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1.
JMIR Mhealth Uhealth ; 11: e47371, 2023 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-37831493

RESUMO

BACKGROUND: Stress-related mental health disorders have steadily increased and contributed to a worldwide disease burden with up to 50% experiencing a stress-related mental health disorder worldwide. Data suggest that only approximately 20%-65% of individuals receive treatment. This gap in receiving treatment may be attributed to barriers such as limited treatment access, negative stigma surrounding mental health treatment, approachability (ie, not having a usual treatment plan or provider), affordability (ie, lack of insurance coverage and high treatment cost), and availability (ie, long waits for appointments) leaving those who need treatment without necessary care. To mitigate the limited access mental health treatment, there has been a rise in the application and study of digital mental health interventions. As such, there is an urgent need and opportunity for effective digital mental health interventions to alleviate stress symptoms, potentially reducing adverse outcomes of stress-related disorders. OBJECTIVE: This study examined if app-based guided mindfulness could improve subjective levels of stress and influence physiological markers of stress reactivity in a population with elevated symptoms of stress. METHODS: The study included 163 participants who had moderate to high perceived stress as assessed by the Perceived Stress Scale (PSS-10). Participants were randomly allocated to 1 of 5 groups: a digital guided program designed to alleviate stress (Managing Stress), a digital mindfulness fundamentals course (Basics), digitally delivered breathing exercises, an active control intervention (Audiobook), and a Waitlist Control group. The 3 formats of mindfulness interventions (Managing Stress, Basics, and Breathing) all had a total duration of 300 minutes spanning 20-30 days. Primary outcome measures were perceived stress using the PSS-10, self-reported sleep quality using the Pittsburgh Sleep Quality Index, and trait mindfulness using the Mindful Attention Awareness Scale. To probe the effects of physiological stress, an acute stress manipulation task was included, specifically the cold pressor task (CPT). Heart rate variability was collected before, during, and after exposure to the CPT and used as a measure of physiological stress. RESULTS: The results showed that PSS-10 and Pittsburgh Sleep Quality Index scores for the Managing Stress (all P<.001) and Basics (all P≤.002) groups were significantly reduced between preintervention and postintervention periods, while no significant differences were reported for the other groups. No significant differences among groups were reported for Mindful Attention Awareness Scale (P=.13). The physiological results revealed that the Managing Stress (P<.001) and Basics (P=.01) groups displayed reduced physiological stress reactivity between the preintervention and postintervention periods on the CPT. There were no significant differences reported for the other groups. CONCLUSIONS: These results demonstrate efficacy of app-based mindfulness in a population with moderate to high stress on improving self-reported stress, sleep quality, and physiological measures of stress during an acute stress manipulation task. TRIAL REGISTRATION: ClinicalTrials.gov NCT05832632; https://www.clinicaltrials.gov/ct2/show/NCT05832632.


Assuntos
Atenção Plena , Aplicativos Móveis , Humanos , Atenção Plena/métodos , Saúde Mental , Estresse Fisiológico , Agendamento de Consultas
2.
J Sci Med Sport ; 26(7): 375-385, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37301613

RESUMO

OBJECTIVES: To evaluate the effects of brain endurance training (BET) on endurance and cognitive performance in road cyclists. DESIGN: Two independent randomized controlled pretest-posttest training studies. METHODS: In both studies cyclists trained five times/week for six weeks and completed either cognitive response inhibition tasks (Post-BET group) or listened to neutral sounds (control group) after each training session. In Study-1, 26 cyclists performed a time to exhaustion (TTE) test at 80 % peak power output (PPO), followed by a 30-min Stroop task, and a TTE test at 65 % PPO. In Study-2, 24 cyclists performed a 5-min time trial, followed by a 30-min Stroop task, 60-min submaximal incremental test, and a 20-min . Heart rate, lactate, rating of perceived exertion (RPE), Stroop reaction time and accuracy were also measured. RESULTS: During Study 1, Post-BET improved TTE at 80 % (p = 0.032) and 65 % PPO (p = 0.011) significantly more than control with lower RPE (all p < 0.043). In Study 2, 5-min TT performance did not differ between groups. During the 60-min submaximal incremental test, RPE was lower in the Post-BET group compared to the control group (p = 0.034) and 20-min TT performance improved significantly more in the Post-BET group than in the control group (all p < 0.031). No group differences were found in physiological measures. In both studies, Stroop reaction times improved significantly more in the Post-BET group than in the control group (all p < 0.033). CONCLUSIONS: These findings suggest that Post-BET may be used to improve the performance of road cyclists.


