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2.
R Soc Open Sci ; 11(7): 240125, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39050728

RESUMO

Many-analysts studies explore how well an empirical claim withstands plausible alternative analyses of the same dataset by multiple, independent analysis teams. Conclusions from these studies typically rely on a single outcome metric (e.g. effect size) provided by each analysis team. Although informative about the range of plausible effects in a dataset, a single effect size from each team does not provide a complete, nuanced understanding of how analysis choices are related to the outcome. We used the Delphi consensus technique with input from 37 experts to develop an 18-item subjective evidence evaluation survey (SEES) to evaluate how each analysis team views the methodological appropriateness of the research design and the strength of evidence for the hypothesis. We illustrate the usefulness of the SEES in providing richer evidence assessment with pilot data from a previous many-analysts study.

3.
Prog Neurobiol ; 234: 102576, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38309459

RESUMO

The visual system represents objects in a lateralized manner, with contralateral cortical hemispheres responsible for left and right visual hemifields. This organization extends to visual short-term memory (VSTM), as evidenced by electrophysiological indices of VSTM maintenance: contralateral delay activity (CDA) and alpha-band lateralization. However, it remains unclear if VSTM represents object locations in gaze-centered (retinotopic) or screen-centered (spatiotopic) coordinates, especially after eye movements. In two experiments, participants encoded the colors of target objects and made a lateral saccade during the maintenance interval, thereby shifting the object's location on the retina. A non-lateralized probe stimulus was then presented at the new fixation for a change detection task. The CDA maintained lateralization towards the target's original retinotopic location, unaffected by subsequent saccades, and did not invert polarity even when a saccade brought that location into the opposite hemifield. We also found conventional alpha lateralization towards the target's location before a saccade. After a saccade, however, alpha was lateralized towards the screen center regardless of the target's original location, even in a control condition without any memory requirements. This suggests that post-saccadic alpha-band lateralization reflects attentional processes unrelated to memory, while pre- and post-saccade CDA reflect VSTM maintenance in a retinotopic reference frame.


Assuntos
Movimentos Oculares , Movimentos Sacádicos , Humanos , Memória de Curto Prazo/fisiologia , Atenção/fisiologia , Retina
4.
Int J Psychophysiol ; 198: 112312, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38336163

RESUMO

Fluctuations in sex steroid levels during the menstrual cycle and the use of hormonal contraceptives have been linked to changes in cognitive function and emotions in females. Such variations may be mediated by overall brain activity and excitability. We aimed to investigate the impact of female hormonal status on resting state EEG (rsEEG) parameters, including periodic (individual alpha frequency, alpha power) and aperiodic (1/f slope) features. rsEEG was recorded in healthy females (mean age 26.4 ± 4.6 years), who were naturally cycling in the early follicular (n = 33) or mid-luteal phases (n = 35), or who used either oral contraceptives (n = 35) or hormonal intrauterine devices (n = 28). Salivary concentrations of estradiol, progesterone, and testosterone were measured. Contrary to previous findings, this study did not reveal significant differences in rsEEG parameters between groups or significant relationships with hormonal levels. Age emerged as a covariate negatively related to the median 1/f slope. Based on these findings, we found no significant evidence to suggest that the periodic (alpha power and peak frequency) or aperiodic activity patterns in the brain during the resting state differ between the groups of females under investigation.


Assuntos
Ciclo Menstrual , Progesterona , Feminino , Humanos , Adulto Jovem , Adulto , Ciclo Menstrual/fisiologia , Estradiol , Encéfalo/fisiologia , Eletroencefalografia
5.
Artigo em Inglês | MEDLINE | ID: mdl-38177944

RESUMO

Hypothesis-driven research rests on clearly articulated scientific theories. The building blocks for communicating these theories are scientific terms. Obviously, communication - and thus, scientific progress - is hampered if the meaning of these terms varies idiosyncratically across (sub)fields and even across individual researchers within the same subfield. We have formed an international group of experts representing various theoretical stances with the goal to homogenize the use of the terms that are most relevant to fundamental research on visual distraction in visual search. Our discussions revealed striking heterogeneity and we had to invest much time and effort to increase our mutual understanding of each other's use of central terms, which turned out to be strongly related to our respective theoretical positions. We present the outcomes of these discussions in a glossary and provide some context in several essays. Specifically, we explicate how central terms are used in the distraction literature and consensually sharpen their definitions in order to enable communication across theoretical standpoints. Where applicable, we also explain how the respective constructs can be measured. We believe that this novel type of adversarial collaboration can serve as a model for other fields of psychological research that strive to build a solid groundwork for theorizing and communicating by establishing a common language. For the field of visual distraction, the present paper should facilitate communication across theoretical standpoints and may serve as an introduction and reference text for newcomers.

