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The cognitive and neural bases of visual perception are typically studied using pictures rather than real-world stimuli. Unlike pictures, real objects are actionable solids that can be manipulated with the hands. Recent evidence from human brain imaging suggests that neural responses to real objects differ from responses to pictures; however, little is known about the neural mechanisms that drive these differences. Here, we tested whether brain responses to real objects versus pictures are differentially modulated by the "in-the-moment" graspability of the stimulus. In human dorsal cortex, electroencephalographic responses show a "real object advantage" in the strength and duration of mu (µ) and low beta (ß) rhythm desynchronization-well-known neural signatures of visuomotor action planning. We compared desynchronization for real tools versus closely matched pictures of the same objects, when the stimuli were positioned unoccluded versus behind a large transparent barrier that prevented immediate access to the stimuli. We found that, without the barrier in place, real objects elicited stronger µ and ß desynchronization compared to pictures, both during stimulus presentation and after stimulus offset, replicating previous findings. Critically, however, with the barrier in place, this real object advantage was attenuated during the period of stimulus presentation, whereas the amplification in later periods remained. These results suggest that the "real object advantage" is driven initially by immediate actionability, whereas later differences perhaps reflect other, more inherent properties of real objects. The findings showcase how the use of richer multidimensional stimuli can provide a more complete and ecologically valid understanding of object vision.
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Eletroencefalografia , Percepção Visual , Córtex Cerebral , Humanos , Estimulação LuminosaRESUMO
In visual search, the presence of a salient, yet task-irrelevant, distractor in the stimulus array interferes with target selection and slows down performance. Neuroimaging data point to a key role of the frontoparietal dorsal attention network in dealing with visual distractors; however, the respective roles of different nodes within the network and their hemispheric specialization are still unresolved. Here, we used transcranial magnetic stimulation (TMS) to evaluate the causal role of two key regions of the dorsal attention network in resisting attentional capture by a salient singleton distractor: the frontal eye field (FEF) and the cortex within the intraparietal sulcus (IPS). The task of the participants (male/female human volunteers) was to discriminate the pointing direction of a target arrow while ignoring a task-irrelevant salient distractor. Immediately after stimulus onset, triple-pulse 10 Hz TMS was delivered either to IPS or FEF on either side of the brain. Results indicated that TMS over the right FEF significantly reduced the behavioral cost engendered by the salient distractor relative to left FEF stimulation. No such effect was obtained with stimulation of IPS on either side of brain. Interestingly, this FEF-dependent reduction in distractor interference interacted with the contingent trial history, being maximal when no distractor was present on the previous trial relative to when there was one. Our results provide direct causal evidence that the right FEF houses key mechanisms for distractor filtering, pointing to a pivotal role of the frontal cortex of the right hemisphere in limiting interference from an irrelevant but attention-grabbing stimulus.SIGNIFICANCE STATEMENT Visually conspicuous stimuli attract our attention automatically and interfere with performance by diverting resources away from the main task. Here, we applied transcranial magnetic stimulation over four frontoparietal cortex locations (frontal eye field and intraparietal sulcus in each hemisphere) to identify regions of the dorsal attention network that help limit interference from task-irrelevant, salient distractors. Results indicate that the right FEF participates in distractor-filtering mechanisms that are recruited when a distracting stimulus is encountered. Moreover, right FEF implements adjustments in distraction-filtering mechanisms following recent encounters with distractors. Together, these findings indicate a different hemispheric contribution of the left versus right dorsal frontal cortex to distraction filtering. This study expands our understanding of how our brains select relevant targets in the face of task-irrelevant, salient distractors.
