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1.
Prog Brain Res ; 283: 305-325, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38538192

RESUMO

An increasing number of studies have linked engagement in sport or increased physical fitness with improved cognitive performance. Additionally, studies have employed physical activity as an intervention to help with cognition in aging individuals. Despite this, the underlying mechanism (or mechanisms) by which benefits occur remain unclear. We investigated whether improved trainability for individuals engaged in sport or fitness training might underlie such benefits. Specifically, we assessed motor skill performance and learning rates in young adult runners, baseball players, and "control" individuals who did not regularly engage in sport or exercise using an implicit motor sequence learning task. Better initial performance on the task was seen for both the runner group and the baseball group but no benefits were seen for the baseball/runner groups for rates of improvement on the task. This was the case for both non-specific learning (or general motor skill learning-learning not associated with specific sequences of responses) and for sequence-specific learning (or improvement on repeated sequences of responses that participants were not aware of). This pattern may mean that either engagement in sport/physical activity results in improvements that are transferable beyond the context of the sport/training activity or that engagement in sport/exercise may relate to initial differences in the motor competence of an individual. Further work could beneficially investigate learning in more directly cognitive-related tasks and consolidation/improvement of performance over more prolonged time periods. Importantly, assessment of a fitness/sport intervention on performance and learning rates may provide a better context for some of the benefits reported in cross-sectional investigations of the effects of sport/fitness on cognition and aid in determining which differences are due to engaging in exercise and which differences affect the tendency for such engagement.


Assuntos
Esportes , Adulto Jovem , Humanos , Estudos Transversais , Cognição/fisiologia , Aprendizagem , Exercício Físico , Destreza Motora/fisiologia
2.
Psychophysiology ; 61(4): e14479, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37920144

RESUMO

The locus coeruleus-norepinephrine (LC-NE) system, which regulates arousal levels, is important for cognitive control, including emotional conflict resolution. Additionally, the LC-NE system is implicated in P300 generation. If the P300 is mediated by the LC-NE system, and considering the established correlations between LC activity and pupil dilation, P300 amplitude should correlate with task-evoked (phasic) pupil dilation on a trial-by-trial basis. However, prior studies, predominantly utilizing oddball-type paradigms, have not demonstrated correlations between concurrently recorded task-evoked pupil dilation and P300 responses. Using a recently developed emotional face-word Stroop task that links pupil dilation to the LC-NE system, here, we examined both intra- and inter-individual correlations between task-evoked pupil dilation and P300 amplitude. We found that lower accuracy, slower reaction times, and larger task-evoked pupil dilation were obtained in the incongruent compared to the congruent condition. Furthermore, we observed intra-individual correlations between task-evoked pupil dilation and P300 amplitude, with larger pupil dilation correlating with a greater P300 amplitude. In contrast, pupil dilation did not exhibit consistent correlations with N450 and N170 amplitudes. Baseline (tonic) pupil size also showed correlations with P300 and N170 amplitudes, with smaller pupil size corresponding to larger amplitude. Moreover, inter-individual differences in task-evoked pupil dilation between the congruent and incongruent conditions correlated with differences in reaction time and P300 amplitude, though these effects only approached significance. To summarize, our study provides evidence for a connection between task-evoked pupil dilation and P300 amplitude at the single-trial level, suggesting the involvement of the LC-NE system in P300 generation.


Assuntos
Nível de Alerta , Pupila , Humanos , Teste de Stroop , Pupila/fisiologia , Tempo de Reação/fisiologia , Nível de Alerta/fisiologia , Locus Cerúleo/fisiologia , Norepinefrina/fisiologia
3.
IBRO Neurosci Rep ; 15: 364-375, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38046886

