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1.
Public Health ; 234: 217-223, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39089174

RESUMO

OBJECTIVES: The obesity prevalence in South Korea in 2021 stood at 38.4%. South Korea faces unique challenges in providing essential and emergency guidelines for weight management because of stepping into an aging society. We aimed to determine the daily diet patterns among the general Korean population and to investigate the association between such patterns and different obesity. STUDY DESIGN: Longitudinal prospective cohort study. METHODS: A total of 6539 adult participants (mean age 50.8 years, 52.9% male) with normal-weight adults were included from the Ansan-Ansung cohort of 10,030 Korean adults aged 40 or older and followed for an average of 11 years. Obesity was defined according to the criteria from the Korean Society for The Study of Obesity. Baseline dietary intake was assessed using a validated 103-item food frequency questionnaire. Dietary patterns were derived from k-means cluster analysis. RESULTS: In the multivariate analysis, referring to white rice + baechu kimchi, participants from multigrain rice + baechu kimchi showed lower HR for obesity development (waist circumference defined-obesity; HR: 0.87, 95% CI: 0.79, 0.95; body fat percentage defined-obesity; HR: 0.89, 95% CI: 0.80, 0.98). Further analysis documented that except for body fat percentage defined-obesity, consuming milk or dairy products was linked to a reduced incidence of the other three obesity (body mass index defined-obesity; HR: 0.84, 95% CI: 0.72, 0.99; waist circumference defined-obesity; HR: 0.82, 95% CI: 0.71, 0.94; waist-to-hip ratio defined-obesity; HR: 0.75, 95% CI: 0.61, 0.91). CONCLUSIONS: Following a diet that includes multigrain rice, fermented baechu kimchi, and dairy products is linked to a decreased risk of obesity in Korean adults. Public health programs and policies could incorporate these dietary recommendations, targeting specific population groups such as schoolchildren, adults, and the elderly. Additionally, further research is needed to explore the synergistic effects of various foods and their interactions within dietary patterns on obesity outcomes.

2.
Front Med (Lausanne) ; 11: 1412592, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39099597

RESUMO

Alzheimer's disease (AD) is a devastating brain disorder that steadily worsens over time. It is marked by a relentless decline in memory and cognitive abilities. As the disease progresses, it leads to a significant loss of mental function. Early detection of AD is essential to starting treatments that can mitigate the progression of this disease and enhance patients' quality of life. This study aims to observe AD's brain functional connectivity pattern to extract essential patterns through multivariate pattern analysis (MVPA) and analyze activity patterns across multiple brain voxels. The optimized feature extraction techniques are used to obtain the important features for performing the training on the models using several hybrid machine learning classifiers for performing binary classification and multi-class classification. The proposed approach using hybrid machine learning classification has been applied to two public datasets named the Open Access Series of Imaging Studies (OASIS) and the AD Neuroimaging Initiative (ADNI). The results are evaluated using performance metrics, and comparisons have been made to differentiate between different stages of AD using visualization tools.

3.
Hum Brain Mapp ; 45(10): e26726, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38949487

RESUMO

Resting-state functional connectivity (FC) is widely used in multivariate pattern analysis of functional magnetic resonance imaging (fMRI), including identifying the locations of putative brain functional borders, predicting individual phenotypes, and diagnosing clinical mental diseases. However, limited attention has been paid to the analysis of functional interactions from a frequency perspective. In this study, by contrasting coherence-based and correlation-based FC with two machine learning tasks, we observed that measuring FC in the frequency domain helped to identify finer functional subregions and achieve better pattern discrimination capability relative to the temporal correlation. This study has proven the feasibility of coherence in the analysis of fMRI, and the results indicate that modeling functional interactions in the frequency domain may provide richer information than that in the time domain, which may provide a new perspective on the analysis of functional neuroimaging.


Assuntos
Conectoma , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Conectoma/métodos , Adulto , Masculino , Feminino , Aprendizado de Máquina , Adulto Jovem , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiologia
4.
Cereb Cortex ; 34(7)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-39073379

