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1.
Psychol Res ; 88(3): 837-851, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37878155

RESUMO

The Spatial-Numerical Association of Response Codes (SNARC) effect consists in faster left-/right-key responses to small/large numbers. (Bächtold et al., Neuropsychologia 36:731-735, 1998) reported the reversal of this effect after eliciting the context of a clockface-where small numbers are represented on the right and large numbers on the left. The present study investigates how the salience of a particular spatial-numerical context, which reflects the level of activation of the context in working memory, can alter Spatial Numerical Associations (SNAs). Four experiments presented the clockface as context and gradually increased its salience using different tasks. In the first two experiments (low salience), the context was presented at the beginning of the experiment and its retrieval was not required to perform the tasks (i.e., random number generation in Experiment 1, magnitude classification and parity judgement in Experiment 2). Results revealed regular left-to-right SNAs, unaffected by the context. In Experiment 3 (medium salience), participants performed magnitude classification and parity judgement (primary task), and a Go/No-go (secondary task) which required the retrieval of the context. Neither the SNARC effect nor a reversed-SNARC emerged, suggesting that performance was affected by the context. Finally, in Experiment 4 (high salience), the primary task required participants to classify numbers based on their position on the clockface. Results revealed a reversed SNARC, as in (Bächtold et al., Neuropsychologia 36:731-735, 1998). In conclusion, SNARC is disrupted when the context is retrieved in a secondary task, but its reversal is observed only when the context is relevant for the primary task.


Assuntos
Julgamento , Percepção Espacial , Humanos , Tempo de Reação/fisiologia , Percepção Espacial/fisiologia , Julgamento/fisiologia , Memória de Curto Prazo
2.
J Nanobiotechnology ; 21(1): 329, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37710290

RESUMO

BACKGROUND: Alzheimer's disease (AD) is the leading cause of dementia and loss of autonomy in the elderly, implying a progressive cognitive decline and limitation of social activities. The progressive aging of the population is expected to exacerbate this problem in the next decades. Therefore, there is an urgent need to develop quantitative diagnostic methodologies to assess the onset the disease and its progression especially in the initial phases. RESULTS: Here we describe a novel technology to extract one of the most important molecular biomarkers of AD (Aß1-42) from a clinically-relevant volume - 100 µl - therein dispersed in a range of concentrations critical for AD early diagnosis. We demonstrate that it is possible to immunocapture Aß1-42 on 20 nm wide magnetic nanoparticles functionalized with hyperbranced KVLFF aptamers. Then, it is possible to transport them through microfluidic environments to a detection system where virtually all (~ 90%) the Aß1-42 molecules are concentrated in a dense plug of ca.50 nl. The technology is based on magnetic actuation by permanent magnets, specifically designed to generate high gradient magnetic fields. These fields, applied through submillimeter-wide channels, can concentrate, and confine magnetic nanoparticles (MNPs) into a droplet with an optimized shape that maximizes the probability of capturing highly diluted molecular biomarkers. These advancements are expected to provide efficient protocols for the concentration and manipulation of molecular biomarkers from clinical samples, enhancing the accuracy and the sensitivity of diagnostic technologies. CONCLUSIONS: This easy to automate technology allows an efficient separation of AD molecular biomarkers from volumes of biological solutions complying with the current clinical protocols and, ultimately, leads to accurate measurements of biomarkers. The technology paves a new way for a quantitative AD diagnosis at the earliest stage and it is also adaptable for the biomarker analysis of other pathologies.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Idoso , Humanos , Doença de Alzheimer/diagnóstico , Envelhecimento , Campos Magnéticos , Microfluídica
3.
Psychol Res ; 87(2): 636-653, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35552515