Assuntos
Treino Aeróbico , Humanos , Ácido Láctico , Frequência Cardíaca/fisiologia , Cognição/fisiologia , Encéfalo , Ciclismo/fisiologia , Resistência Física/fisiologia , Consumo de Oxigênio/fisiologia
3.
4.
Int J Sports Physiol Perform ; 17(12): 1732-1740, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36370703

RESUMO

PURPOSE: Brain endurance training (BET)-the combination of physical training with mentally fatiguing tasks-could help athletes adapt and increase their performance during sporting competitions. Here we tested whether BET completed after standard physical training improved physical and mental performance more than physical training alone during a preseason football training camp. METHODS: The study employed a pretest/training/posttest design, with 22 professional football players randomly assigned to BET or a control group. Both groups completed 40 physical training sessions over 4 weeks. At the end of a day of physical training, the BET group completed cognitive training, whereas the control group listened to neutral sounds. Players completed the 30-15 Intermittent Fitness Test, repeated sprint ability random test, soccer-specific reactive agility test, and Stroop and psychomotor vigilance tests pretraining and posttraining. Mixed analysis of variance was used to analyze the data. RESULTS: In the posttest (but not pretest) assessments, the BET group consistently outperformed the control group. Specifically, the BET group was faster (P = .02-.04) than the control group during the 30-15 Intermittent Fitness Test, the directional phase of the repeated sprint ability random test, and the soccer-specific reactive agility test. The BET group also made fewer errors (P = .02) during the soccer-specific reactive agility test than the control group. Finally, the BET group responded faster (P = .02) on the Stroop test and made fewer (P = .03) lapses on the psychomotor vigilance test than the control group. CONCLUSION: The inclusion of BET during the preseason seems more effective than standard physical training alone in improving the physical, cognitive, and multitasking performance of professional football players.


Assuntos
Desempenho Atlético , Treino Aeróbico , Futebol , Humanos , Encéfalo , Cognição , Resistência Física
5.
Front Psychol ; 13: 915345, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36248509

RESUMO

In recent years, the possible benefits of mindfulness meditation have sparked much public and academic interest. Mindfulness emphasizes cultivating awareness of our immediate experience and has been associated with compassion, empathy, and various other prosocial traits. However, neurobiological evidence pertaining to the prosocial benefits of mindfulness in social settings is sparse. In this study, we investigate neural correlates of trait mindful awareness during naturalistic dyadic interactions, using both intra-brain and inter-brain measures. We used the Muse headset, a portable electroencephalogram (EEG) device often used to support mindfulness meditation, to record brain activity from dyads as they engaged in naturalistic face-to-face interactions in a museum setting. While we did not replicate prior laboratory-based findings linking trait mindfulness to individual brain responses (N = 379 individuals), self-reported mindful awareness did predict dyadic inter-brain synchrony, in theta (~5-8 Hz) and beta frequencies (~26-27 Hz; N = 62 dyads). These findings underscore the importance of conducting social neuroscience research in ecological settings to enrich our understanding of how (multi-brain) neural correlates of social traits such as mindful awareness manifest during social interaction, while raising critical practical considerations regarding the viability of commercially available EEG systems.

