives the number of applications and malware features as input. After that, the malware features are sent to the hidden layer 1, in which feature selection is carried out using point biserial correlation, which reduces the time required to detect the malware. Then, the selected features and applications are sent to the hidden layer 2. In that layer, Miyaguchi-Preneel cryptographic hash-based blockchain is applied to generate the hash value for each selected feature. The generated hash values are stored in the blockchain, after which the classification is performed in the third hidden layer. The BCMPB-RIDMPL technique uses the Ruzicka index to verify the hash values of the training and testing malware features. If the hash is valid, then the application is classified as malware, otherwise it is classified as benign. This method improves the accuracy of malware detection. Experiments have been carried out on factors such as malware detection accuracy, Matthews's correlation coefficient, and malware detection time with respect to a number of applications. The observed quantitative results show that our proposed BCMPB-RIDMPL method provides superior performance compared with state-of-the-art methods.


Assuntos
Blockchain , Internet das Coisas , Algoritmos , Atenção à Saúde , Aprendizado de Máquina
16.
J Agric Food Chem ; 69(34): 9895-9904, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34403583

RESUMO

The impact of commercial proanthocyanidic tannins on fruity pool of esters, representing the fruitiness of Bordeaux red wines, was assessed in model solutions. It was shown that the presence of tannins in the matrix significantly attenuated perception of fruity notes (p = 0.013). Physicochemical analysis demonstrated that the presence of proanthocyanidic tannins in dilute alcohol solution resulted in a decrease in ester partition coefficients and thus in a decrease in ester contents in the headspace (p < 0.05). This fact highlighted the changes that may occur in wines at a pre-sensory level, prior to sensory evaluation. Finally, a new sensory tool was developed, consisting in an ISO glass containing two compartments separated by a glass wall, providing a way to compare perceived odors according to whether or not the components of the odor mixtures were actually mixed in solution (p < 0.001). This new tool was used to demonstrate the impact and the only implication of pre-sensory level in the consequences of physical mixture between proanthocyanidic tannins and esters on their odor perception.


Assuntos
Vinho , Ésteres/análise , Frutas/química , Odorantes/análise , Taninos , Vinho/análise
17.
J Neurosci ; 41(37): 7813-7830, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34326144

RESUMO

Negative afterimages are perceptual phenomena that occur after physical stimuli disappear from sight. Their origin is linked to transient post-stimulus responses of visual neurons. The receptive fields (RFs) of these subcortical ON- and OFF-center neurons exhibit antagonistic interactions between central and surrounding visual space, resulting in selectivity for stimulus polarity and size. These two features are closely intertwined, yet their relationship to negative afterimage perception remains unknown. Here we tested whether size differentially affects the perception of bright and dark negative afterimages in humans of both sexes, and how this correlates with neural mechanisms in subcortical ON and OFF cells. Psychophysically, we found a size-dependent asymmetry whereby dark disks produce stronger and longer-lasting negative afterimages than bright disks of equal contrast at sizes >0.8°. Neurophysiological recordings from retinal and relay cells in female cat dorsal lateral geniculate nucleus showed that subcortical ON cells exhibited stronger sustained post-stimulus responses to dark disks, than OFF cells to bright disks, at sizes >1°. These sizes agree with the emergence of center-surround antagonism, revealing stronger suppression to opposite-polarity stimuli for OFF versus ON cells, particularly in dorsal lateral geniculate nucleus. Using a network-based retino-geniculate model, we confirmed stronger antagonism and temporal transience for OFF-cell post-stimulus rebound responses. A V1 population model demonstrated that both strength and duration asymmetries can be propagated to downstream cortical areas. Our results demonstrate how size-dependent antagonism impacts both the neuronal post-stimulus response and the resulting afterimage percepts, thereby supporting the idea of perceptual RFs reflecting the underlying neuronal RF organization of single cells.SIGNIFICANCE STATEMENT Visual illusions occur when sensory inputs and perceptual outcomes do not match, and provide a valuable tool to understand transformations from neural to perceptual responses. A classic example are negative afterimages that remain visible after a stimulus is removed from view. Such perceptions are linked to responses in early visual neurons, yet the details remain poorly understood. Combining human psychophysics, neurophysiological recordings in cats and retino-thalamo-cortical computational modeling, our study reveals how stimulus size and the receptive-field structure of subcortical ON and OFF cells contributes to the parallel asymmetries between neural and perceptual responses to bright versus dark afterimages. Thus, this work provides a deeper link from the underlying neural mechanisms to the resultant perceptual outcomes.