RESUMO

Recent findings on emotion comparison show a typical pattern of motor reactivity rising from attentional capture. When pairs of emotional faces are presented simultaneously, the most intense emotional face is recognized faster (Emotional Semantic Congruency-ESC effect). Furthermore, a global response speed advantage for emotional pairs with positive rather than negative average emotion intensity is observed (i.e., emotional size effect), with the choice for the happiest face resulting in a faster response than the choice for the angriest face within the pair (i.e., the happiness advantage). In two experiments, we asked whether these effects are orientation dependent, and thus linked to whether face processing is holistic or part-based. Participants were asked to choose the angriest/happiest face in emotional pairs displayed either in upright or inverted orientation and including (Experiment 1) or not including (Experiment 2) a neutral face. Beyond an overall facilitation for upright relative to inverted pairs, results showed orientation independent ESC and emotional size effects. Furthermore, the happiness advantage was present in emotional pairs of Experiment 2 but not in emotional pairs of Experiment 1, independently from face orientation. Together, results suggest that attentional capture in emotion comparison is immaterial on the type of face processing, being orientation invariant.


Assuntos
Emoções , Expressão Facial , Humanos , Emoções/fisiologia , Atenção/fisiologia , Felicidade , Ira
4.
J Trauma Stress ; 34(4): 880-888, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33772886

RESUMO

The Impact of Event Scale-Revised (IES-R) is a widely used self-report questionnaire used to assess symptoms of posttraumatic stress disorder (PTSD). Although the IES-R has been translated and validated in multiple languages, no previous version has employed the Arabic dialect commonly spoken in Syria. The present work aimed to assess the psychometric properties of a Syrian Arabic version of the IES-R. Syrian citizens (N = 288) living in refugee camps in Turkey were administered the Syrian Arabic IES-R as part of a humanitarian aid project focused on providing psychological assistance. The data were analyzed with respect to 10 previously published factor solutions. We found that the best-fitting model was a four-factor structure that included factors involving Avoidance-Numbing, Intrusion, Hyperarousal, and Sleep Disturbance. The model showed strong measurement invariance between male and female subsamples, allowing for meaningful comparisons of the factor means. Overall, the present findings support the validity of a new version of the IES-R, which can be used by both researchers and clinicians responding to the urgent need for psychological care for Syrian refugees fleeing war-related violence.


Assuntos
Refugiados , Transtornos de Estresse Pós-Traumáticos , Feminino , Humanos , Idioma , Masculino , Psicometria , Síria
5.
Psychol Res ; 85(3): 1272-1291, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32166368

RESUMO

Previous work on the direct speed-intensity association (SIA) on comparative judgement tasks involved spatially distributed responses over spatially distributed stimuli with high motivational significance like facial expressions of emotions. This raises the possibility that the inferred stimulus-driven regulation of lateralized motor reactivity described by SIA, which was against the one expected on the basis of a valence-specific lateral bias, was entirely due to attentional capture from motivational significance (beyond numerical cognition). In order to establish the relevance of numerical cognition on the regulation of attentional capture we ran two complementary experiments. These involved the same direct comparison task on stimulus pairs that were fully comparable in terms of their analog representation of intensity but with different representational domain and motivational significance: symbolic magnitudes with low motivational significance in experiment 1 vs. emotions with rather high motivational significance in experiment 2. The results reveal a general SIA and point to a general mechanism regulating comparative judgements. This is based on the way spatial attention is captured toward locations that contain the stimulus which is closest in term of relative intensity to the extremal values of the series, regardless from its representational domain being it symbolic or emotional.


Assuntos
Cognição/fisiologia , Emoções/fisiologia , Julgamento/fisiologia , Conceitos Matemáticos , Navegação Espacial/fisiologia , Adulto , Atenção/fisiologia , Feminino , Humanos , Itália , Masculino , Estudantes , Universidades , Adulto Jovem
6.
Psychol Res ; 84(4): 950-965, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30511158