RESUMO

Self-defining memories are highly significant personal memories that contribute to an individual's life story and identity. Previous research has identified 4 key subcomponents of self-defining memories: content, affect, specificity, and self-reflection. However, these components were not tested under functional neuroimaging. In this study, we first explored how self-defining memories distinguish themselves from everyday memories (non-self-defining) through their associated brain activity. Next, we evaluated the different self-defining memory subcomponents through their activity in the underlying brain system. Participants recalled both self-defining and non-self-defining memories under functional MRI and evaluated the 4 subcomponents for each memory. Multivoxel pattern analysis uncovered a brain system closely related to the default mode network to discriminate between self-defining and non-self-defining memories. Representational similarity analysis revealed the neural coding of each subcomponent. Self-reflection was coded mainly in the precuneus, middle and inferior frontal gyri, and cingulate, lateral occipital, and insular cortices. To a much lesser extent, content coding was primarily in the left angular gyrus and fusiform gyrus. No region was found to represent information on affect and specificity. Our findings highlight the marked difference in brain processing between significant and non-significant memories, and underscore self-reflection as a predominant factor in the formation and maintenance of self-defining memories, inviting a reassessment of what constitutes significant memories.


Assuntos
Mapeamento Encefálico , Encéfalo , Imageamento por Ressonância Magnética , Autoimagem , Humanos , Feminino , Masculino , Adulto Jovem , Adulto , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Rememoração Mental/fisiologia , Memória Episódica , Memória/fisiologia
5.
Neurosci Biobehav Rev ; 164: 105795, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38977116

RESUMO

Multivariate pattern analysis (MVPA) of electroencephalographic (EEG) data represents a revolutionary approach to investigate how the brain encodes information. By considering complex interactions among spatio-temporal features at the individual level, MVPA overcomes the limitations of univariate techniques, which often fail to account for the significant inter- and intra-individual neural variability. This is particularly relevant when studying clinical populations, and therefore MVPA of EEG data has recently started to be employed as a tool to study cognition in brain disorders. Here, we review the insights offered by this methodology in the study of anomalous patterns of neural activity in conditions such as autism, ADHD, schizophrenia, dyslexia, neurological and neurodegenerative disorders, within different cognitive domains (perception, attention, memory, consciousness). Despite potential drawbacks that should be attentively addressed, these studies reveal a peculiar sensitivity of MVPA in unveiling dysfunctional and compensatory neurocognitive dynamics of information processing, which often remain blind to traditional univariate approaches. Such higher sensitivity in characterizing individual neurocognitive profiles can provide unique opportunities to optimise assessment and promote personalised interventions.

6.
Neuropsychologia ; 202: 108956, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-39002772

RESUMO

The neural underpinning of cooperative and competitive constructive activity has been investigated using mass-univariate approaches. In this study, we sought to compare the results of these approaches with the results of multivariate pattern analysis (MVPA). In particular, we wanted to test whether MVPA supports the claim made in previous studies that cooperation is associated with the activity of reward-related brain circuits. Participants were required to construct a pattern on the screen either individually or in cooperation or competition with another person during an fMRI scan. Both the MVPA classification methods and the representational similarity analysis indicated the involvement of orbitofrontal and ventromedial prefrontal areas in processes that distinguish between cooperation and competition, and activation analysis showed that these areas are more active during cooperation than during competition. However, a single trial analysis showed that the effect was reversed when only winning trials were considered. In these trials, activation of reward-related areas was higher during competition than during cooperation. Moreover, the contrast between won and lost trials in terms of reward circuits involvement was sharper under competition than under cooperation. Thus, although cooperation can be generally more rewarding than competition, it is associated with smaller difference between trials lost and trials won in terms of reward circuits activation. One may speculate that in cooperation, victory and defeat are shared with the partner and, contrary to competition, are not experienced as personal achievement or failure.

7.
Sci Justice ; 64(4): 408-420, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39025566

RESUMO

Classifying bloodstains is an essential part of Bloodstain Pattern Analysis. Various experts have developed methods. Each method considers the same basic bloodstain pattern types. These use either terminology based on the observable characteristics or the mechanistic cause of the bloodstain patterns as part of the classification process. This review paper considers ten classification methods from fourteen sources, which are used to classify bloodstain patterns. There are fundamental differences in how the patterns are classified, how differentiated the classification is, and whether the classification process uses clear, unambiguous criteria, and is susceptible to contextual bias. Experts have also reported issues with classifying bloodstains that have indistinguishable features. These differences expose key limitations with current classification methods: mechanistic terminology is too heavily relied on, and the classification process is susceptible to contextual bias. The development of an unambiguous classification method, based on directly observable characteristics within bloodstain patterns is recommended for future work.