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Atenção/fisiologia , Lobo Frontal/fisiologia , Lobo Parietal/fisiologia , Estimulação Magnética Transcraniana , Percepção Visual/fisiologia , Mapeamento Encefálico/métodos , Feminino , Humanos , Masculino , Adulto JovemRESUMO
Ultimately, we aim to generalize and translate scientific knowledge to the real world, yet current understanding of human visual perception is based predominantly on studies of two-dimensional (2-D) images. Recent cognitive-behavioral evidence shows that real objects are processed differently to images, although the neural processes that underlie these differences are unknown. Because real objects (unlike images) afford actions, they may trigger stronger or more prolonged activation in neural populations for visuo-motor action planning. Here, we recorded electroencephalography (EEG) when human observers viewed real-world three-dimensional (3-D) objects or closely matched 2-D images of the same items. Although responses to real objects and images were similar overall, there were critical differences. Compared to images, viewing real objects triggered stronger and more sustained event-related desynchronization (ERD) in the µ frequency band (8-13â¯Hz) - a neural signature of automatic motor preparation. Event-related potentials (ERPs) revealed a transient, early occipital negativity for real objects (versus images), likely reflecting 3-D stereoscopic differences, and a late sustained parietal amplitude modulation consistent with an 'old-new' memory advantage for real objects over images. Together, these findings demonstrate that real-world objects trigger stronger and more sustained action-related brain responses than images do. The results highlight important similarities and differences between brain responses to images and richer, more ecologically relevant, real-world objects.
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Córtex Cerebral/fisiologia , Percepção Visual/fisiologia , Adulto , Eletroencefalografia/métodos , Potenciais Evocados/fisiologia , Feminino , Humanos , Masculino , Estimulação Luminosa , Desempenho Psicomotor/fisiologia , Adulto JovemRESUMO
Given the information overload often imparted to human cognitive-processing systems, suppression of irrelevant and distracting information is essential for successful behavior. Using a hybrid block/event-related fMRI design, we characterized proactive and reactive brain mechanisms for filtering distracting stimuli. Participants performed a flanker task, discriminating the direction of a target arrow in the presence versus absence of congruent or incongruent flanking distracting arrows during either Pure blocks (distracters always absent) or Mixed blocks (distracters on 80% of trials). Each Mixed block had either 20% or 60% incongruent trials. Activations in the dorsal frontoparietal attention network during Mixed versus Pure blocks evidenced proactive (blockwise) recruitment of a distraction-filtering mechanism. Sustained activations in right middle frontal gyrus during 60% Incongruent blocks correlated positively with behavioral indices of distraction-filtering (slowing when distracters might occur) and negatively with distraction-related behavioral costs (incongruent vs congruent trials), suggesting a role in coordinating proactive filtering of potential distracters. Event-related analyses showed that incongruent trials elicited greater reactive activations in 20% (vs 60%) Incongruent blocks for counteracting distraction and conflict, including in the insula and anterior cingulate. Context-related effects in occipitoparietal cortex consisted of greater target-evoked activations for distracter-absent trials (central-target-only) in Mixed versus Pure blocks, suggesting enhanced attentional engagement. Functional-localizer analyses in V1/V2/V3 revealed less distracter-processing activity in 60% (vs 20%) Incongruent blocks, presumably reflecting tonic suppression by proactive filtering mechanisms. These results delineate brain mechanisms underlying proactive and reactive filtering of distraction and conflict, and how they are orchestrated depending on distraction probability, thereby aiding task performance. Significance statement: Irrelevant stimuli distract people and impair their attentional performance. Here, we studied how the brain deals with distracting stimuli using a hybrid block/event-related fMRI design and a task that varied the probability of the occurrence of such distracting stimuli. The results suggest that when distraction is likely, a region in right frontal cortex proactively implements attentional control mechanisms to help filter out any distracting stimuli that might occur. In contrast, when distracting input occurs infrequently, this region is more reactively engaged to help limit the negative consequences of the distracters on behavioral performance. Our results thus help illuminate how the brain flexibly responds under differing attentional demands to engender effective behavior.