RESUMO

Both numerical and non-numerical magnitudes elicit similar Spatial-Numerical Association of Response Codes (SNARC) effects, with small magnitudes associated with left hand responses and large magnitudes associated with right hand responses (Dehaene et al., J Exp Psychol Gen 122(3), 371, 1993). In the present study, we investigated whether the phenomenal size of visual illusions elicits the same SNARC-like effect revealed for the physical size of pictorial surfaces. Four experiments were conducted by using the Delboeuf illusion (Experiment 1) and the Kanizsa triangle illusion (Experiments 2, 3 and 4). Experiment 1 suggests the presence of a SNARC-like compatibility effect for the physical size of the inducers, while this effect was not revealed for the phenomenal size of the induced elements, possibly masked by a stronger effect of the inducers. A SNARC-like effect for the phenomenal size of the Kanizsa triangle was revealed when participants directly compared the size of the triangles (Experiment 4). Conversely, when participants performed an indirect task (orientation judgment), the SNARC-like effect was present neither for the illusory nor for the physical displays (Experiments 2 and 3). The effect revealed for the size of illusory triangles was comparable to that of real triangles with physical contours, suggesting that both phenomenal and physical magnitudes similarly elicit SNARC-like effects.


Assuntos
Percepção de Forma , Ilusões/psicologia , Julgamento , Percepção Espacial , Feminino , Humanos , Masculino , Orientação , Estimulação Luminosa , Adulto Jovem
7.
Ann Hepatol ; 15(3): 410-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27049495

RESUMO

RATIONALE FOR THE STUDY: This cross-sectional multicenter study was conducted to investigate any difference in liver stiffness measurements (LSM), evaluated by transient elastography, between patients affected by ß thalassaemia major, with and without hepatitis C virus (HCV) infection, and healthy blood donors (controls). Secondary aim was to assess any correlation between transient elastography and serum ferritin, liver magnetic resonance imaging (MRI) T2* or superconductive quantum interference device (SQUID) liver susceptometry values. MATERIALS AND METHODS: The study involved three centers. Transient elastography and MRI T2* examinations were performed in all centers. SQUID liver susceptometry was performed in center1 and center2. T-test for independent data or Mann-Whitney U test was used to analyse differences between two groups. Univariate Pearson's r coefficient was used to test correlations between liver stiffness measurements and all other variables. RESULTS: In a study with 119 patients and 183 controls, patients who had never been infected with HCV showed significantly higher LSMs than controls [5.7 (95% CI, 5.2-6.2) kPa vs. 4.3 (95% CI, 4.1-4.4) kPa, p < 0.0001]. A moderate correlation between LSMs and ferritin values, adjusted for gender and age, was found in patients (r = 0.49, p < 0.0001) but not in controls (r = -0.22, p = 0.6). No correlation between LSMs and MRI T2* or SQUID liver susceptometry values was observed. In conclusion, compared to controls ß thalassaemia major patients had a significant increase in LSMs independently from HCV infection.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Hepatite C/complicações , Cirrose Hepática/patologia , Fígado/patologia , Ultrassonografia , Talassemia beta/complicações , Adulto , Estudos de Casos e Controles , Estudos Transversais , Elasticidade , Feminino , Hepatite C/diagnóstico , Humanos , Itália , Fígado/virologia , Cirrose Hepática/etiologia , Cirrose Hepática/virologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fatores de Risco , Adulto Jovem , Talassemia beta/diagnóstico
8.
Perception ; 45(9): 1060-9, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27251169

RESUMO

Pitch height and pitch class are different, but strictly related, percepts of music tones. To investigate the influence of pitch height in a pitch class identification task, we systematically analyzed the errors-in terms of direction and amount-committed by a group of musicians. The aim of our study was to verify the existence of constant errors in the identification of pitch classes across consecutive octaves. Stimuli were single piano tones from the C major scale executed in two consecutive octaves. Participants showed different response patterns in the two octaves. The direction of errors revealed a constant tendency to underestimate pitch classes in the lowest octave and to overestimate pitch classes in the highest octave. Thus, pitch height showed to influence pitch class identification. We called this bias "pitch class polarization", since the same pitch class was judged to be respectively lower and higher, depending on relatively low or high pitch height.