6.
eNeuro ; 11(2)2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38164570

RESUMO

We explore the world by constantly shifting our focus of attention toward salient stimuli and then disengaging from them in search of new ones. The alpha rhythm (8-13 Hz) has been suggested as a pivotal neural substrate of these attentional shifts, due to its local synchronization and desynchronization that suppress irrelevant cortical areas and facilitate relevant areas, a phenomenon called alpha lateralization. Whether alpha lateralization tracks the focus of attention from orienting toward a salient stimulus to disengaging from it is still an open question. We addressed it by leveraging the phenomenon of inhibition of return (IOR), consisting of an initial facilitation in response times (RTs) for stimuli appearing at an exogenously cued location, followed by a suppression of that location. Our behavioral data from human participants showed a typical IOR effect with both early facilitation and subsequent inhibition. In contrast, alpha lateralized in the cued direction after the behavioral facilitation effect and never re-lateralized compatibly with the behavioral inhibition. Furthermore, we analyzed the interaction between alpha lateralization and microsaccades: while alpha was lateralized toward the cued location, microsaccades were mostly oriented away from it. Crucially, the two phenomena showed a significant positive correlation. These results indicate that alpha lateralization reflects primarily the processing of salient stimuli, challenging the view that alpha lateralization is directly involved in exogenous attentional orienting per se. We discuss the relevance of the present findings for an oculomotor account of alpha lateralization as a modulator of cortical excitability in preparation of a saccade.


Assuntos
Sinais (Psicologia) , Inibição Psicológica , Humanos , Tempo de Reação/fisiologia , Movimentos Sacádicos , Movimentos Oculares
7.
J Cogn Neurosci ; 36(2): 217-224, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38010291

RESUMO

The ongoing reproducibility crisis in psychology and cognitive neuroscience has sparked increasing calls to re-evaluate and reshape scientific culture and practices. Heeding those calls, we have recently launched the EEGManyPipelines project as a means to assess the robustness of EEG research in naturalistic conditions and experiment with an alternative model of conducting scientific research. One hundred sixty-eight analyst teams, encompassing 396 individual researchers from 37 countries, independently analyzed the same unpublished, representative EEG data set to test the same set of predefined hypotheses and then provided their analysis pipelines and reported outcomes. Here, we lay out how large-scale scientific projects can be set up in a grassroots, community-driven manner without a central organizing laboratory. We explain our recruitment strategy, our guidance for analysts, the eventual outputs of this project, and how it might have a lasting impact on the field.


Assuntos
Eletroencefalografia , Projetos de Pesquisa , Humanos , Reprodutibilidade dos Testes
8.
Atten Percept Psychophys ; 85(6): 2111-2121, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37610529

RESUMO

When exogenously cued, attention reflexively reorients towards the cued position. After a brief dwelling time, attention is released and then persistently inhibited from returning to this position for up to three seconds, a phenomenon coined 'inhibition of return' (IOR). This inhibitory interpretation has shaped our understanding of the spatio-temporal dynamics of the attentional spotlight after an exogenous visual cue for more than three decades. However, a recent theory refines this traditional view and predicts that attention rhythmically alternates between possible target locations at a theta frequency, implying occasional returns of attention to the cued position. Unfortunately, previous IOR studies have only probed performance at a few, temporally wide-spread cue-target onset asynchronies (CTOAs) rendering a comparison of these contradictory predictions impossible. We therefore used a temporally fine-grained adaptation of the Posner paradigm with 25 equally and densely spaced CTOAs, which yielded a robust IOR effect in the reaction time difference between valid and invalidly cued trials. We modelled the time course of this effect across CTOAs as a linear or exponential decay (traditional IOR model), sinusoidal rhythm (rhythmic model) and a combination of both (hybrid model). Model comparison by means of goodness-of-fit indices provided strong evidence in favor of traditional IOR models, and against theta-rhythmic attentional sampling contributing to IOR. This finding was supported by an FFT analysis, which also revealed no significant theta rhythm. We therefore conclude that the spatio-temporal dynamics of attention following an exogenous cue cannot be explained by rhythmic attentional sampling.