Assuntos
Pós-Imagem/fisiologia , Retina/fisiologia , Tálamo/fisiologia , Campos Visuais/fisiologia , Vias Visuais/fisiologia , Percepção Visual/fisiologia , Potenciais de Ação/fisiologia , Adulto , Animais , Gatos , Feminino , Humanos , Masculino , Neurônios/fisiologia , Adulto Jovem
18.
Front Psychol ; 12: 576608, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34122206

RESUMO

In the Origin of the work of art, Heidegger claimed that the work of art opens to us the truth of Being, the opening of the world. Two problematics arise from this. First, his idea of "world-disclosure" evoked a sense of everydayness (which captures, for me, the idea of credulism in perception). Second, the senses of truth, Being, and world are metaphysically condensed. Hence the question: how then could the "truth of Being" or the "world" that artworks reveal be experienced? Among other ways (mimesis, imagination, perception, etc.) by which artworks are experienced, I choose to examine perception since it confirms this idea of everydayness. The questions that confront us to this effect are: can perception lead us into, to encounter, this world opened by artworks? Does the nervous/visual system suffice to enter into that world in which the artist invites us? This is where Richir becomes important. In response to the first problem, he shows that the "perception" (experience) of artworks is beyond mere everydayness since artworks open for us a world that "never was" and "never will be" (i.e., "virtuality" and not a veridical sense of everydayness as captured in the perceptive act that is object-related). This is because the material stuff or object given in perception is neutralized by the phantasia to become what Richir calls Sache. This Sache is in itself a phenomenon that is disclosed in artworks. In response to the second problem, Richir shows how artworks cannot disclose just metaphysical categories of Being, truth, or world. The disclosure has to be phenomenological, corporeal, and affective. He therefore proposes another mode of "perception" beyond mere perception in a revolutionary interpretation of the husserlian "perceptive" phantasia. With this, he shows how the aforementioned metaphysical condensations are liveable in experience. I concretize this with an illustration from the theater. Finally, I suggest participation as a phenomenological approach that can make both Heidegger's and Richir's intuitions meaningful.

19.
Foods ; 10(2)2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33671408

RESUMO

Pyrazines are important compounds in soy sauce aroma type Baijiu (SSAB). In this work, a total of 16 pyrazines were analyzed using ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS) in SSAB. The quantitative results showed that 2,3,5,6-tetramethylpyrazine, 2,6-dimethylpyrazine and 2,3,5-trimethylpyrazine were the three most concentrated pyrazines. The highest odor activity value (OAV) was determined for 2-ethyl-3,5-dimethylpyrazine. Quantitative analysis combined with descriptive sensory analysis revealed that sub-threshold pyrazines (2,3-dimethylpyrazine, 2,3-diethylpyrazine, 2,3-diethyl-5-methylpyrazine and 2-acetyl-3-methylpyrazine) are significantly correlated with the roasted aroma in SSAB. Our study focused on the impact of sub-threshold pyrazines on the perception of roasted aroma in SSAB. The effect of the sub-threshold pyrazines was detected by the addition of various pyrazines in SSAB samples, despite their sub-threshold concentrations. Furthermore, the presence of sub-threshold pyrazines in dilute alcohol solution resulted in a significant reduction in the odor thresholds of supra-threshold pyrazines. Sensory investigation indicated that pyrazines have a synergistic effect on the perception of roasted aroma. The results highlighted the contribution of some pyrazines to the roasted aroma in SSAB despite their sub-threshold concentrations.

20.
Behav Res Methods ; 53(4): 1746-1761, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33569710

RESUMO

Pictures are often used as stimuli in several fields, such as psychology and neuroscience. However, co-occurring image-related properties might impact their processing, emphasizing the importance of validating such materials to guarantee the quality of research and professional practices. This is particularly relevant for pictures of common items because of their wide applicability potential. Normative studies have already been conducted to create and validate such pictures, yet most of them focused on stimulus without naturalistic elements (e.g., line drawings). Norms for real-world pictures of common items are rare, and their normative examination does not always simultaneously assess affective, semantic and perceptive dimensions, namely in the Portuguese context. Real-world pictures constitute pictorial representations of the world with realistic details (e.g., natural color or position), thus improving their ecological validity and their suitability for empirical studies or intervention purposes. Consequently, the establishment of norms for real-world pictures is mandatory for exploring their ecological richness and to uncover their impact across several relevant dimensions. In this study, we established norms for 596 real-world pictures of common items (e.g., tomato, drum) selected from existing databases and distributed into 12 categories. The pictures were evaluated on nine dimensions by a Portuguese sample. The results present the norms by item, by dimension and their correlations as well as cross-cultural analyses. RealPic is a culturally based dataset that offers systematic and flexible standards and is suitable for selecting stimuli while controlling for confounding effects in empirical tasks and interventional applications.


Assuntos
Semântica , Bases de Dados Factuais , Humanos
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