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Atenção/fisiologia , Encéfalo/fisiologia , Conflito Psicológico , Imageamento por Ressonância Magnética/métodos , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Adolescente , Adulto , Mapeamento Encefálico/métodos , Feminino , Humanos , Masculino , Estimulação Luminosa/métodos , Adulto JovemRESUMO
The crossmodal congruency task is a consolidated paradigm for investigating interactions between vision and touch. In this task, participants judge the elevation of a tactile target stimulus while ignoring a visual distracter stimulus that may occur at a congruent or incongruent elevation, thus engendering a measure of visuo-tactile interference (crossmodal congruency effect, CCE). The CCE reflects perceptual, attentional, and response-related factors, but their respective roles and interactions have not been set out yet. In two experiments, we used the original version of the crossmodal congruency task as well as ad hoc manipulations of the experimental setting and of the participants' posture for characterizing the contributions of multisensory integration, body-mediated attention, and response conflict to the CCE. Results of the two experiments consistently showed that the largest amount of variance in the CCE is explained by the reciprocal elevation of visual and tactile stimuli. This finding is compatible with a major role of response conflict for the CCE. Weaker yet distinguishable contributions come from multisensory integration, observed in the absence of response conflict, and from hand-mediated attentional binding, observed with the modified posture and in the presence of response conflict. Overall, this study informs the long-standing debate about mechanisms underlying the CCE by revealing that the visuo-tactile interference in this task is primarily due to the competition between opposite response tendencies, with an additional contribution of multisensory integration and hand-mediated attentional binding.
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Atenção/fisiologia , Conflito Psicológico , Desempenho Psicomotor/fisiologia , Percepção do Tato/fisiologia , Percepção Visual/fisiologia , Adulto , Análise de Variância , Feminino , Humanos , Masculino , Estimulação Luminosa , Tempo de Reação/fisiologia , Tato , Adulto JovemRESUMO
AIMS: To evaluate a multilevel program to raise awareness of the risks of prenatal exposure to alcohol in the area of Treviso (Italy). The program started in 2008 and consists of an action-research experience involving health professionals of maternal-child services, and in the campaign 'Mamma Beve Bimbo Beve', targeted to the childbearing-aged population. METHODS: A comparative study was carried out in 2013. Surveys using semi-structured self-report questionnaires were carried out among professionals and pregnant women in Treviso, and among control groups belonging to another local area of Italy (Verona). The questionnaires investigated awareness and opinions about alcohol and pregnancy, as well as sources and kind of information provided and received. RESULTS: Health professionals in Treviso, who had been exposed both to the action-research experience and to the campaign, showed a more rational approach to alcohol than colleagues in the control group, and were more aware and sensitized about the risks of alcohol consumption during pregnancy. Physicians and midwives had a higher probability of having advised pregnant women to abstain from alcohol in Treviso. Pregnant women in Treviso, who had received information through the campaign and from professionals, had a higher probability of having received only correct advice about the issue of alcohol and pregnancy, but did not hold perceptions different to women in Verona. CONCLUSIONS: The multilevel program carried out in the Treviso area was effective in increasing awareness and improving attitudes towards the risks of alcohol use during pregnancy among local healthcare professionals, compared with the control group.
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Consumo de Bebidas Alcoólicas/efeitos adversos , Conhecimentos, Atitudes e Prática em Saúde , Tocologia/educação , Médicos/psicologia , Gestantes/psicologia , Educação Pré-Natal/métodos , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Gravidez , Características de Residência , Adulto JovemRESUMO
AIMS: To assess the impact of the advertising image used in the health communication campaign 'Mummy Drinks Baby Drinks', aimed to raise awareness about the effects of drinking alcohol during pregnancy in the childbearing-aged population of the Local Health Authority of Treviso (Italy). The image depicted a foetus inside a glass of a local alcoholic drink. METHODS: A survey using a semi-structured self-reported questionnaire was carried out. The questionnaire was administered to a consecutive series of 690 parents or caregivers who accompanied children aged 0-2 years in the vaccination clinics of the Local Health Unit, during a 30-day period 1 year after the start of the campaign. The questionnaire measured the level of exposure to the image, emotional reactions and awareness of the health messages conveyed by the image. RESULTS: Overall, 84% of the respondents said that they remembered the image. Almost all (93%) recalled the warning message and 53% recalled the health behaviours suggested by the campaign. The image generally seemed to arouse a high emotive impact: 38% indicated distress and 40% liking as a general opinion, while â¼50% expressed distress emotions and 13% were pleasantly affected when reflecting on the feelings evoked. We did not find unequivocal relationships between the level and kind of emotional reactions and the recalling of the health behaviours. CONCLUSION: The image obtained a high level of visibility. It was effective in spreading the health message conveyed by the campaign, regardless of the level and kind of emotive impact evoked.