RESUMO

Pupil size undergoes constant changes primarily influenced by ambient luminance. These changes are referred to as the pupillary light reflex (PLR), where the pupil transiently constricts in response to light. PLR kinematics provides valuable insights into autonomic nervous system function and have significant clinical applications. Recent research indicates that attention plays a role in modulating the PLR, and the circuit involving the frontal eye field (FEF) and superior colliculus is causally involved in controlling this pupillary modulation. However, there is limited research exploring the role of the human FEF in these pupillary responses, and its impact on PLR metrics remains unexplored. Additionally, although the protocol of continuous theta-burst stimulation (cTBS) is well-established, the period of disruption after cTBS is yet to be examined in pupillary responses. Our study aimed to investigate the effects of FEF cTBS on pupillary and saccadic metrics in relation to time spent performing a task (referred to as time-on-task). We presented a bright stimulus to induce the PLR in visual- and memory-delay saccade tasks following cTBS over the right FEF or vertex. FEF cTBS, compared to vertex cTBS, resulted in decreased baseline pupil size, peak constriction velocities, and amplitude. Furthermore, the time-on-task effects on baseline pupil size, peak amplitude, and peak time differed between the two stimulation conditions. In contrast, the time-on-task effects on saccadic metrics were less pronounced between the two conditions. In summary, our study provides the first evidence that FEF cTBS affects human PLR metrics and that these effects are modulated by time-on-task.

4.
Sci Rep ; 13(1): 14252, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37653059

RESUMO

Electrophysiological working memory (WM) research shows brain areas communicate via macroscopic oscillations across frequency bands, generating nonlinear amplitude modulation (AM) in the signal. Traditionally, AM is expressed as the coupling strength between the signal and a prespecified modulator at a lower frequency. Therefore, the idea of AM and coupling cannot be studied separately. In this study, 33 participants completed a color recall task while their brain activity was recorded through EEG. The AM of the EEG data was extracted using the Holo-Hilbert spectral analysis (HHSA), an adaptive method based on the Hilbert-Huang transforms. The results showed that WM load modulated parieto-occipital alpha/beta power suppression. Furthermore, individuals with higher frontal theta power and lower parieto-occipital alpha/beta power exhibited superior WM precision. In addition, the AM of parieto-occipital alpha/beta power predicted WM precision after presenting a target-defining probe array. The phase-amplitude coupling (PAC) between the frontal theta phase and parieto-occipital alpha/beta AM increased with WM load while processing incoming stimuli, but the PAC itself did not predict the subsequent recall performance. These results suggest frontal and parieto-occipital regions communicate through theta-alpha/beta PAC. However, the overall recall precision depends on the alpha/beta AM following the onset of the retro cue.


Assuntos
Gastrópodes , Memória de Curto Prazo , Humanos , Animais , Dinâmica não Linear , Encéfalo , Eletrofisiologia Cardíaca , Eletroencefalografia
5.
IBRO Neurosci Rep ; 14: 122-128, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36718196

RESUMO

Drug use causes significant social and financial problems and these are exacerbated by difficulties in stopping use and subsequent maintenance of abstinence. There is also difficulty in identifying the beneficial treatment for an individual, made more problematic given the high drop-out rates in treatment programs. Here, the effects of transcranial direct current stimulation (tDCS) on the amplitude of the P300 event-related potential component, previously suggested to be indicative of successful remission, was measured in recently abstinent amphetamine users. This component was collected during a Posner cuing task which was presented to this group and to control (non-user) participants, using task cues of neutral and drug-related images. The abstinent drug users were divided into two groups, one of which received tDCS daily for five days, with the cathode over the left dorsolateral prefrontal cortex (DLPFC) and the anode over the right DLPFC, and one receiving sham stimulation over the same time period. Behavioral performance and P300 amplitudes were measured before and after the period of tDCS delivery. Control participants were tested with the same time-schedule of task presentation but without administration of tDCS. Drug users initially showed a larger cost of invalid cues on task performance compared to control (non-drug user) participants and this was reduced following delivery of tDCS. Additionally, tDCS resulted in increased amplitude of the P300 component, significantly so for neutral cues, with the resulting pattern being more similar to that of the non-users. This provides a good basis for further investigation of both the utility of tDCS in modulation of cognition in addict groups, and to investigate the effects of modulating the P300 component on remission rates, a relationship that seems to be the case for this measure without use of tDCS modulation. Importantly, this study also provides a further addiction group showing P300 amplitude modulation as a result of tDCS administration.

