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1.
Hum Brain Mapp ; 45(8): e26716, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38798117

RESUMO

Acute psychosocial stress affects learning, memory, and attention, but the evidence for the influence of stress on the neural processes supporting cognitive control remains mixed. We investigated how acute psychosocial stress influences performance and neural processing during the Go/NoGo task-an established cognitive control task. The experimental group underwent the Trier Social Stress Test (TSST) acute stress induction, whereas the control group completed personality questionnaires. Then, participants completed a functional magnetic resonance imaging (fMRI) Go/NoGo task, with self-report, blood pressure and salivary cortisol measurements of induced stress taken intermittently throughout the experimental session. The TSST was successful in eliciting a stress response, as indicated by significant Stress > Control between-group differences in subjective stress ratings and systolic blood pressure. We did not identify significant differences in cortisol levels, however. The stress induction also impacted subsequent Go/NoGo task performance, with participants who underwent the TSST making fewer commission errors on trials requiring the most inhibitory control (NoGo Green) relative to the control group, suggesting increased vigilance. Univariate analysis of fMRI task-evoked brain activity revealed no differences between stress and control groups for any region. However, using multivariate pattern analysis, stress and control groups were reliably differentiated by activation patterns contrasting the most demanding NoGo trials (i.e., NoGo Green trials) versus baseline in the medial intraparietal area (mIPA, affiliated with the dorsal attention network) and subregions of the cerebellum (affiliated with the default mode network). These results align with prior reports linking the mIPA and the cerebellum to visuomotor coordination, a function central to cognitive control processes underlying goal-directed behavior. This suggests that stressor-induced hypervigilance may produce a facilitative effect on response inhibition which is represented neurally by the activation patterns of cognitive control regions.


Assuntos
Inibição Psicológica , Imageamento por Ressonância Magnética , Estresse Psicológico , Humanos , Estresse Psicológico/fisiopatologia , Estresse Psicológico/diagnóstico por imagem , Masculino , Feminino , Adulto , Adulto Jovem , Função Executiva/fisiologia , Hidrocortisona/metabolismo , Desempenho Psicomotor/fisiologia
2.
Learn Mem ; 29(1): 16-28, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34911800

RESUMO

It has been suggested that there are two distinct and parallel mechanisms for controlling instrumental behavior in mammals: goal-directed actions and habits. To gain an understanding of how these two systems interact to control behavior, it is essential to characterize the mechanisms by which the balance between these systems is influenced by experience. Studies in rodents have shown that the amount of training governs the relative expression of these two systems: Behavior is goal-directed following moderate training, but the more extensively an instrumental action is trained, the more it becomes habitual. It is less clear whether humans exhibit similar training effects on the expression of goal-directed and habitual behavior, as human studies have reported contradictory findings. To tackle these contradictory findings, we formed a consortium, where four laboratories undertook a preregistered experimental induction of habits by manipulating the amount of training. There was no statistical evidence for a main effect of the amount of training on the formation and expression of habits. However, exploratory analyses suggest a moderating effect of the affective component of stress on the impact of training over habit expression. Participants who were lower in affective stress appeared to be initially goal-directed, but became habitual with increased training, whereas participants who were high in affective stress were already habitual even after moderate training, thereby manifesting insensitivity to overtraining effects. Our findings highlight the importance of the role of moderating variables such as individual differences in stress and anxiety when studying the experimental induction of habits in humans.


Assuntos
Condicionamento Operante , Objetivos , Animais , Hábitos , Humanos , Motivação
3.
Neuroimage ; 147: 330-338, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-27989778

RESUMO

Effort discounting theory suggests that the value of a reward should be lower if it was effortful to obtain, whereas contrast theory suggests that the contrast between the costly effort and the reward makes the reward seem more valuable. To test these alternative hypotheses, we used functional magnetic resonance imaging (fMRI) as participants engaged in feedback-based learning that required low or high cognitive effort to obtain positive feedback, while the objective amount of information provided by feedback remained constant. In the low effort condition, a single image was presented with four response options. In the high effort condition, two images were presented, each with two response options, and correct feedback was presented only when participants responded correctly to both of the images. Accuracy was significantly lower for the high effort condition, and all participants reported that the high effort condition was more difficult. A region of the ventral striatum selected for sensitivity to feedback value also showed increased activation to feedback presentation associated with the high effort condition relative to the low effort condition, when controlling for activation from corresponding control conditions where feedback was random. These results suggest that increased cognitive effort produces corresponding increases in positive feedback-related ventral striatum activity, in line with the predictions made by contrast theory. The accomplishment of obtaining a hard-earned intrinsic reward, such as positive feedback, may be particularly likely to promote reward-related brain activity.