6.
BMC Psychol ; 10(1): 108, 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35478086

RESUMO

BACKGROUND: Occupational stress has huge financial as well as human costs. Application of crowdsourcing might be a way to strengthen the investigation of occupational mental health. Therefore, the aim of the study was to assess Danish employees' stress and cognition by relying on a crowdsourcing approach, as well as investigating the effect of a 30-day mindfulness and music intervention. METHODS: We translated well-validated neuropsychological laboratory- and task-based paradigms into an app-based platform using cognitive games measuring sustained attention and working memory and measuring stress via. Cohen's Perceived Stress Scale. A total of 623 healthy volunteers from Danish companies participated in the study and were randomized into three groups, which consisted of a 30-day intervention of either mindfulness or music, or a non-intervention control group. RESULTS: Participants in the mindfulness group showed a significant improvement in the coefficient of sustained attention, working memory capacity and perceived stress (p < .001). The music group showed a 38% decrease of self-perceived stress. The control group showed no difference from pre to post in the survey or cognitive outcome measures. Furthermore, there was a significant correlation between usage of the mindfulness and music app and elevated score on both the cognitive games and the perceived stress scale. CONCLUSION: The study supports the nascent field of crowdsourcing by being able to replicate data collected in previous well-controlled laboratory studies from a range of experimental cognitive tasks, making it an effective alternative. It also supports mindfulness as an effective intervention in improving mental health in the workplace.


Assuntos
Crowdsourcing , Meditação , Atenção Plena , Musicoterapia , Música , Atenção , Humanos , Memória de Curto Prazo , Estresse Psicológico/psicologia
7.
PLoS One ; 15(12): e0243488, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33332403

RESUMO

OBJECTIVES: The goal of the present study was to probe the effects of mindfulness practice in a naturalistic setting as opposed to a lab-based environment in the presence of continuous heart rate variability (HRV) measurements. The specific experimental goals were to examine the effects of a brief 10-day online-based mindfulness intervention on both chronic and acute HRV responses. METHOD: We conducted a fully randomized 10-day longitudinal trial of mindfulness practice, explicitly controlling for practice effects with an active-control group (music listening) and a non-intervention control group. To assess chronic cardiovascular effects, we asked participants in the 3 groups to complete 2-day HRV pre- and post-intervention measurement sessions. Using this experimental setup enabled us to address training effects arising from mindfulness practice to assess physiological impact on daytime as well as nighttime (i.e. assessing sleep quality) on the underlying HRV response. To assess acute cardiovascular effects, we measured HRV in the 2 active intervention groups during each of the 10 daily mindfulness or music sessions. This allowed us to track the development of purported training effects arising from mindfulness practice relative to the active-control intervention in terms of changes in the HRV slope over the 10-day time-course. RESULTS: Firstly, for the acute phase we found increased HRV during the daily practice sessions in both the mindfulness and active-control group indicating that both interventions were effective in decreasing acute physiological stress. Secondly, for the chronic phase we found increased HRV in both the day- and nighttime indicating increased sleep quality, specifically in the mindfulness group. CONCLUSION: These results suggest causal effects in both chronic and acute phases of mindfulness practice in formerly naïve subjects and provides support for the argument that brief online-based mindfulness interventions exert positive impact on HRV.


Assuntos
Frequência Cardíaca/fisiologia , Atenção Plena/métodos , Doença Aguda , Adulto , Doenças Cardiovasculares/patologia , Doença Crônica , Eletrofisiologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Música , Processamento de Sinais Assistido por Computador , Sono/fisiologia , Estresse Psicológico
8.
Brain Behav ; 10(9): e01761, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32749046