6.
Front Hum Neurosci ; 16: 796180, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35496071

RESUMO

Violence has been linked to the co-occurrence of cognitive dysfunction and altered activations in several brain regions. Empirical evidence demonstrated the benefits of acute exercise on motor inhibition and error detection and their neuronal processing. However, whether such effects also hold for the population with violent behaviors remains unknown. This study examined the effects of acute aerobic exercise on inhibitory control and error monitoring among violent offenders. Fifteen male violent offenders were counterbalanced into experimental protocols, which comprised a 30-min moderately aerobic exercise [60% heart rate (HR) reserve] and a 30-min reading control session. After each session, participants performed an emotional stop signal task while event-related potentials (ERPs) were recorded simultaneously. Results showed insignificant changes in ERPs components [i.e., N2, P3, error-related negativity (ERN), and error-positivity (Pe) amplitudes] and the behavioral performance in go condition, stop accuracy, and post-error adjustments by exercise. However, the current study demonstrated that the acute exercise facilitated stop signal reaction time (SSRT) when compared to the control session regardless of emotional conditions. This is the first research to exhibit the improvements in inhibitory performance by acute exercise for violent offenders. Most importantly, this effect was independent of affective settings, expanding the existing knowledge of the influences of acute exercise on cognition. Our findings implicate the perspective of acute exercise for clinical and correctional practices.

7.
Hum Brain Mapp ; 43(5): 1535-1547, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34873781

RESUMO

Repetitive transcranial magnetic stimulation (rTMS) is an alternative treatment for depression, but the neural correlates of the treatment are currently inconclusive, which might be a limit of conventional analytical methods. The present study aimed to investigate the neurophysiological evidence and potential biomarkers for rTMS and intermittent theta burst stimulation (iTBS) treatment. A total of 61 treatment-resistant depression patients were randomly assigned to receive prolonged iTBS (piTBS; N = 19), 10 Hz rTMS (N = 20), or sham stimulation (N = 22). Each participant went through a treatment phase with resting state electroencephalography (EEG) recordings before and after the treatment phase. The aftereffects of stimulation showed that theta-alpha amplitude modulation frequency (fam ) was associated with piTBS_Responder, which involves repetitive bursts delivered in the theta frequency range, whereas alpha carrier frequency (fc ) was related to 10 Hz rTMS, which uses alpha rhythmic stimulation. In addition, theta-alpha amplitude modulation frequency was positively correlated with piTBS antidepressant efficacy, whereas the alpha frequency was not associated with the 10 Hz rTMS clinical outcome. The present study showed that TMS stimulation effects might be lasting, with changes of brain oscillations associated with the delivered frequency. Additionally, theta-alpha amplitude modulation frequency may be as a function of the degree of recovery in TRD with piTBS treatment and also a potential EEG-based predictor of antidepressant efficacy of piTBS in the early treatment stage, that is, first 2 weeks.


Assuntos
Transtorno Depressivo Resistente a Tratamento , Estimulação Magnética Transcraniana , Antidepressivos/uso terapêutico , Depressão , Transtorno Depressivo Resistente a Tratamento/terapia , Humanos , Córtex Pré-Frontal/fisiologia , Estimulação Magnética Transcraniana/métodos
8.
Front Neurosci ; 15: 673369, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34421511

RESUMO

Patterns in external sensory stimuli can rapidly entrain neuronally generated oscillations observed in electrophysiological data. Here, we manipulated the temporal dynamics of visual stimuli with cross-frequency coupling (CFC) characteristics to generate steady-state visual evoked potentials (SSVEPs). Although CFC plays a pivotal role in neural communication, some cases reporting CFC may be false positives due to non-sinusoidal oscillations that can generate artificially inflated coupling values. Additionally, temporal characteristics of dynamic and non-linear neural oscillations cannot be fully derived with conventional Fourier-based analyses mainly due to trade off of temporal resolution for frequency precision. In an attempt to resolve these limitations of linear analytical methods, Holo-Hilbert Spectral Analysis (HHSA) was investigated as a potential approach for examination of non-linear and non-stationary CFC dynamics in this study. Results from both simulation and SSVEPs demonstrated that temporal dynamic and non-linear CFC features can be revealed with HHSA. Specifically, the results of simulation showed that the HHSA is less affected by the non-sinusoidal oscillation and showed possible cross frequency interactions embedded in the simulation without any a priori assumptions. In the SSVEPs, we found that the time-varying cross-frequency interaction and the bidirectional coupling between delta and alpha/beta bands can be observed using HHSA, confirming dynamic physiological signatures of neural entrainment related to cross-frequency coupling. These findings not only validate the efficacy of the HHSA in revealing the natural characteristics of signals, but also shed new light on further applications in analysis of brain electrophysiological data with the aim of understanding the functional roles of neuronal oscillation in various cognitive functions.