Assuntos
Manchas de Sangue , Humanos , Terminologia como Assunto
8.
Parasitol Res ; 123(7): 262, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38970660

RESUMO

Malaria poses a significant threat to global health, with particular severity in Nigeria. Understanding key factors influencing health outcomes is crucial for addressing health disparities. Disease mapping plays a vital role in assessing the geographical distribution of diseases and has been instrumental in epidemiological research. By delving into the spatiotemporal dynamics of malaria trends, valuable insights can be gained into population dynamics, leading to more informed spatial management decisions. This study focused on examining the evolution of malaria in Nigeria over twenty years (2000-2020) and exploring the impact of environmental factors on this variation. A 5-year-period raster map was developed using malaria indicator survey data for Nigeria's six geopolitical zones. Various spatial analysis techniques, such as point density, spatial autocorrelation, and hotspot analysis, were employed to analyze spatial patterns. Additionally, statistical methods, including Principal Component Analysis, Spearman correlation, and Ordinary Least Squares (OLS) regression, were used to investigate relationships between indicators and develop a predictive model. The study revealed regional variations in malaria prevalence over time, with the highest number of cases concentrated in northern Nigeria. The raster map illustrated a shift in the distribution of malaria cases over the five years. Environmental factors such as the Enhanced Vegetation Index, annual land surface temperature, and precipitation exhibited a strong positive association with malaria cases in the OLS model. Conversely, insecticide-treated bed net coverage and mean temperature negatively correlated with malaria cases in the same model. The findings from this research provide valuable insights into the spatiotemporal patterns of malaria in Nigeria and highlight the significant role of environmental drivers in influencing disease transmission. This scientific knowledge can inform policymakers and aid in developing targeted interventions to combat malaria effectively.


Assuntos
Sistemas de Informação Geográfica , Malária , Análise Espaço-Temporal , Nigéria/epidemiologia , Malária/epidemiologia , Malária/transmissão , Humanos , Prevalência
9.
Lang Cogn Neurosci ; 39(5): 632-656, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39040138

RESUMO

The sentences "More than half of the students passed the exam" and "Fewer than half of the students failed the exam" describe the same set of situations, and yet the former results in shorter reaction times in verification tasks. The two-step model explains this result by postulating that negative quantifiers contain hidden negation, which involves an extra processing stage. To test this theory, we applied a novel EEG analysis technique focused on detecting cognitive stages (HsMM-MVPA) to data from a picture-sentence verification task. We estimated the number of processing stages during reading and verification of quantified sentences (e.g. "Fewer than half of the dots are blue") that followed the presentation of pictures containing coloured geometric shapes. We did not find evidence for an extra step during the verification of sentences with fewer than half. We provide an alternative interpretation of our results in line with an expectation-based pragmatic account.

10.
Forensic Sci Int ; 361: 112140, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39024802

RESUMO

Bloodstain pattern analysis plays a crucial role in forensic investigations. Projected patterns can offer valuable insights into the dynamics of crime scenes. In this paper, we propose and validate a novel approach that extends existing software, HemoVision, to analyze impact patterns that are distributed across multiple arbitrarily oriented surfaces. The proposed method integrates HemoVision's marker-based system with structure from motion (SfM) techniques to reconstruct the three-dimensional geometry of impact patterns using only two-dimensional photographs. Controlled experiments were used to validate the proposed approach, demonstrating robustness in reconstruction accuracy with median translation errors below 3 mm and median angular errors below 0.2°, irrespective of imaging device or image resolution. Comparing the estimated areas origin to their known ground truth, the proposed method achieved an average total error of 8.12 cm, with the primary source of error being the vertical dimension. Despite this, the overall error remains well within the ranges of error reported in prior work. This study demonstrates that HemoVision can be used to analyze complex impact patterns using only two-dimensional photographs, providing forensic experts with an efficient and accessible tool for investigating intricate crime scenes involving multi-surface impact patterns.