RESUMO

INTRODUCTION: In this study, we show new evidence for the role of ventrolateral prefrontal cortex-dorsolateral prefrontal cortex (VLPFC-DLPFC) networks in the cognitive framing of emotional processing. METHOD: We displayed neutral and aversive images described as having been sourced from artistic material to one cohort of subjects (i.e., the art-frame group; n = 19), while identical images, this time identified as having been sourced from documentary material (i.e., the doc-frame group; n = 20) were shown to a separate cohort. RESULTS: Using functional magnetic resonance imaging (fMRI), we employed a linear parametric model showing that relative to the doc-frame group the art-frame group exhibited a modulation of amygdala activity in response to aversive images. The attenuated amygdala activity in the art-frame group supported our hypothesis that reduced amygdala activity was driven by top-down DLPFC inhibition of limbic responses. A psychophysiological interaction (PPI) analysis demonstrated that VLPFC activity correlated with amygdala activity in the art-frame group, but not in the doc-frame group for the contrast [Aversive > Neutral]. CONCLUSION: The role of the VLPFC in cognitive control suggests the hypothesis that it alongside DLPFC insulates against embodied emotional responses by inhibiting automatic affective responses.


Assuntos
Imageamento por Ressonância Magnética , Córtex Pré-Frontal , Tonsila do Cerebelo/diagnóstico por imagem , Mapeamento Encefálico , Cognição , Emoções , Humanos , Córtex Pré-Frontal/diagnóstico por imagem
9.
Hum Brain Mapp ; 41(7): 1950-1967, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31872943

RESUMO

Understanding and reducing variability of response to transcranial direct current stimulation (tDCS) requires measuring what factors predetermine sensitivity to tDCS and tracking individual response to tDCS. Human trials, animal models, and computational models suggest structural traits and functional states of neural systems are the major sources of this variance. There are 118 published tDCS studies (up to October 1, 2018) that used fMRI as a proxy measure of neural activation to answer mechanistic, predictive, and localization questions about how brain activity is modulated by tDCS. FMRI can potentially contribute as: a measure of cognitive state-level variance in baseline brain activation before tDCS; inform the design of stimulation montages that aim to target functional networks during specific tasks; and act as an outcome measure of functional response to tDCS. In this systematic review, we explore methodological parameter space of tDCS integration with fMRI spanning: (a) fMRI timing relative to tDCS (pre, post, concurrent); (b) study design (parallel, crossover); (c) control condition (sham, active control); (d) number of tDCS sessions; (e) number of follow up scans; (f) stimulation dose and combination with task; (g) functional imaging sequence (BOLD, ASL, resting); and (h) additional behavioral (cognitive, clinical) or quantitative (neurophysiological, biomarker) measurements. Existing tDCS-fMRI literature shows little replication across these permutations; few studies used comparable study designs. Here, we use a representative sample study with both task and resting state fMRI before and after tDCS in a crossover design to discuss methodological confounds. We further outline how computational models of current flow should be combined with imaging data to understand sources of variability. Through the representative sample study, we demonstrate how modeling and imaging methodology can be integrated for individualized analysis. Finally, we discuss the importance of conducting tDCS-fMRI with stimulation equipment certified as safe to use inside the MR scanner, and of correcting for image artifacts caused by tDCS. tDCS-fMRI can address important questions on the functional mechanisms of tDCS action (e.g., target engagement) and has the potential to support enhancement of behavioral interventions, provided studies are designed rationally.


Assuntos
Imageamento por Ressonância Magnética/métodos , Estimulação Transcraniana por Corrente Contínua/métodos , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Cognição/fisiologia , Humanos , Desempenho Psicomotor/fisiologia
10.
Sci Rep ; 9(1): 19896, 2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31882606

RESUMO

Anxiety and trauma related disorders are highly prevalent, causing suffering and high costs for society. Current treatment strategies, although effective, only show moderate effect-sizes when compared to adequate control groups demonstrating a need to develop new forms of treatment or optimize existing ones. In order to achieve this, an increased understanding of what mechanisms are involved is needed. An emerging literature indicates that mindfulness training (MFT) can be used to treat fear and anxiety related disorders, but the treatment mechanisms are unclear. One hypothesis, largely based on findings from neuroimaging studies, states that MFT may improve extinction retention, but this has not been demonstrated empirically. To investigate this question healthy subjects either completed a 4-week MFT- intervention delivered through a smart-phone app (n = 14) or were assigned to a waitlist (n = 15). Subsequently, subjects participated in a two-day experimental protocol using pavlovian aversive conditioning, evaluating acquisition and extinction of threat-related responses on day 1, and extinction retention on day 2. Results showed that the MFT group displayed reduced spontaneous recovery of threat related arousal responses, as compared to the waitlist control group, on day 2. MFT did not however, have an effect on either the acquisition or extinction of conditioned responses day 1. This clarifies the positive effect of MFT on emotional functioning and could have implications for the treatment of anxiety and trauma related disorders.