9.
PLoS One ; 16(8): e0256272, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34398917

RESUMO

To properly behave and correct mistakes, individuals must inhibit inappropriate actions and detect errors for future behavioral adjustment. Increasing evidence has demonstrated that athletes are superior in cognitive functions and this benefit varied dependent on the types of sport that individuals involved in, but less is known on whether athletes have a different error-related behavioral pattern. The purpose of this study was to compare the behavioral performance of inhibition and error monitoring between individuals who participated in an open-skill sport (n = 12), a closed-skill sport (n = 12), and a sedentary lifestyle (n = 16). A combined flanker/stop signal task was presented and the derived stop signal reaction time (SSRT), post-correct accuracy and reaction time (RT), as well as post-error accuracy and RT were compared across groups. Our findings indicated there was no difference in SSRT between groups. Surprisingly, significant post-error slowing (PES) was observed only in controls but not in sport groups, the controls also exhibited significantly longer post-error RT compared with the open-skill group. However, there was no difference in the post-error accuracy between groups, indicating a higher efficiency in the post-error processing among open- and closed-skill groups by requiring comparatively less time for behavioral adjustments. The present study is the first to disclose the discrepancies in PES between different types of athletes and controls. The findings suggest that sport training along with higher amounts of physical activity is associated with a more efficient behavioral pattern for error processing especially when the sport requires open skills in nature.


Assuntos
Atletas/psicologia , Cognição/fisiologia , Função Executiva/fisiologia , Inibição Psicológica , Desempenho Psicomotor/fisiologia , Feminino , Humanos , Masculino , Tempo de Reação/fisiologia , Comportamento Sedentário , Natação/fisiologia , Luta Romana/fisiologia , Adulto Jovem
10.
Brain Sci ; 11(4)2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33918711

RESUMO

Response inhibition has been widely explored using the stop signal paradigm in the laboratory setting. However, the mechanism that demarcates attentional capture from the motor inhibition process is still unclear. Error monitoring is also involved in the stop signal task. Error responses that do not complete, i.e., partial errors, may require different error monitoring mechanisms relative to an overt error. Thus, in this study, we included a "continue go" (Cont_Go) condition to the stop signal task to investigate the inhibitory control process. To establish the finer difference in error processing (partial vs. full unsuccessful stop (USST)), a grip-force device was used in tandem with electroencephalographic (EEG), and the time-frequency characteristics were computed with Hilbert-Huang transform (HHT). Relative to Cont_Go, HHT results reveal (1) an increased beta and low gamma power for successful stop trials, indicating an electrophysiological index of inhibitory control, (2) an enhanced theta and alpha power for full USST trials that may mirror error processing. Additionally, the higher theta and alpha power observed in partial over full USST trials around 100 ms before the response onset, indicating the early detection of error and the corresponding correction process. Together, this study extends our understanding of the finer motor inhibition control and its dynamic electrophysiological mechanisms.