Assuntos
Sinais (Psicologia) , Inibição Psicológica , Humanos , Tempo de Reação/fisiologia
9.
Chem Senses ; 482023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37350646

RESUMO

People often confuse smell loss with taste loss, so it is unclear how much gustatory function is reduced in patients self-reporting taste loss. Our pre-registered cross-sectional study design included an online survey in 12 languages with instructions for self-administering chemosensory tests with 10 household items. Between June 2020 and March 2021, 10,953 individuals participated. Of these, 5,225 self-reported a respiratory illness and were grouped based on their reported COVID test results: COVID-positive (COVID+, N = 3,356), COVID-negative (COVID-, N = 602), and COVID unknown for those waiting for a test result (COVID?, N = 1,267). The participants who reported no respiratory illness were grouped by symptoms: sudden smell/taste changes (STC, N = 4,445), other symptoms excluding smell or taste changes (OthS, N = 832), and no symptoms (NoS, N = 416). Taste, smell, and oral irritation intensities and self-assessed abilities were rated on visual analog scales. Compared to the NoS group, COVID+ was associated with a 21% reduction in taste (95% confidence interval (CI): 15-28%), 47% in smell (95% CI: 37-56%), and 17% in oral irritation (95% CI: 10-25%) intensity. There were medium to strong correlations between perceived intensities and self-reported abilities (r = 0.84 for smell, r = 0.68 for taste, and r = 0.37 for oral irritation). Our study demonstrates that COVID-19-positive individuals report taste dysfunction when self-tested with stimuli that have little to none olfactory components. Assessing the smell and taste intensity of household items is a promising, cost-effective screening tool that complements self-reports and may help to disentangle taste loss from smell loss. However, it does not replace standardized validated psychophysical tests.


Assuntos
Ageusia , COVID-19 , Transtornos do Olfato , Humanos , COVID-19/diagnóstico , Olfato , Paladar , Anosmia , SARS-CoV-2 , Estudos Transversais , Transtornos do Olfato/diagnóstico , Distúrbios do Paladar/diagnóstico
10.
Atten Percept Psychophys ; 85(3): 718-733, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36917354

RESUMO

Working memory is inherently limited, which makes it important to select and maintain only task-relevant information and to protect it from distraction. Previous research has suggested the contralateral delay activity (CDA) and lateralized alpha oscillations as neural candidates for such a prioritization process. While most of this work focused on distraction during encoding, we examined the effect of external distraction presented during memory maintenance. Participants memorized the orientations of three lateralized objects. After an initial distraction-free maintenance interval, distractors appeared in the same location as the targets or in the opposite hemifield. This distraction was followed by another distraction-free interval. Our results show that CDA amplitudes were stronger in the interval before compared with the interval after the distraction (i.e., CDA amplitudes were stronger in response to targets compared with distractors). This amplitude reduction in response to distractors was more pronounced in participants with higher memory accuracy, indicating prioritization and maintenance of relevant over irrelevant information. In contrast, alpha lateralization did not change from the interval before distraction compared with the interval after distraction, and we found no correlation between alpha lateralization and memory accuracy. These results suggest that alpha lateralization plays no direct role in either selective maintenance of task-relevant information or inhibition of distractors. Instead, alpha lateralization reflects the current allocation of spatial attention to the most salient information regardless of task-relevance. In contrast, CDA indicates flexible allocation of working memory resources depending on task-relevance.


Assuntos
Memória de Curto Prazo , Percepção Visual , Humanos , Memória de Curto Prazo/fisiologia , Percepção Visual/fisiologia , Eletroencefalografia/métodos , Estimulação Luminosa/métodos , Inibição Psicológica
11.
medRxiv ; 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36711499

RESUMO

People often confuse smell loss with taste loss, so it is unclear how much gustatory function is reduced in patients self-reporting taste loss. Our pre-registered cross-sectional study design included an online survey in 12 languages with instructions for self-administering chemosensory tests with ten household items. Between June 2020 and March 2021, 10,953 individuals participated. Of these, 3,356 self-reported a positive and 602 a negative COVID-19 diagnosis (COVID+ and COVID-, respectively); 1,267 were awaiting test results (COVID?). The rest reported no respiratory illness and were grouped by symptoms: sudden smell/taste changes (STC, N=4,445), other symptoms excluding smell or taste loss (OthS, N=832), and no symptoms (NoS, N=416). Taste, smell, and oral irritation intensities and self-assessed abilities were rated on visual analog scales. Compared to the NoS group, COVID+ was associated with a 21% reduction in taste (95% Confidence Interval (CI): 15-28%), 47% in smell (95%-CI: 37-56%), and 17% in oral irritation (95%-CI: 10-25%) intensity. In all groups, perceived intensity of smell (r=0.84), taste (r=0.68), and oral irritation (r=0.37) was correlated. Our findings suggest most reports of taste dysfunction with COVID-19 were genuine and not due to misinterpreting smell loss as taste loss (i.e., a classical taste-flavor confusion). Assessing smell and taste intensity of household items is a promising, cost-effective screening tool that complements self-reports and helps to disentangle taste loss from smell loss. However, it does not replace standardized validated psychophysical tests.