11.
Neuroimage ; 297: 120760, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39069225

RESUMO

Identifying and segmenting objects in an image is generally achieved effortlessly and is facilitated by the presence of symmetry: a principle of perceptual organisation used to interpret sensory inputs from the retina into meaningful representations. However, while imaging studies show evidence of symmetry selective responses across extrastriate visual areas in the human brain, whether symmetry is processed automatically is still under debate. We used functional Magnetic Resonance Imaging (fMRI) to study the response to and representation of two types of symmetry: reflection and rotation. Dot pattern stimuli were presented to 15 human participants (10 female) under stimulus-relevant (symmetry) and stimulus-irrelevant (luminance) task conditions. Our results show that symmetry-selective responses emerge from area V3 and extend throughout extrastriate visual areas. This response is largely maintained when participants engage in the stimulus irrelevant task, suggesting an automaticity to processing visual symmetry. Our multi-voxel pattern analysis (MVPA) results extend these findings by suggesting that not only spatial organisation of responses to symmetrical patterns can be distinguished from that of non-symmetrical (random) patterns, but also that representation of reflection and rotation symmetry can be differentiated in extrastriate and object-selective visual areas. Moreover, task demands did not affect the neural representation of the symmetry information. Intriguingly, our MVPA results show an interesting dissociation: representation of luminance (stimulus irrelevant feature) is maintained in visual cortex only when task relevant, while information of the spatial configuration of the stimuli is available across task conditions. This speaks in favour of the automaticity for processing perceptual organisation: extrastriate visual areas compute and represent global, spatial properties irrespective of the task at hand.

12.
Neuroimage Clin ; 43: 103640, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39033631

RESUMO

BACKGROUND: Widespread functional alterations have been implicated in patients with generalized anxiety disorder (GAD). However, most studies have primarily focused on static brain network features in patients with GAD. The current research focused on exploring the dynamics within functional brain networks among individuals diagnosed with GAD. METHODS: Seventy-five participants were divided into patients with GAD and healthy controls (HCs), and resting-state functional magnetic resonance imaging data were collected. The severity of symptoms was measured using the Hamilton Anxiety Scale and the Patient Health Questionnaire. Co-activation pattern (CAP) analysis, centered on the bed nucleus of the stria terminalis, was applied to explore network dynamics. The capability of these dynamic characteristics to distinguish between patients with GAD and HCs was evaluated using a support vector machine. RESULTS: Patients with GAD exhibited disruptions in the limbic-prefrontal and limbic-default-mode network circuits. Particularly noteworthy was the marked reduction in dynamic indicators such as occurrence, EntriesFromBaseline, ExitsToBaseline, in-degree, out-degree, and resilience. Moreover, these decreased dynamic features effectively distinguished the GAD group from the HC in this study. CONCLUSIONS: The current findings revealed the underlying brain networks associated with compromised emotion regulation in individuals with GAD. The dynamic reduction in connectivity between the limbic-default mode network and limbic-prefrontal networks could potentially act as a biomarker and therapeutic target for GAD in the future.

13.
Sci Rep ; 14(1): 15846, 2024 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982142

RESUMO

Recognition memory research has identified several electrophysiological indicators of successful memory retrieval, known as old-new effects. These effects have been observed in different sensory domains using various stimulus types, but little attention has been given to their similarity or distinctiveness and the underlying processes they may share. Here, a data-driven approach was taken to investigate the temporal evolution of shared information content between different memory conditions using openly available EEG data from healthy human participants of both sexes, taken from six experiments. A test dataset involving personally highly familiar and unfamiliar faces was used. The results show that neural signals of recognition memory for face stimuli were highly generalized starting from around 200 ms following stimulus onset. When training was performed on non-face datasets, an early (around 200-300 ms) to late (post-400 ms) differentiation was observed over most regions of interest. Successful cross-classification for non-face stimuli (music and object/scene associations) was most pronounced in late period. Additionally, a striking dissociation was observed between familiar and remembered objects, with shared signals present only in the late window for correctly remembered objects, while cross-classification for familiar objects was successful in the early period as well. These findings suggest that late neural signals of memory retrieval generalize across sensory modalities and stimulus types, and the dissociation between familiar and remembered objects may provide insight into the underlying processes.


Assuntos
Eletroencefalografia , Reconhecimento Psicológico , Humanos , Masculino , Feminino , Reconhecimento Psicológico/fisiologia , Adulto , Adulto Jovem , Rememoração Mental/fisiologia , Encéfalo/fisiologia , Estimulação Luminosa
14.
Front Psychiatry ; 15: 1354762, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38895036

RESUMO

Borderline Personality Disorder (BPD) symptoms include inappropriate control of anger and severe emotional dysregulation after rejection in daily life. Nevertheless, when using the Cyberball paradigm, a tossing game to simulate social exclusion, the seven basic emotions (happiness, sadness, anger, surprise, fear, disgust, and contempt) have not been exhaustively tracked out. It was hypothesized that these patients would show anger, contempt, and disgust during the condition of exclusion versus the condition of inclusion. When facial emotions are automatically detected by Artificial Intelligence, "blending", -or a mixture of at least two emotions- and "masking", -or showing happiness while expressing negative emotions- may be most easily traced expecting higher percentages during exclusion rather than inclusion. Therefore, face videos of fourteen patients diagnosed with BPD (26 ± 6 years old), recorded while playing the tossing game, were analyzed by the FaceReader software. The comparison of conditions highlighted an interaction for anger: it increased during inclusion and decreased during exclusion. During exclusion, the masking of surprise; i.e., displaying happiness while feeling surprised, was significantly more expressed. Furthermore, disgust and contempt were inversely correlated with greater difficulties in emotion regulation and symptomatology, respectively. Therefore, the automatic detection of emotional expressions during both conditions could be useful in rendering diagnostic guidelines in clinical scenarios.