11.
Front Hum Neurosci ; 15: 614978, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33584231

RESUMO

A critical issue in executive control is how the nervous system exerts flexibility to inhibit a prepotent response and adapt to sudden changes in the environment. In this study, force measurement was used to capture "partial" unsuccessful trials that are highly relevant in extending the current understanding of motor inhibition processing. Moreover, a modified version of the stop-signal task was used to control and eliminate potential attentional capture effects from the motor inhibition index. The results illustrate that the non-canceled force and force rate increased as a function of stop-signal delay (SSD), offering new objective indices for gauging the dynamic inhibitory process. Motor response (time and force) was a function of delay in the presentation of novel/infrequent stimuli. A larger lateralized readiness potential (LRP) amplitude in go and novel stimuli indicated an influence of the novel stimuli on central motor processing. Moreover, an early N1 component reflects an index of motor inhibition in addition to the N2 component reported in previous studies. Source analysis revealed that the activation of N2 originated from inhibitory control associated areas: the right inferior frontal gyrus (rIFG), pre-motor cortex, and primary motor cortex. Regarding partial responses, LRP and error-related negativity (ERNs) were associated with error correction processes, whereas the N2 component may indicate the functional overlap between inhibition and error correction. In sum, the present study has developed reliable and objective indices of motor inhibition by introducing force, force-rate and electrophysiological measures, further elucidating our understandings of dynamic motor inhibition and error correction.

12.
Cortex ; 132: 79-91, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32956909

RESUMO

Soccer is the only major sport with voluntary unprotected head-to-ball contact. It is crucial to determine if head impact through long-term soccer training is manifested in brain structure and connectivity, and whether such alterations are due to sustained training per se. Using diffusion tensor imaging, we documented a comprehensive view of soccer players' brains in a sample of twenty-five right-handed male elite soccer players aged from 18 to 22 years and twenty-five non-athletic controls aged 19-24 years. Importantly, none had recalled a history of concussion. We performed a whole-brain tract-based spatial statistical analysis, and a tract-specific probabilistic tractography method to measure the differences of white matter properties between groups. Whole-brain integrity analysis showed stronger microstructural integrity within the corpus callosum tract in soccer players compared to controls. Further, tract-specific probabilistic tractography revealed that the anterior part of corpus callosum may be the brain structure most relevant to training experience, which may put into perspective prior evidence showing corpus callosum alteration in retired or concussed athletes practicing contact sports. Intriguingly, experience-related alterations showed left hemispheric lateralization of potential early signs of concussion-like effects. In sum, we concluded that the observed gains and losses may be due to a consequence of engagement in protracted soccer training that incurs prognostic hallmarks associated with minor injury-induced neural inflammation.


Assuntos
Traumatismos em Atletas , Futebol , Substância Branca , Encéfalo/diagnóstico por imagem , Imagem de Tensor de Difusão , Humanos , Masculino , Substância Branca/diagnóstico por imagem
13.
Prog Brain Res ; 253: 201-227, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32771124

RESUMO

While there has been a marked increase in investigation of benefits of sporting engagement and fitness beyond typical health benefits, particularly looking at beneficial effects on cognitive ability, there has been less investigation of whether cognitive training can benefit sporting-specific skills. Here, the effects of simple cognitive training on a sport-related skill were assessed, with the specific hypothesis that training on a visual tracking task would improve the ability of volleyball players to spike the ball on a volleyball court (the volleyball equivalent of a tennis smash). Following training with such a task, improvement in spiking performance was seen when the target was indicated before spike execution but not when it was indicated during execution. There was some retention of the spiking improvements 1 month after visual task training. No improvements were seen when a cognitive task with no motion was used for training such that the results suggest benefits of appropriate cognitive training on aspects of sporting skills. Future work could beneficially assess application to a more sporting environment, evaluate the suitability of different cognitive training, and see if effects are seen in individuals with higher sporting skill.


Assuntos
Desempenho Atlético/fisiologia , Prática Psicológica , Desempenho Psicomotor/fisiologia , Percepção Espacial/fisiologia , Percepção Visual/fisiologia , Voleibol/fisiologia , Adulto , Feminino , Humanos , Masculino , Percepção de Movimento/fisiologia , Adulto Jovem
14.
Prog Brain Res ; 253: 229-242, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32771125

RESUMO

The possibility that improved inhibitory control in older adults is associated with engagement in non-contact sporting activity, Tai Chi, was investigated. Three groups of participants were compared; a group who regularly took part in Tai Chi (TC), a regularly exercising (RE) group, and a sedentary group (SG). Concurrent electroencephalographic recordings were obtained while a stop-signal inhibitory control task, where speeded responses are needed for most trials, but these must occasionally be withheld when a 'stop signal' is displayed, was performed. The electrophysiological components P3, broadly related to decision making, and Pe, related to error monitoring, were analyzed. Both exercise groups performed better on the stop-signal task for the measure indicative of inhibitory control, as well as being generally better for other indices of performance. No significant effects were seen for post-error slowing. Electrophysiological differences were seen for the TC group, with a significantly larger P3 component related to the stop-signal and a larger Pe component when errors were made. This indicated that the TC group seemed to show better decision making and have better awareness of errors. Future work should investigate whether such effects are seen when this type of exercise is applied as an 'intervention' in non-exercising individuals.