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Publicidade/métodos , Consumo de Bebidas Alcoólicas/psicologia , Conscientização , Comunicação , Conhecimentos, Atitudes e Prática em Saúde , Promoção da Saúde/métodos , Adulto , Consumo de Bebidas Alcoólicas/efeitos adversos , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Gravidez , Estudos Prospectivos , Inquéritos e Questionários , Adulto JovemRESUMO
The aim of the present study was to uncover the temporal dynamics of face recognition as a function of reward. Event-related potentials (ERPs) were recorded during the encoding and the subsequent old/new memory test in response to faces that could be associated with a monetary reward. The behavioral results showed that faces associated with reward at both encoding and retrieval were recognized better than the unrewarded ones. ERP responses highlighted that successful encoding predictive of subsequent memory was greater for faces associated with reward than for faces without reward-driven motivational learning. At retrieval, an early positive-going component was elicited for potentially rewarded faces on frontal regions, while the occipito-temporal N170 component showed priming effects as a function of reward. Later on, larger centro-parietal ERP components, related to recognition memory, were found selectively for reward-associated faces. Remarkably, electrophysiological responses varied in a graded manner, with the largest amplitude yielded by faces with double reward, followed by faces associated with reward only at encoding. Taken together, the present data show that the processing of outcome expectations affects face structural encoding and increases memory efficiency, yielding a robust and sustained modulation over frontal and temporal areas where reward and memory mechanisms operate in conjunction.
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Córtex Cerebral/fisiologia , Potenciais Evocados/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Reconhecimento Psicológico/fisiologia , Recompensa , Adulto , Eletroencefalografia , Face , Feminino , Humanos , Masculino , Tempo de Reação/fisiologiaRESUMO
Site conditions and forest management affect dendrometric parameters of chestnut (Castanea sativa Mill.) coppices, but there is modest knowledge on the effect of stand dendrometric characters on physical and mechanical wood characteristics. The aim of this study was to verify these relationships in chestnut coppices that were 12-14 years old. Wood density, compression and bending strength, shrinkages were measured on shoots of five different stand in a vulcanic site in Monte Amiata (Central - Italy). Investigated stands differ in number of stools/ha and dominant height, diameter/basal area of the shoots. The main difference in the physical characters among the stands is density. The initial results of the study showed that physical, mechanical wood characters are more dependent by the shoot than by the site. There is a positive relationships between the number of stools/ha and density and a negative one among shoot dominant height and basal area with wood density. Spectroscopic profile by FTIR has not showed relevant differences among the stands. Wood anatomy has showed the breakpoint at cellular level.
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Agricultura/métodos , Fagaceae/metabolismo , Fagaceae/fisiologia , Conservação dos Recursos Naturais/métodos , Agricultura Florestal/métodos , Florestas , Itália , Árvores/crescimento & desenvolvimento , Madeira/análiseRESUMO
Gastrointestinal complications (GICs) represent the major cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Differential diagnosis of GICs is of paramount importance since early and reliable identification of graft-versus-host disease (GVHD) is essential for a correct management of the patients. The aim of the present retrospective study was to evaluate the occurrence of GICs after allo-HSCT and to assess the diagnostic performance of a quick endoscopic and histological assessment in the differential diagnosis between GVHD and other GI conditions. Between January 2015 and August 2019, 122 consecutive patients receiving an allo-HSCT were managed by an interdisciplinary team, supported by a dedicated endoscopic service. Clinical, therapeutic, endoscopic and histological data were analyzed for each patient. Collectively, 94 of the patients developed GICs (77%). A moderate-severe mucositis was the most frequent complication, occurring in 79 patients (84%). Acute GI-GVHD was diagnosed in 35 patients (37% of whom with GICs) and 19 of them with a moderate-severe grade. Infective acute colitis developed in eight patients, mainly due to Clostridium difficile (CD) and Cytomegalovirus infections (8.5%). Rectal biopsy showed the highest sensitivity and specificity (80% and 100%, respectively). However, when biopsy procedures were guided by symptoms and performed on apparently intact mucosa, upper histology also provided a high negative predictive value (80%). Our multidisciplinary approach with a quick endoscopic/histologic investigation in the patients receiving an allo-HSCT and who suffered GICs could improve diagnostic and therapeutic management in this challenging setting.