12.
Emotion ; 23(6): 1687-1701, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36395025

RESUMO

For humans, it is vitally important to rapidly detect potentially threatening stimuli such as fearful faces in the periphery. Trait anxiety has been related to biased responses to threatening faces, which might be more pronounced for peripheral stimuli. We examined the impact of spatial location and trait anxiety on event-related potentials to fearful faces (ERPs) in a large sample (N = 80). Using a face-unrelated oddball detection task and online eye-tracking, we ensured central fixation but sustained attention to the location of fearful and neutral faces at central or peripheral locations (12° left or right). Manipulation checks showed high task performance and successful shifts of visuospatial attention indexed by prestimulus alpha lateralization of the EEG spectra. Concerning ERPs, we observed increased P1 amplitudes for fearful compared to neutral faces, independent of the spatial location. In contrast, the N170 to fearful faces was only potentiated for centrally presented faces. Finally, fearful and neutral faces did not differ during the EPN window at any spatial location. Trait anxiety was unrelated to fearful-neutral ERP differences for each examined location. Our findings show that differential P1 responses are less constrained by the stimulus location, possibly due to coarse low-level stimulus information processing. However, the relative N170 increase for fearful faces depends on the central stimulus location. Furthermore, findings support the view that differential processing at the stage of the EPN depends on attentional conditions. Finally, our results question the hypothesis that trait anxiety differences correlate with mandatorily altered processing of threatening stimuli. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Ansiedade , Eletroencefalografia , Humanos , Eletroencefalografia/métodos , Medo/fisiologia , Potenciais Evocados/fisiologia , Transtornos de Ansiedade , Expressão Facial
13.
Psychophysiology ; 60(4): e14215, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36331158

RESUMO

For humans, it is vitally important to rapidly detect and process threatening signals regardless of whether stimuli occur at fixation or in the periphery. However, it is unknown whether eccentricity affects early neuronal electrophysiological responses to fear-conditioned stimuli. We examined early event-related potentials (ERPs) of the electroencephalogram (EEG) to fear-conditioned faces to address this question. Participants (N = 80) were presented with faces, either paired with an aversive (CS+) or neutral sound (CS-), at central or peripheral positions. We ensured constant central fixation using online eye-tracking but directed attention to either centrally or peripherally presented faces. Manipulation checks showed successful fear-conditioning (i.e., on average lower ratings in valence and higher ratings in arousal and perceived threat) and successful shifts of visuospatial attention indexed by high task performance and pre-stimulus alpha lateralization of the EEG spectra. We observed a generally increased P1 to fear-conditioned faces regardless of presentation location. An N170 difference between fear-conditioned and neutral stimuli was found but was restricted to the central location and depended on the effectivity of fear-conditioning. A similar effect was observed for the early posterior negativity (EPN). Trait anxiety was not related to differential ERP responses to CS+ versus CS- faces for any ERP component. These findings suggest that the P1 indexes early responses to centrally and peripherally presented fear-conditioned faces. Subsequent stages are modulated by the spatial location of the stimuli. This suggests different stages of neural processing of fear-conditioned faces depending on their spatial location. Finally, our results question the hypothesis that trait anxiety in healthy participants is related to altered visual processing of fear-conditioned faces.