Assuntos
Envelhecimento/fisiologia , Potenciais Evocados/fisiologia , Função Executiva/fisiologia , Exercício Físico/fisiologia , Inibição Psicológica , Desempenho Psicomotor/fisiologia , Tai Chi Chuan , Eletroencefalografia , Potenciais Evocados P300/fisiologia , Humanos , Pessoa de Meia-Idade
15.
J Vis ; 19(14): 14, 2019 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-31845974

RESUMO

The response latency of steady-state visually evoked potentials (SSVEPs) is a sensitive measurement for investigating visual functioning of the human brain, specifically in visual development and for clinical evaluation. This latency can be measured from the slope of phase versus frequency of responses by using multiple frequencies of stimuli. In an attempt to provide an alternative measurement of this latency, this study utilized an envelope response of SSVEPs elicited by amplitude-modulated visual stimulation and then compared with the envelope of the generating signal, which was recorded simultaneously with the electroencephalography recordings. The advantage of this measurement is that it successfully estimates the response latency based on the physiological envelope in the entire waveform. Results showed the response latency at the occipital lobe (Oz channel) was approximately 104.55 ms for binocular stimulation, 97.14 ms for the dominant eye, and 104.75 ms for the nondominant eye with no significant difference between these stimulations. Importantly, the response latency at frontal channels (125.84 ms) was significantly longer than that at occipital channels (104.11 ms) during binocular stimulation. Together with strong activation of the source envelope at occipital cortex, these findings support the idea of a feedforward process, with the visual stimuli propagating originally from occipital cortex to anterior cortex. In sum, these findings offer a novel method for future studies in measuring visual response latencies and also potentially shed a new light on understanding of how long collective neural activities take to travel in the human brain.


Assuntos
Encéfalo/fisiologia , Eletroencefalografia , Potenciais Evocados Visuais , Estimulação Luminosa/métodos , Tempo de Reação , Adulto , Córtex Cerebral/fisiologia , Feminino , Humanos , Masculino , Lobo Occipital/fisiologia , Processamento de Sinais Assistido por Computador , Visão Ocular , Adulto Jovem
16.
Sci Rep ; 9(1): 16919, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31729410

RESUMO

Natural sensory signals have nonlinear structures dynamically composed of the carrier frequencies and the variation of the amplitude (i.e., envelope). How the human brain processes the envelope information is still poorly understood, largely due to the conventional analysis failing to quantify it directly. Here, we used a recently developed method, Holo-Hilbert spectral analysis, and steady-state visually evoked potential collected using electroencephalography (EEG) recordings to investigate how the human visual system processes the envelope of amplitude-modulated signals, in this case with a 14 Hz carrier and a 2 Hz envelope. The EEG results demonstrated that in addition to the fundamental stimulus frequencies, 4 Hz amplitude modulation residing in 14 Hz carrier and a broad range of carrier frequencies covering from 8 to 32 Hz modulated by 2 Hz amplitude modulation are also found in the two-dimensional frequency spectrum, which have not yet been recognized before. The envelope of the stimulus is also found to dominantly modulate the response to the incoming signal. The findings thus reveal that the electrophysiological response to amplitude-modulated stimuli is more complex than could be revealed by, for example, Fourier analysis. This highlights the dynamics of neural processes in the visual system.