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Background and study aims COVID-19 has dramatically impacted endoscopy practice because upper endoscopy procedures can be aerosol-generating. Most elective procedures have been rescheduled. Endoscopic retrograde cholangiopancreatography (ERCP) is frequently performed in emergency or urgent settings in which rescheduling is not possible. We evaluated the impact of the COVID-19 pandemic on ERCP in Italy during the SARS-CoV-2 lockdown, in areas with high incidence of COVID-19. Patients and methods We performed a retrospective survey of centers performing ERCP in high COVID-19 prevalence areas in Italy to collect information regarding clinical data from patients undergoing ERCP, staff, case-volume and organization of endoscopy units from March 8, 2020 to April 30, 2020. Results We collected data from 31 centers and 804 patients. All centers adopted a triage and/or screening protocol for SARS-CoV-2 and performed follow-up of patients 2 weeks after the procedure. ERCP case-volume was reduced by 44.1â% compared to the respective 2019 timeframe. Of the 804 patients undergoing ERCP, 22 (2.7â%) were positive for COVID-19.âAdverse events occurred at a similar rate to previously published data. Of the patients, endoscopists, and nurses, 1.6â%, 11.7â%, and 4.9â%, respectively, tested positive for SARS-CoV-2âat follow up.âOnly 38.7â% of centers had access to a negative-pressure room for ERCP. Conclusion The case-volume reduction for ERCP during lockdown was lower than for other gastrointestinal endoscopy procedures. No definitive conclusions can be drawn about the percentage of SARS-CoV-2-positive patients and healthcare workers observed after ERCP. Appropriate triage and screening of patients and adherence to society recommendations are paramount.
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Visual search can be guided by top-down and bottom-up processes, with either one dominating the other depending on the task (e.g., feature versus conjunction). Moreover, different search tasks bring about different expectations about the type, or frequency, of distractor stimuli. These expectations could promote top-down "task-sets" that may impact performance even when distractors are temporarily absent. Here, we characterized the role and extent of recruitment of proactive top-down processes for distractor expectation in feature and conjunction search. Participants conducted feature and conjunction search tasks for a visual target among distractors, which were either frequently presented or completely absent. The effects of the recruitment of proactive top-down processes for distractor expectation entailed slower responses, yet more accurate, on distractor-absent trials in the frequent-distractor (versus no-distractor) context of both tasks. These effects were larger in the conjunction versus feature task and were not impacted by stimulus duration and time pressure (short/present in Experiment 1, unlimited/absent in Experiment 2, respectively). Results were replicated when the presence/absence of distractors at each trial was fully predictable (Experiment 3), and when several parameters of visual search were changed (Experiment 4). Our findings indicate that top-down task-sets related to distractor expectation entail performance costs and benefits in visual search. These effects occur throughout task blocks rather than trial-to-trial, are modulated by search type, and confirm that proactive top-down processes intervene in feature search.
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Atenção , Motivação , Humanos , Tempo de Reação , Percepção VisualRESUMO
Value-directed strategic processing is an ability that appears to be relatively preserved with aging, but the neurophysiological mechanisms underlying strategic processing in older adults are not well understood. The current study examined age-related spectral power differences in EEG oscillations linked to processing of high-value versus low-value information in a value-directed strategic processing task in 24 younger adults (mean age: 22.4 ± 1.2 years) and 24 older adults (mean age: 63.2 ± 6.4 years). Both groups exhibited comparable strategic processing ability behaviorally with preferential recall of high- compared to low-value words. Both groups exhibited comparable theta band power with greater synchronization for low- compared to high-value words, but age-related differences in processing were noted in alpha band power. Older adults showed more prolonged alpha desynchronization for high- compared to low-value words relative to younger adults. This neurophysiological modulation in the alpha band in older adults might reflect a compensatory neural mechanism or increased effort linked to selective engagement of neural resources, allowing them to perform similarly to younger adults behaviorally on a value-directed strategic processing task.