15.
Neurosci Bull ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38900383

RESUMO

Fairness is a fundamental value in human societies, with individuals concerned about unfairness both to themselves and to others. Nevertheless, an enduring debate focuses on whether self-unfairness and other-unfairness elicit shared or distinct neuropsychological processes. To address this, we combined a three-person ultimatum game with computational modeling and advanced neuroimaging analysis techniques to unravel the behavioral, cognitive, and neural patterns underlying unfairness to self and others. Our behavioral and computational results reveal a heightened concern among participants for self-unfairness over other-unfairness. Moreover, self-unfairness consistently activates brain regions such as the anterior insula, dorsal anterior cingulate cortex, and dorsolateral prefrontal cortex, spanning various spatial scales that encompass univariate activation, local multivariate patterns, and whole-brain multivariate patterns. These regions are well-established in their association with emotional and cognitive processes relevant to fairness-based decision-making. Conversely, other-unfairness primarily engages the middle occipital gyrus. Collectively, our findings robustly support distinct neurocomputational signatures between self-unfairness and other-unfairness.

16.
Neuroimage ; 297: 120692, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38897398

RESUMO

Errors typically trigger post-error adjustments aimed at improving subsequent reactions within a single task, but little work has focused on whether these adjustments are task-general or task-specific across different tasks. We collected behavioral and electrophysiological (EEG) data when participants performed a psychological refractory period paradigm. This paradigm required them to complete Task 1 and Task 2 separated by a variable stimulus onset asynchrony (SOA). Behaviorally, post-error slowing and post-error accuracy exhibited task-general features at short SOAs but some task-specific features at long SOAs. EEG results manifest that task-general adjustments had a short-lived effect, whereas task-specific adjustments were long-lasting. Moreover, error awareness specifically conduced to the improvement of subsequent sensory processing and behavior performance in Task 1 (the task where errors occurred). These findings demonstrate that post-error adjustments rely on both transient, task-general interference and longer-lasting, task-specific control mechanisms simultaneously, with error awareness playing a crucial role in determining these mechanisms. We further discuss the contribution of central resources to the task specificity of post-error adjustments.

17.
Neuroimage ; 296: 120668, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38848982

RESUMO

Our brain excels at recognizing objects, even when they flash by in a rapid sequence. However, the neural processes determining whether a target image in a rapid sequence can be recognized or not remains elusive. We used electroencephalography (EEG) to investigate the temporal dynamics of brain processes that shape perceptual outcomes in these challenging viewing conditions. Using naturalistic images and advanced multivariate pattern analysis (MVPA) techniques, we probed the brain dynamics governing conscious object recognition. Our results show that although initially similar, the processes for when an object can or cannot be recognized diverge around 180 ms post-appearance, coinciding with feedback neural processes. Decoding analyses indicate that gist perception (partial conscious perception) can occur at ∼120 ms through feedforward mechanisms. In contrast, object identification (full conscious perception of the image) is resolved at ∼190 ms after target onset, suggesting involvement of recurrent processing. These findings underscore the importance of recurrent neural connections in object recognition and awareness in rapid visual presentations.


Assuntos
Estado de Consciência , Eletroencefalografia , Reconhecimento Visual de Modelos , Humanos , Feminino , Masculino , Eletroencefalografia/métodos , Adulto , Estado de Consciência/fisiologia , Adulto Jovem , Reconhecimento Visual de Modelos/fisiologia , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Reconhecimento Psicológico/fisiologia , Estimulação Luminosa/métodos
18.
Artigo em Inglês | MEDLINE | ID: mdl-38852918