Assuntos
Condicionamento Psicológico , Extinção Psicológica , Medo/psicologia , Atenção Plena , Adolescente , Adulto , Idoso , Ansiedade/fisiopatologia , Ansiedade/psicologia , Ansiedade/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ferimentos e Lesões/fisiopatologia , Ferimentos e Lesões/psicologia , Ferimentos e Lesões/terapia
11.
Sci Rep ; 9(1): 6964, 2019 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-31061515

RESUMO

Activity changes in dopaminergic neurons encode the ongoing discrepancy between expected and actual value of a stimulus, providing a teaching signal for a reward prediction process. Previous work comparing a cohort of long-term Zen meditators to controls demonstrated an attenuation of reward prediction signals to appetitive reward in the striatum. Using a cross-commodity design encompassing primary- and secondary-reward conditioning experiments, the present study asks the question of whether reward prediction signals are causally altered by mindfulness training in naïve subjects. Volunteers were randomly assigned to 8 weeks of mindfulness training (MT), active control training (CT), or a one-time mindfulness induction group (MI). We observed a decreased response to positive prediction errors in the putamen in the MT group compared to CT using both a primary and a secondary-reward experiment. Furthermore, the posterior insula showed greater activation to primary rewards, independently of their predictability, in the MT group, relative to CT and MI group. These results support the notion that increased attention to the present moment and its interoceptive features - a core component of mindfulness practice - may reduce predictability effects in reward processing, without dampening (in fact, enhancing) the response to the actual delivery of the stimulus.


Assuntos
Antecipação Psicológica/fisiologia , Atenção/fisiologia , Encéfalo/fisiologia , Meditação/métodos , Atenção Plena/métodos , Recompensa , Humanos , Estudos Longitudinais
12.
Front Psychiatry ; 7: 126, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27468271

RESUMO

Little is known about the specific neural mechanisms through which cognitive factors influence craving and associated brain responses, despite the initial success of cognitive therapies in treating drug addiction. In this study, we investigated how cognitive factors such as beliefs influence subjective craving and neural activities in nicotine-addicted individuals using model-based functional magnetic resonance imaging (fMRI) and neuropharmacology. Deprived smokers (N = 24) participated in a two-by-two balanced placebo design, which crossed beliefs about nicotine (told "nicotine" vs. told "no nicotine") with the nicotine content in a cigarette (nicotine vs. placebo) which participants smoked immediately before performing a fMRI task involving reward learning. Subjects' reported craving was measured both before smoking and after the fMRI session. We found that first, in the presence of nicotine, smokers demonstrated significantly reduced craving after smoking when told "nicotine in cigarette" but showed no change in craving when told "no nicotine." Second, neural activity in the insular cortex related to craving was only significant when smokers were told "nicotine" but not when told "no nicotine." Both effects were absent in the placebo condition. Third, insula activation related to computational learning signals was modulated by belief about nicotine regardless of nicotine's presence. These results suggest that belief about nicotine has a strong impact on subjective craving and insula responses related to both craving and learning in deprived smokers, providing insights into the complex nature of belief-drug interactions.