Assuntos
Ansiedade , Medo , Humanos , Medo/fisiologia , Eletroencefalografia , Potenciais Evocados/fisiologia , Transtornos de Ansiedade , Expressão Facial
14.
J Vis ; 22(11): 9, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36227616

RESUMO

Our visual memories of complex scenes often appear as robust, detailed records of the past. Several studies have demonstrated that active exploration with eye movements improves recognition memory for scenes, but it is unclear whether this improvement is due to stronger feelings of familiarity or more detailed recollection. We related the extent and specificity of fixation patterns at encoding and retrieval to different recognition decisions in an incidental memory paradigm. After incidental encoding of 240 real-world scene photographs, participants (N = 44) answered a surprise memory test by reporting whether an image was new, remembered (indicating recollection), or just known to be old (indicating familiarity). To assess the specificity of their visual memories, we devised a novel report procedure in which participants selected the scene region that they specifically recollected, that appeared most familiar, or that was particularly new to them. At encoding, when considering the entire scene,subsequently recollected compared to familiar or forgotten scenes showed a larger number of fixations that were more broadly distributed, suggesting that more extensive visual exploration determines stronger and more detailed memories. However, when considering only the memory-relevant image areas, fixations were more dense and more clustered for subsequently recollected compared to subsequently familiar scenes. At retrieval, the extent of visual exploration was more restricted for recollected compared to new or forgotten scenes, with a smaller number of fixations. Importantly, fixation density and clustering was greater in memory-relevant areas for recollected versus familiar or falsely recognized images. Our findings suggest that more extensive visual exploration across the entire scene, with a subset of more focal and dense fixations in specific image areas, leads to increased potential for recollecting specific image aspects.


Assuntos
Rememoração Mental , Reconhecimento Psicológico , Movimentos Oculares , Humanos , Memória , Estimulação Luminosa
16.
Psychophysiology ; 59(11): e14114, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35652518

RESUMO

There is an ongoing debate on how different components of the event-related potential (ERP) to threat-related facial expressions are modulated by attentional conditions and interindividual differences in trait anxiety. In the current study (N = 80), we examined ERPs to centrally presented, task-irrelevant fearful and neutral faces, while participants had to solve a face-unrelated visual task, which differed in difficulty and spatial position. Critically, we used a fixation-controlled experimental design and ensured the spatial attention manipulation by spectral analysis of the EEG. Besides the factors emotion, spatial attention, and perceptual load, we also investigated correlations between trait anxiety and ERPs. While P1 emotion effects were insignificant, the N170 was increased to fearful faces regardless of load and spatial attention conditions. During the EPN time window, a significantly increased negativity for fearful faces was observed only during low load and spatial attention to the face. We found no significant relationship between ERPs and trait anxiety, questioning the hypothesis of a general hypersensitivity toward fearful expressions in anxious individuals. These results show a high resistance of the N170 amplitude increase for fearful faces to spatial attention and task load manipulations. By contrast, the EPN modulation by fearful faces index a resource-dependent stage of the ERP, requiring both spatial attention at the location of faces and low load of the face-irrelevant task.


Assuntos
Eletroencefalografia , Expressão Facial , Ansiedade/psicologia , Eletroencefalografia/métodos , Emoções/fisiologia , Potenciais Evocados/fisiologia , Medo/psicologia , Humanos
17.
J Neurophysiol ; 127(6): 1655-1668, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35647737

RESUMO

Eyeblinks are the brief closures of the lid. They are accompanied by a cocontraction of the eye muscles that temporarily pulls the whole eyeball back into its socket. When blinks occur together with execution of saccadic gaze shifts, they interfere with the saccadic premotor circuit, causing these within-blink saccades to be slower than normal and also time-locked to blinks. To analyze the trajectory of within-blink saccades, subtraction of the entangled blink-related eye movement is required. Here we propose a combination of principal component analysis (PCA) and a regression model to subtract the blink-related component of the eye movement based on the respective blink metrics. We used electrooculography (EOG) to measure eye and lid movements of 12 participants who performed saccades with and without blinks. We found that within-blink saccades are slower than without-blink saccades and are tightly coupled in time to blink onset. Surprisingly, in some participants we observed large dynamic overshoots of up to 15° for saccades of only 5° amplitude. The finding of dynamic overshoots was independently confirmed by dynamic MRI for two of the participants and challenges the current view that within-blink saccades are programmed as slow, but straight, saccades. We hypothesize that the dynamic overshoots could be attributed to inhibition of omnipause neurons during blinks, the simultaneous cocontraction of extraocular muscles, or a combination of both.NEW & NOTEWORTHY This study observed that people make large dynamic overshoots when making a saccadic eye movement within a blink but their eyes are back on target by the time the eyelids are open. We used electrooculography (EOG) to measure eye movements even when the lid is down and introduced a novel procedure to subtract blink-related EOG components. These findings challenge the current view that within-blink saccades are programmed as slow but straight saccades.