RESUMO

BACKGROUND: The sex differences were co-shaped by innate biological differences and social environment, and were frequently observed in human emotional neural responses. Oral administration of oxytocin, as an alternative and noninvasive intake method, has been demonstrated to produce sex-dependent effects on emotional face processing. However, it is unclear whether oral oxytocin produces similar sex-dependent effects on processing continuous emotional scenes. METHODS: Current randomized, double-blind, placebo-controlled neuro-psychopharmacological fMRI experiment was conducted in 147 healthy participants (oxytocin=74, male/female=37/37; placebo=73, male/female=36/37) to examine the oral oxytocin effect on plasma oxytocin concentrations and neural response to emotional scenes in both sexes. RESULTS: At the neuroendocrine level, females showed lower endogenous oxytocin concentrations than males, but oral oxytocin equally increased the oxytocin concentrations in both sexes. Regarding neural activity, emotional scenes evoked opposite valence-independent effects on right amygdala activation (females>males) and its functional connectivity with the insula (males>females) in two sexes in the placebo group. This sex difference were either attenuated (amygdala response) or even completely eliminated (amygdala-insula functional connectivity) in the oxytocin group. The multivariate pattern analysis confirmed these findings by developing an accurate sex-predictive neural pattern that including the amygdala and the insula under the placebo but not oxytocin condition. CONCLUSION: Present study suggests a pronounced sex-difference in neural responses to emotional scenes which is abolished by oral oxytocin, with it having opposite modulatory effects in two sexes. Possibly this may reflect oral OXT enhancing emotional regulation to continuous emotional stimuli in both sexes by facilitating appropriate changes in sex-specific amygdala-insula circuitry.

19.
Hum Brain Mapp ; 45(8): e26719, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38826009

RESUMO

Gilles de la Tourette syndrome (GTS) is a disorder characterised by motor and vocal tics, which may represent habitual actions as a result of enhanced learning of associations between stimuli and responses (S-R). In this study, we investigated how adults with GTS and healthy controls (HC) learn two types of regularities in a sequence: statistics (non-adjacent probabilities) and rules (predefined order). Participants completed a visuomotor sequence learning task while EEG was recorded. To understand the neurophysiological underpinnings of these regularities in GTS, multivariate pattern analyses on the temporally decomposed EEG signal as well as sLORETA source localisation method were conducted. We found that people with GTS showed superior statistical learning but comparable rule-based learning compared to HC participants. Adults with GTS had different neural representations for both statistics and rules than HC adults; specifically, adults with GTS maintained the regularity representations longer and had more overlap between them than HCs. Moreover, over different time scales, distinct fronto-parietal structures contribute to statistical learning in the GTS and HC groups. We propose that hyper-learning in GTS is a consequence of the altered sensitivity to encode complex statistics, which might lead to habitual actions.


Assuntos
Eletroencefalografia , Síndrome de Tourette , Humanos , Síndrome de Tourette/fisiopatologia , Masculino , Adulto , Feminino , Adulto Jovem , Aprendizagem/fisiologia , Desempenho Psicomotor/fisiologia , Pessoa de Meia-Idade , Aprendizagem por Probabilidade
20.
Cereb Cortex ; 34(6)2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38863114

RESUMO

When reminded of an unpleasant experience, people often try to exclude the unwanted memory from awareness, a process known as retrieval suppression. Here we used multivariate decoding (MVPA) and representational similarity analyses on EEG data to track how suppression unfolds in time and to reveal its impact on item-specific cortical patterns. We presented reminders to aversive scenes and asked people to either suppress or to retrieve the scene. During suppression, mid-frontal theta power within the first 500 ms distinguished suppression from passive viewing of the reminder, indicating that suppression rapidly recruited control. During retrieval, we could discern EEG cortical patterns relating to individual memories-initially, based on theta-driven visual perception of the reminders (0 to 500 ms) and later, based on alpha-driven reinstatement of the aversive scene (500 to 3000 ms). Critically, suppressing retrieval weakened (during 360 to 600 ms) and eventually abolished item-specific cortical patterns, a robust effect that persisted until the reminder disappeared (780 to 3000 ms). Representational similarity analyses provided converging evidence that retrieval suppression weakened the representation of target scenes during the 500 to 3000 ms reinstatement window. Together, rapid top-down control during retrieval suppression abolished cortical patterns of individual memories, and precipitated later forgetting. These findings reveal a precise chronometry on the voluntary suppression of individual memories.


Assuntos
Conscientização , Eletroencefalografia , Rememoração Mental , Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Conscientização/fisiologia , Rememoração Mental/fisiologia , Estado de Consciência/fisiologia , Memória/fisiologia , Percepção Visual/fisiologia , Encéfalo/fisiologia
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