13.
Neuroimage ; 138: 274-283, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27266443

RESUMO

Emotions have been shown to exert influences on decision making during economic exchanges. Here we investigate the underlying neural mechanisms of a training regimen which is hypothesized to promote emotional awareness, specifically mindfulness training (MT). We test the hypothesis that MT increases cooperative economic decision making using fMRI in a randomized longitudinal design involving 8weeks of either MT or active control training (CT). We find that MT results in an increased willingness to cooperate indexed by higher acceptance rates to unfair monetary offers in the Ultimatum Game. While controlling for acceptance rates of monetary offers between intervention groups, subjects in the MT and CT groups show differential brain activation patterns. Specifically, a subset of more cooperative MT subjects displays increased activation in the septal region, an area linked to social attachment, which may drive the increased willingness to express cooperative behavior in the MT cohort. Furthermore, MT resulted in attenuated activity in anterior insula compared with the CT group in response to unfair monetary offers post-training, which may suggest that MT enables greater ability to effectively regulate the anterior insula and thereby promotes social cooperation. Finally, functional connectivity analyses show a coupling between the septal region and posterior insula in the MT group, suggesting an integration of interoceptive inputs. Together, these results highlight that MT may be employed in contexts where emotional regulation is required to promote social cooperation.


Assuntos
Altruísmo , Conscientização/fisiologia , Córtex Cerebral/fisiologia , Tomada de Decisões/fisiologia , Emoções/fisiologia , Atenção Plena/métodos , Adulto , Mapeamento Encefálico/métodos , Economia Comportamental , Feminino , Jogos Experimentais , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Rede Nervosa/fisiologia , Resultado do Tratamento
14.
Front Psychol ; 6: 90, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25729372

RESUMO

Reinforcement learning models have demonstrated that phasic activity of dopamine neurons during reward expectation encodes information about the predictability of reward and cues that predict reward. Self-control strategies such as those practiced in mindfulness-based approaches is claimed to reduce negative and positive reactions to stimuli suggesting the hypothesis that such training may influence basic reward processing. Using a passive conditioning task and fMRI in a group of experienced mindfulness meditators and age-matched controls, we tested the hypothesis that mindfulness meditation influence reward and reward prediction error (PE) signals. We found diminished positive and negative PE-related blood-oxygen level-dependent (BOLD) responses in the putamen in meditators compared with controls. In the meditator group this decrease in striatal BOLD responses to reward PE was paralleled by increased activity in posterior insula, a primary interoceptive region. Critically, responses in the putamen during early trials of the conditioning procedure (run 1) were elevated in both meditators and controls. Overall, these results provide evidence that experienced mindfulness meditators are able to attenuate reward prediction signals to valenced stimuli, which may be related to interoceptive processes encoded in the posterior insula.

15.
Proc Natl Acad Sci U S A ; 112(8): 2539-44, 2015 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-25605923

RESUMO

Little is known about how prior beliefs impact biophysically described processes in the presence of neuroactive drugs, which presents a profound challenge to the understanding of the mechanisms and treatments of addiction. We engineered smokers' prior beliefs about the presence of nicotine in a cigarette smoked before a functional magnetic resonance imaging session where subjects carried out a sequential choice task. Using a model-based approach, we show that smokers' beliefs about nicotine specifically modulated learning signals (value and reward prediction error) defined by a computational model of mesolimbic dopamine systems. Belief of "no nicotine in cigarette" (compared with "nicotine in cigarette") strongly diminished neural responses in the striatum to value and reward prediction errors and reduced the impact of both on smokers' choices. These effects of belief could not be explained by global changes in visual attention and were specific to value and reward prediction errors. Thus, by modulating the expression of computationally explicit signals important for valuation and choice, beliefs can override the physical presence of a potent neuroactive compound like nicotine. These selective effects of belief demonstrate that belief can modulate model-based parameters important for learning. The implications of these findings may be far ranging because belief-dependent effects on learning signals could impact a host of other behaviors in addiction as well as in other mental health problems.