Assuntos
Percepção da Altura Sonora/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
9.
Psychol Res ; 80(1): 76-81, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25637249

RESUMO

Previous research has demonstrated that auditory rhythms affect both movement and physiological functions. We hypothesized that the ecological sounds of human breathing can affect breathing more than artificial sounds of breathing, varying in tones for inspiration and expiration. To address this question, we monitored the breath duration of participants exposed to three conditions: (a) ecological sounds of breathing, (b) artificial sounds of breathing having equal temporal features as the ecological sounds, (c) no sounds (control). We found that participants' breath duration variability was reduced in the ecological sound condition, more than in the artificial sound condition. We suggest that ecological sounds captured the timing of breathing better than artificial sounds, guiding as a consequence participants' breathing. We interpreted our results according to the Theory of Event Coding, providing further support to its validity, and suggesting its possible extension in the domain of physiological functions which are both consciously and unconsciously controlled.


Assuntos
Mecânica Respiratória/fisiologia , Sons Respiratórios/fisiologia , Adulto , Feminino , Humanos , Masculino , Movimento , Fatores de Tempo , Adulto Jovem
10.
Langmuir ; 30(39): 11591-8, 2014 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-25222857

RESUMO

The studies on surface chemical gradients are constantly gaining interest both for fundamental studies and for technological implications in materials science, nanofluidics, dewetting, and biological systems. Here we report on a new approach that is very simple and very efficient, to fabricate surface chemical gradients of alkanethiols, which combines electrochemical desorption/partial readsorption, with the withdrawal of the surface from the solution. The gradient is then stabilized by adding a complementary thiol terminated with a hydroxyl group with a chain length comparable to desorbed thiols. This procedure allows us to fabricate a chemical gradient of the wetting properties and the substrate work-function along a few centimeters with a gradient slope higher than 5°/cm. Samples were characterized by cyclic voltammetry during desorption, static contact angle, XPS analysis, and Kelvin probe. Computer simulations based on the Dissipative Particle Dynamics methods were carried out considering a water droplet on a mixed SAM surface. The results help to rationalize the composition of the chemical gradient at different position on the Au surface.


Assuntos
Compostos de Sulfidrila/química , Adsorção , Eletroquímica , Ouro/química , Modelos Moleculares , Conformação Molecular , Oxirredução , Propriedades de Superfície
11.
J Intell ; 12(2)2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38392171

RESUMO

Starting approximately from the beginning of the new millennium, a series of studies highlighted that auditory information deriving from biological motion can significantly influence the behavioral, cognitive and neurophysiological processes involved in the perception and execution of complex movements. In particular, it was observed that an appropriate use of sounds deriving from one's own movement promotes improvements in the movement execution itself. Two main approaches can be used, namely the sonification one or the ecological sound one; the former is based on the conversion of physiological and/or physical movement data into sound, while the latter is based on the use of auditory recordings of movement sounds as models. In the present article, some of the main applications of both approaches-especially the latter-to the domains of sport and motor rehabilitation are reviewed, with the aim of addressing two questions: Is it possible to consider rhythm as a Gestalt of human movement? If so, is it possible to build up cognitive strategies to improve/standardize movement performance from this Gestalt? As with most topics in science, a definitive answer is not possible, yet the evidence leads us to lean toward a positive answer to both questions.

12.
Atten Percept Psychophys ; 86(1): 263-272, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37985595

RESUMO

The Spatial-Numerical Association of Response Codes (SNARC) effect is evidence of an association between number magnitude and response position, with faster left-key responses to small numbers and faster right-key responses to large numbers. Similarly, recent studies revealed a SNARC-like effect for tempo, defined as the speed of an auditory sequence, with faster left-key responses to slow tempo and faster right-key responses to fast tempo. In order to address some methodological issues of previous studies, in the present study we designed an experiment to investigate the occurrence of a SNARC-like effect for tempo, employing a novel procedure in which only two auditory beats in sequence with a very short interstimulus interval were used. In the "temporal speed" condition, participants were required to judge the temporal speed (slow or fast) of the sequence. In the "interval duration" condition, participants were required to judge the duration of the interval between the two beats (short or long). The results revealed a consistent SNARC-like effect in both conditions, with faster left-hand responses to slow tempo and faster right-hand responses to fast tempo. Interestingly, the consistency of the results across the two conditions indicates that the direction of the SNARC-like effect was influenced by temporal speed even when participants were explicitly required to focus on interval duration. Overall, the current study extends previous findings by employing a new paradigm that addresses potential confounding factors and strengthens evidence for the SNARC-like effect for tempo.