Assuntos
Eletroencefalografia , Fenômenos Eletrofisiológicos , Córtex Visual/fisiologia , Adulto , Análise de Dados , Potenciais Evocados Visuais , Feminino , Humanos , Masculino , Estimulação Luminosa , Vias Visuais , Adulto Jovem
17.
Soc Cogn Affect Neurosci ; 14(6): 645-655, 2019 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-31119291

RESUMO

Working memory capacity (WMC) can predict conflict control ability. Measures of both abilities are impaired by anxiety, which is often inversely linked with mindfulness. It has been shown that a combination of high mindfulness and low anxiety is associated with better conflict control and WMC. The current study explored the electrophysiology related to such behavioral differences. Two experimental groups, one with high mindfulness and low anxiety (HMLA) and one with low mindfulness and high anxiety (LMHA), performed a color Stroop task and a change detection task, both with simultaneous electroencephalogram (EEG) recording. An advanced EEG analytical approach, Hilbert-Huang transform (HHT) analysis, was employed. This is regarded as a robust method to analyze non-linear and non-stationary signals. Lower delta activity at posterior temporal and occipital regions was seen in the HMLA group for the Stroop conflict conditions and might be generally associated with higher accuracy in this group and indicative of higher attentiveness. Higher accuracy rates and WMC were seen in the HMLA group and might be specifically associated with the higher alpha activity observed in prefrontal cortex, fronto-central and centro-parietal regions in this group. Future studies should explore how mindfulness and anxiety can independently affect these cognitive functions and their associated neurophysiology.


Assuntos
Ansiedade/psicologia , Encéfalo/fisiologia , Cognição/fisiologia , Memória de Curto Prazo/fisiologia , Atenção Plena , Adolescente , Atenção/fisiologia , Mapeamento Encefálico , Eletroencefalografia , Feminino , Humanos , Masculino , Teste de Stroop , Adulto Jovem
18.
Personal Neurosci ; 2: e9, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32435744

RESUMO

Mindfulness and anxiety are often linked as inversely related traits and there have been several theoretical and mediational models proposed suggesting such a relationship between these two traits. The current review report offers an account of self-report measures, behavioral, electrophysiological, hemodynamic, and biological studies, which provide converging evidence for an inverse relationship between mindfulness and anxiety. To our knowledge, there are no comprehensive accounts of empirical evidence that investigate this relationship. After reviewing several empirical studies, we propose a schematic model, where a stressor can trigger the activation of amygdala which activates the hypothalamic-pituitary-adrenal (HPA) pathway. This hyperactive HPA axis leads to a cascade of psychological, behavioral, electrophysiological, immunological, endocrine, and genetic reactions in the body, primarily mediated by a sympathetic pathway. Conversely, mindfulness protects from deleterious effects of these triggered reactions by downregulating the HPA axis activity via a parasympathetic pathway. Finally, we propose a model suggesting a comprehensive scheme through which mindfulness and anxiety may interact through emotion regulation. It is recommended that future mindfulness intervention studies should examine a broad spectrum of measurement indices where possible, keeping logistic feasibility in mind and look at mindfulness in conjunction with anxiety rather than independently.

19.
Front Psychol ; 9: 1105, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29973902

RESUMO

[This corrects the article on p. 627 in vol. 9, PMID: 29780338.].

20.
Front Integr Neurosci ; 12: 17, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29867385

RESUMO

Prior studies have reported that meditation may improve cognitive functions and those related to attention in particular. Here, the dynamic process of attentional control, which allows subjects to focus attention on their current interests, was investigated. Concentrative meditation aims to cultivate the abilities of continuous focus and redirecting attention from distractions to the object of focus during meditation. However, it remains unclear how meditation may influence attentional reorientation, which involves interaction between both top-down and bottom-up processes. We aimed to investigate the modulating effect of meditation on the mechanisms of contingent reorienting by employing a rapid serial visual presentation (RSVP) task in conjunction with electrophysiological recording. We recruited 26 meditators who had an average of 2.9 years of meditation experience and a control group comprising 26 individuals without any prior experience of meditation. All subjects performed a 30-min meditation and a rest condition with data collected pre- and post-intervention, with each intervention given on different days. The state effect of meditation improved overall accuracy for all subjects irrespective of their group. A group difference was observed across interventions, showing that meditators were more accurate and more efficient at attentional suppression, represented by a larger Pd (distractor positive) amplitude of event related modes (ERMs), for target-like distractors than the control group. The findings suggested that better attentional control with respect to distractors might be facilitated by acquiring experience of and skills related to meditation training.

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