Assuntos
Cultura , Nicotina/farmacologia , Recompensa , Fumar/efeitos adversos , Adulto , Atenção/fisiologia , Comportamento de Escolha/efeitos dos fármacos , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Placebos , Percepção Visual/efeitos dos fármacos
16.
Soc Cogn Affect Neurosci ; 10(5): 752-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25193949

RESUMO

Reward seeking is ubiquitous and adaptive in humans. But excessive reward seeking behavior, such as chasing monetary rewards, may lead to diminished subjective well-being. This study examined whether individuals trained in mindfulness meditation show neural evidence of lower susceptibility to monetary rewards. Seventy-eight participants (34 meditators, 44 matched controls) completed the monetary incentive delay task while undergoing functional magnetic resonance imaging. The groups performed equally on the task, but meditators showed lower neural activations in the caudate nucleus during reward anticipation, and elevated bilateral posterior insula activation during reward anticipation. Meditators also evidenced reduced activations in the ventromedial prefrontal cortex during reward receipt compared with controls. Connectivity parameters between the right caudate and bilateral anterior insula were attenuated in meditators during incentive anticipation. In summary, brain regions involved in reward processing-both during reward anticipation and receipt of reward-responded differently in mindfulness meditators than in nonmeditators, indicating that the former are less susceptible to monetary incentives.


Assuntos
Adaptação Psicológica/fisiologia , Antecipação Psicológica/fisiologia , Atenção Plena , Recompensa , Adulto , Mapeamento Encefálico , Feminino , Humanos , Individualidade , Imageamento por Ressonância Magnética , Masculino , Meditação/psicologia , Motivação , Vias Neurais/fisiologia , Adulto Jovem
17.
Neuroimage ; 100: 254-62, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24956066

RESUMO

Neuroimaging research has demonstrated that ventromedial prefrontal cortex (vmPFC) encodes value signals that can be modulated by top-down cognitive input such as semantic knowledge, price incentives, and monetary favors suggesting that such biases may have an identified biological basis. It has been hypothesized that mindfulness training (MT) provides one path for gaining control over such top-down influences; yet, there have been no direct tests of this hypothesis. Here, we probe the behavioral and neural effects of MT on value signals in vmPFC in a randomized longitudinal design of 8 weeks of MT on an initially naïve subject cohort. The impact of this within-subject training was assessed using two paradigms: one that employed primary rewards (fruit juice) in a simple conditioning task and another that used a well-validated art-viewing paradigm to test bias of monetary favors on preference. We show that MT behaviorally censors the top-down bias of monetary favors through a measurable influence on value signals in vmPFC. MT also modulates value signals in vmPFC to primary reward delivery. Using a separate cohort of subjects we show that 8 weeks of active control training (ACT) generates the same behavioral impact also through an effect on signals in the vmPFC. Importantly, functional connectivity analyses show that value signals in vmPFC are coupled with bilateral posterior insula in the MT groups in both paradigms, but not in the ACT groups. These results suggest that MT integrates interoceptive input from insular cortex in the context of value computations of both primary and secondary rewards.


Assuntos
Mapeamento Encefálico/métodos , Córtex Cerebral/fisiologia , Interocepção/fisiologia , Atenção Plena , Córtex Pré-Frontal/fisiologia , Recompensa , Adulto , Feminino , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Atenção Plena/métodos , Adulto Jovem
18.
Hum Brain Mapp ; 35(8): 3738-49, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24382784

RESUMO

Computational models of reward processing suggest that foregone or fictive outcomes serve as important information sources for learning and augment those generated by experienced rewards (e.g. reward prediction errors). An outstanding question is how these learning signals interact with top-down cognitive influences, such as cognitive reappraisal strategies. Using a sequential investment task and functional magnetic resonance imaging, we show that the reappraisal strategy selectively attenuates the influence of fictive, but not reward prediction error signals on investment behavior; such behavioral effect is accompanied by changes in neural activity and connectivity in the anterior insular cortex, a brain region thought to integrate subjective feelings with high-order cognition. Furthermore, individuals differ in the extent to which their behaviors are driven by fictive errors versus reward prediction errors, and the reappraisal strategy interacts with such individual differences; a finding also accompanied by distinct underlying neural mechanisms. These findings suggest that the variable interaction of cognitive strategies with two important classes of computational learning signals (fictive, reward prediction error) represent one contributing substrate for the variable capacity of individuals to control their behavior based on foregone rewards. These findings also expose important possibilities for understanding the lack of control in addiction based on possibly foregone rewarding outcomes.