Assuntos
Piscadela , Movimentos Sacádicos , Fenômenos Biomecânicos , Eletroculografia , Movimentos Oculares , Humanos
18.
Sci Data ; 9(1): 325, 2022 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-35715429

RESUMO

This dataset consists of raw 64-channel EEG, cardiovascular (electrocardiography and photoplethysmography), and pupillometry data from 86 human participants recorded during 4 minutes of eyes-closed resting and during performance of a classic working memory task - digit span task with serial recall. The participants either memorized or just listened to sequences of 5, 9, or 13 digits presented auditorily every 2 seconds. The dataset can be used for (1) developing algorithms for cognitive load discrimination and detection of cognitive overload; (2) studying neural (event-related potentials and brain oscillations) and peripheral (electrocardiography, photoplethysmography, and pupillometry) physiological signals during encoding and maintenance of each sequentially presented memory item; (3) correlating cognitive load and individual differences in working memory to neural and peripheral physiology, and studying the relationship between the physiological signals; (4) integration of the physiological findings with the vast knowledge coming from behavioral studies of verbal working memory in simple span paradigms. The data are shared in Brain Imaging Data Structure (BIDS) format and freely available on OpenNeuro ( https://openneuro.org/datasets/ds003838 ).


Assuntos
Encéfalo , Eletroencefalografia , Memória de Curto Prazo , Encéfalo/fisiologia , Potenciais Evocados/fisiologia , Humanos , Memória de Curto Prazo/fisiologia , Rememoração Mental
19.
J Neurosci ; 2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35589392

RESUMO

Perceptual decisions depend both on the features of the incoming stimulus and on the ongoing brain activity at the moment the stimulus is received. Specifically, trial-to-trial fluctuations in cortical excitability have been linked to fluctuations in the amplitude of prestimulus α oscillations (∼8-13 Hz), which are in turn are associated with fluctuations in subjects' tendency to report the detection of a stimulus. It is currently unknown whether α oscillations bias postperceptual decision-making, or even bias subjective perception itself. To answer this question, we used a contrast discrimination task in which both male and female human subjects reported which of two gratings (one in each hemifield) was perceived as having a stronger contrast. Our EEG analysis showed that subjective contrast was reduced for the stimulus in the hemifield represented in the hemisphere with relatively stronger prestimulus α amplitude, reflecting reduced cortical excitability. Furthermore, the strength of this spontaneous hemispheric lateralization was strongly correlated with the magnitude of individual subjects' biases, suggesting that the spontaneous patterns of α lateralization play a role in explaining the intersubject variability in contrast perception. These results indicate that spontaneous fluctuations in cortical excitability, indicated by patterns of prestimulus α amplitude, affect perceptual decisions by altering the phenomenological perception of the visual world.Significance Statement:Our moment-to-moment perception of the world is shaped by the features of the environment surrounding us, as much as by the constantly evolving states that characterize our brain activity. Previous research showed how the ongoing electrical activity of the brain can influence whether a stimulus has accessed conscious perception. However, evidence is currently missing on whether these electrical brain states can be associated to the subjective experience of a sensory input. Here we show that local changes in patterns of electrical brain activity preceding visual stimulation can bias our phenomenological perception. Importantly, we show that the strength of these variations can help explain the great interindividual variability in how we perceive the visual environment surrounding us.

20.
Nutrients ; 14(6)2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35334798

RESUMO

Taste and smell function decline with age, with robust impairment in the very old. Much less is known about taste and smell function in young and middle aged. We investigated taste and smell sensitivity via thresholds in a sub-sample of the NutriAct Family Study (NFS), the NFS Examinations cohort (NFSE; N = 251, age M = 62.5 years). We examined different aspects relating to taste and smell function: the degree to which taste and smell sensitivity relate to another and to taste and smell preferences, the role of gender and age, as well as effects on Quality of Life (QoL). Taste thresholds were highly correlated, but no correlation was observed between taste and smell thresholds and between thresholds and preference. Women were more sensitive for both taste and smell than men. We found no effect of age on sensitivity and no effect of sensitivity on QoL. All null findings were complemented by Bayesian statistics. Together our results indicate the independence of taste and smell despite their overlap during sensorial experiences. We found no evidence for age-related sensory decline, which could be due to our sample's characteristics of non-clinical volunteers with good dental health and 93% non-smokers.


Assuntos
Envelhecimento Saudável , Qualidade de Vida , Teorema de Bayes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Olfato , Paladar
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