Assuntos
Mãos , Percepção Espacial , Humanos , Tempo de Reação/fisiologia , Percepção Espacial/fisiologia , Mãos/fisiologia
13.
Phys Chem Chem Phys ; 15(11): 3897-905, 2013 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-23400105

RESUMO

Electronic transducers of neuronal cellular activity are important devices in neuroscience and neurology. Organic field-effect transistors (OFETs) offer tailored surface chemistry, mechanical flexibility, and high sensitivity to electrostatic potential changes at device interfaces. These properties make them attractive for interfacing electronics with neural cells and performing extracellular recordings and stimulation of neuronal network activity. In this work we operate pentacene ultra-thin film (9 nm thick) transistors with a liquid gate both as transducers and electrical stimulators of neuronal network activity. These devices are highly sensitive to small potential changes in cell medium and exhibit sufficient stability under standard cell culture conditions for nine days. We show that murine neural stem cells can be adhered on top of functional devices without the need for an additional layer of cell-adhesive molecules, and then differentiated into neuronal networks. OFET response is monitored during the different phases of the neuronal differentiation process up to nine days. Only when stem cells are differentiated into neurons, it is possible to measure electrical signals in the OFET current following the stimulation. Due to the large sensing area of our device, which accommodates from hundreds to thousands of interconnected neurons, the OFET electrical signals arise from the collective electrophysiological response of the neuronal population. The maximum extracellular potential change in the cleft region adjacent to the transistor surface amounts to 350 µV. This demonstrates that pentacene ultra-thin film OFETs enable good cellular adhesion and efficient coupling of the ionic currents at the biological-organic semiconductor interface with the OFET current.


Assuntos
Neurônios/metabolismo , Compostos Orgânicos/química , Células-Tronco/metabolismo , Transistores Eletrônicos , Animais , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Eletrodos , Camundongos , Neurônios/citologia , Células-Tronco/citologia
14.
Psychon Bull Rev ; 30(4): 1422-1430, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36650364

RESUMO

Both symbolic (digits) and non-symbolic (dots) numerals are spatially coded, with relatively small numbers being responded faster with a left key and large numbers being responded faster with a right key (spatial-numerical association of response codes [SNARC]). The idea of format independent SNARC seems to support the existence of a common system for symbolic and non-symbolic numerical representations, although evidence in the field is still mixed. The aim of the present study is to investigate whether symbolic and non-symbolic numerals interact in the SNARC effect when both information is simultaneously displayed. To do so, participants were presented with dice-like patterns, with digits being used instead of dots. In two separate magnitude classification tasks, participants had to respond either to the number of digits presented on the screen or to their numerical size. In the non-symbolic task, they had to judge whether the digits on the screen were more or less than three, irrespective of the numerical value of the digits. In the symbolic task, participants had to judge whether the digits on the screen were numerically smaller or larger than three, irrespective of the number of digits being present. The results show a consistent SNARC effect in the symbolic task and no effect in the non-symbolic one. Furthermore, congruency between symbolic and non-symbolic numerals did not modulate the response patterns, thus supporting the idea of independent representations and questioning some propositions of current theoretical accounts.


Assuntos
Percepção Espacial , Humanos , Percepção Espacial/fisiologia , Tempo de Reação/fisiologia
15.
Sci Rep ; 13(1): 7324, 2023 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-37147340

RESUMO

Humans are predisposed to attend to emotions conveyed by facial expressions. However, compulsory attraction to emotions gets challenging when multiple emotional stimuli compete for attention, as in the emotion comparison task. In this task, participants are asked to choose which of two simultaneously presented faces displays the most positive (happiest) or negative (angriest) emotion. Participants usually respond faster to the face displaying the most intense emotion. This effect is stronger for face pairs that contain globally positive rather than negative emotional faces. Both effects are consistent with an attentional capture phenomenon driven by the perceptual salience of facial expressions. In the present experiment, we studied the temporal dynamics of attentional capture in the emotion comparison task by tracking participants' eye movements using gaze-contingent displays and responses. Our results show that, on the first fixation, participants were more accurate and dwelled longer on the left target face when it displayed the most intense emotion within the pair. On the second fixation, the pattern was reversed, with higher accuracy and longer gaze time on the right target face. Overall, our pattern of gazing behavior indicates that the typical results observed in the emotion comparison task arise from the optimal combination over time of two low-level attentional factors: the perceptual salience of emotional stimuli and the scanning habit of participants.