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Fatores Etários , Cognição/fisiologia , Rememoração Mental/fisiologia , Envelhecimento/fisiologia , Ritmo alfa/fisiologia , Encéfalo/fisiologia , Eletroencefalografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ritmo Teta/fisiologia , Adulto JovemRESUMO
Sustainability and ecotoxicity issues call for innovations regarding eco-friendly adhesives in the production of biocomposite wood materials, and solutions involving nano-scale and bio-based compounds represent a valid and promising target. One possible approach is to increase the performance of adhesives such as polyvinyl acetate (PVAc) or melamine-urea-formaldehyde (MUF) by means of nanoparticles in order to obtain a material with better mechanical and environmental resistance. When applying cellulose-based nanoparticles or tannin, the concept of a circular economy is successfully implemented into the forest/wood value chain, and chances are created to develop new value chains using byproducts of forestry operations. In this study, assortments coming from young sweet chestnut (Castanea sativa Mill.) coppice stands were utilized for the preparation of single lap joint assemblies using different commercial adhesives (PVAc, MUF) and cellulose nanocrystals (CNC) and tannin as additives. The results showed that addition of CNC and tannin to PVAc glue increased tensile shear strength in lap joint tests presenting a promising base for future tests regarding the addition of CNC and tannin in MUF or PVAc adhesive formulations. Unfortunately, the tested bio-based additives did not reveal the same encouraging results when tested in the wet state.
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Robust perception requires efficient integration of information from our various senses. Much recent electrophysiology points to neural areas responsive to multisensory stimulation, particularly audiovisual stimulation. However, psychophysical evidence for functional integration of audiovisual motion has been ambiguous. In this study we measure perception of an audiovisual form of biological motion, tap dancing. The results show that the audio tap information interacts with visual motion information, but only when in synchrony, demonstrating a functional combination of audiovisual information in a natural task. The advantage of multimodal combination was better than the optimal maximum likelihood prediction.
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Percepção Auditiva/fisiologia , Percepção de Movimento/fisiologia , Estimulação Acústica , Adulto , Discriminação Psicológica/fisiologia , Feminino , Humanos , Estimulação Luminosa , PsicofísicaRESUMO
OBJECTIVE: Electroencephalography (EEG) is widely used by clinicians, scientists, engineers and other professionals worldwide, with an increasing number of low-cost, commercially-oriented EEG systems that have become available in recent years. One such system is the Cognionics Quick-20 (Cognionics Inc., San Diego, USA), which uses dry electrodes and offers the convenience of portability thanks to its built-in amplifier and wireless connection. Because of such characteristics, this system has been used in several applications for both clinical and basic research studies. However, an investigation of the quality of the signals that are recorded using this system has not yet been reported. APPROACH: To bridge this gap, here we conducted a systematic comparison of signal quality between the Cognionics Quick-20 system and the Brain Products actiCAP/actiCHamp (Brain Products GmbH, Munich, Germany), a state-of-the-art, wet-electrode, research-oriented EEG system. Resting-state EEG data were recorded from twelve human participants at rest in eyes open and eyes closed conditions. For both systems we evaluated the similarity of mean recorded power spectral density, and detection of alpha suppression associated with eyes open relative to eyes closed. MAIN RESULTS: Power spectral densities were highly correlated across systems, with only minor topographical variability across the scalp. Both systems recorded alpha suppression during eyes open relative to eyes closed conditions. SIGNIFICANCE: These results attest to the robustness and reliability of the dry-electrode Cognionics system relatively to the widely used Brain Products laboratory EEG system, and thus validate its utility for clinical and basic research purposes, at least in studies in which participants do not move.