Assuntos
Mapeamento Encefálico/métodos , Retroalimentação Psicológica/fisiologia , Aprendizagem/fisiologia , Córtex Pré-Frontal/fisiologia , Desempenho Psicomotor/fisiologia , Estriado Ventral/fisiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Estriado Ventral/diagnóstico por imagem , Adulto Jovem
4.
Hum Brain Mapp ; 38(1): 457-471, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27622781

RESUMO

In our fMRI experiment, participants completed a learning task in both a noncompetitive and a socially competitive learning environment. Despite reporting a preference for completing the task while competing, participants remembered significantly more during the task and later recalled more from the noncompetitive learning environment. Furthermore, during working memory maintenance, there was performance-related deactivation in the medial prefrontal cortex (mPFC) and the precuneus/PCC. During feedback presentation, there was greater activation in the mPFC and the precuneus/PCC while competing. Differential activation in the precuneus/PCC predicted worse later recall for information learned competitively. Since previous research suggests that the mPFC is involved in social-referencing, while the precuneus/PCC is implicated in off-task thoughts, our results suggest that receiving feedback regarding competition produces more activation in brain regions implicated in social interaction, as well as task distraction. While competition may make a task more enjoyable, the goal of winning may distract from maximizing performance. Hum Brain Mapp 38:457-471, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiologia , Memória de Curto Prazo/fisiologia , Rememoração Mental/fisiologia , Habilidades Sociais , Adolescente , Adulto , Aprendizagem por Associação/fisiologia , Atitude , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Oxigênio/sangue , Adulto Jovem
5.
J Cogn Neurosci ; 28(2): 261-74, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26439265

RESUMO

Whereas positive feedback is both rewarding and informative, negative feedback can be construed as either punishing (because it is indicative of poor performance) or informative (because it may lead to goal attainment). In this neuroimaging experiment, we highlighted the informational value of negative feedback by intermixing trials with and without feedback. When performance feedback is expected, positive feedback triggers an increase in striatal activity, whereas negative feedback elicits a decrease in striatal activity. We predicted that, in contrast, when feedback receipt is unpredictable, the striatal response to negative feedback would increase. Participants performed a paired-associate learning task during fMRI scanning. In one condition ("blocked feedback"), the receipt of feedback was predictable--participants knew whether or not they would receive feedback for their responses. In another condition ("mixed feedback"), the receipt of feedback was unpredictable--on a random 50% of trials, participants received feedback, and they otherwise received no feedback. Negative feedback in the mixed feedback condition elicited more striatal activity than negative feedback in the blocked feedback condition. In contrast, feedback omission evoked more striatal activity when feedback delivery was expected, compared to when it was unpredictable. This pattern emerged from an increase in caudate activity in response to negative feedback in the mixed feedback condition and a decrease in ventral striatal activity in response to no feedback in this condition. These results suggest that, by emphasizing the informational value of negative feedback, an unpredictable feedback context alters the striatal response to negative feedback and to the omission of feedback.


Assuntos
Antecipação Psicológica/fisiologia , Aprendizagem por Associação/fisiologia , Retroalimentação Psicológica/fisiologia , Neostriado/fisiologia , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Reconhecimento Visual de Modelos/fisiologia , Adulto Jovem
6.
Nature ; 463(7284): 1089-91, 2010 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-20182511

RESUMO

A popular hypothesis in the social sciences is that humans have social preferences to reduce inequality in outcome distributions because it has a negative impact on their experienced reward. Although there is a large body of behavioural and anthropological evidence consistent with the predictions of these theories, there is no direct neural evidence for the existence of inequality-averse preferences. Such evidence would be especially useful because some behaviours that are consistent with a dislike for unequal outcomes could also be explained by concerns for social image or reciprocity, which do not require a direct aversion towards inequality. Here we use functional MRI to test directly for the existence of inequality-averse social preferences in the human brain. Inequality was created by recruiting pairs of subjects and giving one of them a large monetary endowment. While both subjects evaluated further monetary transfers from the experimenter to themselves and to the other participant, we measured neural responses in the ventral striatum and ventromedial prefrontal cortex, two areas that have been shown to be involved in the valuation of monetary and primary rewards in both social and non-social contexts. Consistent with inequality-averse models of social preferences, we find that activity in these areas was more responsive to transfers to others than to self in the 'high-pay' subject, whereas the activity of the 'low-pay' subject showed the opposite pattern. These results provide direct evidence for the validity of this class of models, and also show that the brain's reward circuitry is sensitive to both advantageous and disadvantageous inequality.