Assuntos
Emoções , Movimentos Oculares , Humanos , Emoções/fisiologia , Ira , Felicidade , Expressão Facial
16.
Sci Rep ; 13(1): 5301, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37002375

RESUMO

The control and manipulation of superparamagnetic nanoparticles (SP-MNP) is a significant challenge and has become increasingly important in various fields, especially in biomedical research. Yet, most of applications rely on relatively large nanoparticles, 50 nm or higher, mainly due to the fact that the magnetic control of smaller MNPs is often hampered by the thermally induced Brownian motion. Here we present a magnetic device able to manipulate remotely in microfluidic environment SP-MNPs smaller than 10 nm. The device is based on a specifically tailored configuration of movable permanent magnets. The experiments performed in 500 µm capillary have shown the ability to concentrate the SP-MNPs into regions characterized by different shapes and sizes ranging from 100 to 200 µm. The results are explained by straightforward calculations and comparison between magnetic and thermal energies. We provide then a comprehensive description of the magnetic field intensity and its spatial distribution for the confinement and motion of magnetic nanoparticles for a wide range of sizes. We believe this description could be used to establish accurate and quantitative magnetic protocols not only for biomedical applications, but also for environment, food, security, and other areas.

17.
ACS Appl Mater Interfaces ; 15(51): 59224-59235, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38091494

RESUMO

Biomaterials able to promote neuronal development and neurite outgrowth are highly desired in neural tissue engineering for the repair of damaged or disrupted neural tissue and restoring the axonal connection. For this purpose, the use of either electroactive or micro- and nanostructured materials has been separately investigated. Here, the use of a nanomodulated conductive poly(3,4-ethylendioxithiophene) poly(styrenesulfonate) (PEDOT/PSS) substrate that exhibits instructive topographical and electrical cues at the same time was investigated for the first time. In particular, thin films featuring grooves with sizes comparable with those of neuronal neurites (NanoPEDOT) were fabricated by electrochemical polymerization of PEDOT/PSS on a nanomodulated polycarbonate template. The ability of NanoPEDOT to support neuronal development and direct neurite outgrowth was demonstrated by assessing cell viability and proliferation, expression of neuronal markers, average neurite length, and direction of neuroblastoma N2A cells induced to differentiate on this novel support. In addition to the beneficial effect of the nanogrooved topography, a 30% increase was shown in the average length of neurites when differentiating cells were subjected to an electrical stimulation of a few microamperes for 6 h. The results reported here suggest a favorable effect on the neuronal development of the synergistic combination of nanotopography and electrical stimulation, supporting the use of NanoPEDOT in neural tissue engineering to promote physical and functional reconnection of impaired neural networks.


Assuntos
Neurogênese , Neurônios , Materiais Biocompatíveis/farmacologia , Neuritos/metabolismo , Condutividade Elétrica
18.
Front Neurosci ; 17: 1256224, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38125403

RESUMO

Visual hallucinations are prevalent, potentially disabling symptoms of Parkinson's Disease. Multiple impairments in bottom-up sensory processing and top-down perceptual modulation are implicated in the pathophysiology of these phenomena. In healthy individuals, visual illusions are elicited by illusory figures through parametric manipulations of geometrical configurations, contrast, color, or spatial relationships between stimuli. These illusory percepts provide insight on the physiologic processes subserving conscious and unconscious perception. In this exploratory, cross-sectional, controlled study, perceptual performance on illusory figures was assessed on 11 PD patients with hallucinations, 10 non-hallucinating PD patients, and 10 age-matched healthy individuals. In order to characterize potential neural substrates of perceptual performances, patients' brain metabolic patterns on FDG PET were also analyzed. Illusions relying on attentional modulation and global perception were attenuated in PD patients without hallucinations. This pattern was no longer recognizable in hallucinating patients. Conversely, illusory effects normally counteracted by figure to background segregation and overlapping figures recognition were enhanced in PD patients with hallucinations. FDG PET findings further suggest that perceptual differences between PD patients might be linked to abnormal top-down perceptual modulation.