Assuntos
Encéfalo/fisiologia , Cognição/fisiologia , Tomada de Decisões , Investimentos em Saúde , Recompensa , Adulto , Antecipação Psicológica/fisiologia , Mapeamento Encefálico , Feminino , Humanos , Aprendizagem/fisiologia , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/fisiologia , Testes Neuropsicológicos , Psicofísica , Análise de Regressão
19.
Proc Natl Acad Sci U S A ; 108(25): 10332-6, 2011 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-21646526

RESUMO

Recent work using an art-viewing paradigm shows that monetary sponsorship of the experiment by a company (a favor) increases the valuation of paintings placed next to the sponsoring corporate logo, an effect that correlates with modulation of the ventromedial prefrontal cortex (VMPFC). We used the same art-viewing paradigm to test a prevailing idea in the domain of conflict-of-interest: that expertise in a domain insulates against judgment bias even in the presence of a monetary favor. Using a cohort of art experts, we show that monetary favors do not bias the experts' valuation of art, an effect that correlates with a lack of modulation of the VMPFC across sponsorship conditions. The lack of sponsorship effect in the VMPFC suggests the hypothesis that their brains remove the behavioral sponsorship effect by censoring sponsorship-dependent modulation of VMPFC activity. We tested the hypothesis that prefrontal regions play a regulatory role in mediating the sponsorship effect. We show that the dorsolateral prefrontal cortex (DLPFC) is recruited in the expert group. Furthermore, we tested the hypothesis in nonexpert controls by contrasting brain responses in controls who did not show a sponsorship effect to controls who did. Changes in effective connectivity between the DLPFC and VMPFC were greater in nonexpert controls, with an absence of the sponsorship effect relative to those with a presence of the sponsorship effect. The role of the DLPFC in cognitive control and emotion regulation suggests that it removes the influence of a monetary favor by controlling responses in known valuation regions of the brain including the the VMPFC.


Assuntos
Viés , Comportamento de Escolha/fisiologia , Julgamento/fisiologia , Córtex Pré-Frontal/anatomia & histologia , Córtex Pré-Frontal/fisiologia , Recompensa , Adolescente , Adulto , Arte , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Adulto Jovem
20.
Front Neurosci ; 5: 49, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21559066

RESUMO

Human decision-making is often conceptualized as a competition between cognitive and emotional processes in the brain. Deviations from rational processes are believed to derive from inclusion of emotional factors in decision-making. Here, we investigate whether experienced Buddhist meditators are better equipped to regulate emotional processes compared with controls during economic decision-making in the Ultimatum Game. We show that meditators accept unfair offers on more than half of the trials, whereas controls only accept unfair offers on one-quarter of the trials. By applying fMRI we show that controls recruit the anterior insula during unfair offers. Such responses are powerful predictors of rejecting offers in social interaction. By contrast, meditators display attenuated activity in high-level emotional representations of the anterior insula and increased activity in the low-level interoceptive representations of the posterior insula. In addition we show that a subset of control participants who play rationally (i.e., accepts >85% unfair offers) recruits the dorsolateral prefrontal cortex presumably reflecting increased cognitive demands, whereas rational meditators by contrast display elevated activity in the somatosensory cortex and posterior superior temporal cortex. In summary, when assessing unfairness in the Ultimatum Game, meditators activate a different network of brain areas compared with controls enabling them to uncouple negative emotional reactions from their behavior. These findings highlight the clinically and socially important possibility that sustained training in mindfulness meditation may impact distinct domains of human decision-making.

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