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Encéfalo/fisiologia , Eletrodos/normas , Eletroencefalografia/instrumentação , Eletroencefalografia/normas , Descanso/fisiologia , Tecnologia sem Fio/normas , Amplificadores Eletrônicos/normas , Feminino , Humanos , Masculino , Tecnologia sem Fio/instrumentaçãoRESUMO
Here we present a collection of electroencephalographic (EEG) data recorded from 24 observers (14 females, 10 males, mean age: 25.4) while observing individually-presented stimuli comprised of 96 real-world objects, and 96 images of the same items printed in high-resolution. EEG was recorded from 128 scalp channels. Six additional external electrodes were used to record vertical and horizontal electrooculogram, as well as the signal from the left and right mastoid. EEG has been pre-processed, segmented in non-overlapping epochs, and independent component analysis (ICA) has been conducted to reject artifacts. Moreover, supplemental pre-processing steps have been completed to facilitate the analysis of event-related potentials (ERP). These data are linked to the article "Distinct visuo-motor brain dynamics for real-world objects versus planar images". Alongside this data we provide the custom-written Matlab® code that can be used to fully reproduce all analyses and figures presented in the linked research article.
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Distractor suppression, or the ability to disregard salient distractors while dealing with task-relevant information, is a key component of selective attention. Recent research has shown that distractor suppression can take place in different circumstances and present itself in different guises, which is presumably paralleled by a multiplicity of underlying neural mechanisms. In this review article, we discuss a number of central themes concerning distractor suppression and the underlying neural mechanisms, and also highlight several unresolved issues that will have to be addressed in future investigations.
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Atenção , Encéfalo/fisiologia , Percepção Visual , Sinais (Psicologia) , Humanos , Imageamento por Ressonância Magnética , Estimulação LuminosaRESUMO
Strategic processing allows for value-based preferential encoding of information. Event-related spectral perturbations can provide insights into neural processes linked to the different aspects of strategic processing. This study examined theta and alpha band power differences linked to processing of high- versus low-value information. Thirty-three young adults (17 F; mean age: 21.2 ± 1.5 years) completed a value-directed word list learning task. The task consisted of five word lists that each contained a unique set of high- and low-value words that were visually presented one at a time and EEG corresponding to these words were examined. To encourage strategic processing, participants were informed that after each list they would be asked to recall as many words as possible with their goal being to maximize their score. Overall, participants recalled more high-value words for each of the five lists as compared to low-value words, which supports that participants engaged in strategic processing. Frontal theta band power showed greater positivity during processing of low- compared to high-value words, whereas parietal alpha band power showed greater negativity during processing of high- compared to low-value words. These findings suggest that theta and alpha bands index different aspects of strategic processing, namely inhibition and selective attention, and have future applications for understanding the effects of aging and brain diseases/disorders.
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Ritmo alfa/fisiologia , Atenção/fisiologia , Córtex Cerebral/fisiologia , Inibição Psicológica , Reconhecimento Visual de Modelos/fisiologia , Ritmo Teta/fisiologia , Aprendizagem Verbal/fisiologia , Adolescente , Adulto , Potenciais Evocados/fisiologia , Feminino , Humanos , Masculino , Leitura , Adulto JovemRESUMO
OBJECTIVE: Arthritis is the most frequent extra-intestinal manifestation in patients with inflammatory bowel diseases (IBD). The coexistence of intestinal and articular inflammation advocates the need for a multidisciplinary management of patients with IBD-associated spondyloarthritis. METHODS: Consecutive IBD patients were evaluated jointly by the gastroenterologist and the rheumatologist in a combined clinic. All the patients were assessed and screened for articular involvement, disease activity and health related quality of life. After the prescription of a shared treatment, patients with spondyloarthritis were followed up for 24â¯months. RESULTS: Two hundred sixty-two IBD patients, including 80 who were classified as affected by spondyloarthritis according to the ASAS criteria, were included in the study. At baseline, patients with both IBD and spondyloarthritis showed worse quality of life in both the physical and mental domains. The multidisciplinary management provided a significant improvement of gastrointestinal and articular manifestations, as well as the health-related quality of life. Moreover, global and gastrointestinal-specific quality of life significantly correlated with articular disease activity. CONCLUSION: The multidisciplinary management significantly improves both articular and gastrointestinal disease activities and the quality of life of patients with IBD-associated spondyloarthritis. An appropriate screening strategy and the integrated management of these patients should be encouraged and employed in clinical practice.