19.
PeerJ ; 10: e13681, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35811811

RESUMO

Background: Due to the unfortunate pandemic situation, the phenomena of home advantage and referee bias in sports have recently received a particular research attention, especially in association football. In this regard, several studies were conducted on the last portion of the 2019-20 season: the majority of them suggests a reduction-but not the elimination-of the two phenomena, with some exceptions in which no reduction was found or, at the other extreme, the phenomena were not observed at all. Methods: The continuation of the pandemic made it possible to replicate the previous studies considering the complete 2020-21 season, thus with the important added value of having a fully balanced home/away schedule-and a higher number of matches-in the various leagues. In particular, the sample of the present study consisted of 3,898 matches from the first and second divisions of the UEFA top five ranked countries, that is, England, Spain, Italy, Germany, and France. For the home advantage, the following variables were examined: distribution of matches outcomes and home advantage for points (also for previous seasons from the 2014-15 one); ball possession; total shots; shots on goal; and corner kicks. Instead, for he referee bias, the following variables were examined: fouls; yellow cards; red cards; penalty kicks; and extra time. Chi-square tests were used to compare the distribution of matches outcomes, and t-tests to compare home vs. away data for the other variables in the 2020-21 season; Bayesian and equivalence analyses were also conducted. Results: The main results are as follows: (a) the distribution of matches outcomes in the 2020-21 season was significantly different from that of the last five complete seasons with spectators (Chi-square = 37.42, df = 2, p < 0.001), with fewer home victories and more away victories; the resulting values of the home advantage for points were 54.95% for the 2020-21 season, and 59.36% for the previous seasons; (b) for the other home advantage variables, a statistically significant overall advantage for the home team emerged; nevertheless, the strength of the differences between home and away teams was generally small (0.09 < Cohen's d < 0.17), and the corresponding means can be considered statistically equivalent for all variables but the total shots; (c) no statistically significant differences emerged between home and away teams for any of the referee bias variables. Discussion: These findings demonstrate that the absence of spectators significantly reduced the home advantage compared to previous seasons with spectators. A slight home advantage persisted in the 2020-21 season, probably due to other factors, namely, learning and travel, according to the model by Courneya & Carron (1992). Conversely, the referee bias was not observed, suggesting that it mainly derives from the pressure normally exerted by spectators.


Assuntos
Futebol , Humanos , Masculino , Alemanha , Estações do Ano
20.
Sci Rep ; 12(1): 18822, 2022 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-36335159

RESUMO

The Spatial-TEmporal Association of Response Codes (STEARC) effect (Ishihara et al. in Cortex 44:454-461, 2008) is evidence that time is spatially coded along the horizontal axis. It consists in faster left-hand responses to early onset timing and faster right-hand responses to late onset timing. This effect has only been established using tasks that directly required to assess onset timing, while no studies investigated whether this association occurs automatically in the auditory modality. The current study investigated the occurrence of the STEARC effect by using a procedure similar to Ishihara and colleagues. Experiment 1 was a conceptual replication of the original study, in which participants directly discriminated the onset timing (early vs. late) of a target sound after listening to a sequence of auditory clicks. This experiment successfully replicated the STEARC effect and revealed that the onset timing is mapped categorically. In Experiments 2, 3a and 3b participants were asked to discriminate the timbre of the stimuli instead of directly assessing the onset timing. In these experiments, no STEARC effect was observed. This suggests that the auditory STEARC effect is only elicited when time is explicitly processed, thus questioning the automaticity of this phenomenon.


Assuntos
Percepção do Tempo , Humanos , Tempo de Reação/fisiologia , Percepção do Tempo/fisiologia , Percepção Auditiva/fisiologia , Estimulação Acústica
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