Assuntos
Modelos Neurológicos , Recompensa , Comportamento Social , Justiça Social/economia , Justiça Social/psicologia , Gânglios da Base/fisiologia , Beneficência , Humanos , Imageamento por Ressonância Magnética , Masculino , Córtex Pré-Frontal/anatomia & histologia , Córtex Pré-Frontal/fisiologia , Reprodutibilidade dos Testes , Desempenho de Papéis , Adulto Jovem
7.
Neuroimage ; 119: 175-86, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26112370

RESUMO

Learning commonly requires feedback about the consequences of one's actions, which can drive learners to modify their behavior. Motivation may determine how sensitive an individual might be to such feedback, particularly in educational contexts where some students value academic achievement more than others. Thus, motivation for a task might influence the value placed on performance feedback and how effectively it is used to improve learning. To investigate the interplay between intrinsic motivation and feedback processing, we used functional magnetic resonance imaging (fMRI) during feedback-based learning before and after a novel manipulation based on motivational interviewing, a technique for enhancing treatment motivation in mental health settings. Because of its role in the reinforcement learning system, the striatum is situated to play a significant role in the modulation of learning based on motivation. Consistent with this idea, motivation levels during the task were associated with sensitivity to positive versus negative feedback in the striatum. Additionally, heightened motivation following a brief motivational interview was associated with increases in feedback sensitivity in the left medial temporal lobe. Our results suggest that motivation modulates neural responses to performance-related feedback, and furthermore that changes in motivation facilitate processing in areas that support learning and memory.


Assuntos
Corpo Estriado/fisiologia , Feedback Formativo , Aprendizagem/fisiologia , Motivação/fisiologia , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
8.
J Neurophysiol ; 113(1): 4-13, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25339705

RESUMO

For the consequences of our actions to guide behavior, the brain must represent different types of outcome-related information. For example, an outcome can be construed as negative because an expected reward was not delivered or because an outcome of low value was delivered. Thus behavioral consequences can differ in terms of the information they provide about outcome probability and value. We investigated the role of the striatum in processing probability-based and value-based negative feedback by training participants to associate cues with food rewards and then employing a selective satiety procedure to devalue one food outcome. Using functional magnetic resonance imaging, we examined brain activity related to receipt of expected rewards, receipt of devalued outcomes, omission of expected rewards, omission of devalued outcomes, and expected omissions of an outcome. Nucleus accumbens activation was greater for rewarding outcomes than devalued outcomes, but activity in this region did not correlate with the probability of reward receipt. Activation of the right caudate and putamen, however, was largest in response to rewarding outcomes relative to expected omissions of reward. The dorsal striatum (caudate and putamen) at the time of feedback also showed a parametric increase correlating with the trialwise probability of reward receipt. Our results suggest that the ventral striatum is sensitive to the motivational relevance, or subjective value, of the outcome, while the dorsal striatum codes for a more complex signal that incorporates reward probability. Value and probability information may be integrated in the dorsal striatum, to facilitate action planning and allocation of effort.


Assuntos
Corpo Estriado/fisiologia , Retroalimentação Psicológica/fisiologia , Probabilidade , Recompensa , Antecipação Psicológica/fisiologia , Mapeamento Encefálico , Sinais (Psicologia) , Feminino , Alimentos , Preferências Alimentares , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Adulto Jovem
9.
Cogn Affect Behav Neurosci ; 14(2): 610-20, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24638235

RESUMO

The striatum plays a critical role in learning from reward, and it has been implicated in learning from performance-related feedback as well. Positive and negative performance-related feedback is known to engage the striatum during learning by eliciting a response similar to the reinforcement signal for extrinsic rewards and punishments. Feedback is an important tool used to teach new skills and promote healthful lifestyle changes, so it is important to understand how motivational contexts can modulate its effectiveness at promoting learning. While it is known that striatal responses scale with subjective factors influencing the desirability of rewards, it is less clear how expectations and goals might modulate the striatal responses to cognitive feedback during learning. We used functional magnetic resonance imaging to investigate the effects of task difficulty expectations and achievement goals on feedback processing during learning. We found that individuals who scored high in normative goals, which reflect a desire to outperform other students academically, showed the strongest effects of our manipulation. High levels of normative goals were associated with greater performance gains and exaggerated striatal sensitivity to positive versus negative feedback during blocks that were expected to be more difficult. Our findings suggest that normative goals may enhance performance when difficulty expectations are high, while at the same time modulating the subjective value of feedback as processed in the striatum.


Assuntos
Corpo Estriado/fisiologia , Retroalimentação Fisiológica/fisiologia , Objetivos , Aprendizagem/fisiologia , Motivação/fisiologia , Percepção Visual/fisiologia , Adolescente , Adulto , Análise de Variância , Corpo Estriado/irrigação sanguínea , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Oxigênio/sangue , Estimulação Luminosa , Inquéritos e Questionários , Adulto Jovem
10.
Front Psychol ; 15: 1224451, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38390411

RESUMO

Planfulness refers to an individual's tendency to be future oriented, mentally flexible, and cognitively strategic when engaging with goals, and has been shown to predict goal completion. We investigated the relationships among planfulness, goal disruption, stress, and psychological well-being during the COVID-19 pandemic, which served as a unique setback context. We measured these constructs using the planfulness scale, an ad-hoc survey item probing goal disruption in the pandemic, the perceived stress scale, and the Warwick-Edinburgh Mental Wellbeing Scale, respectively. Participants were university students (N = 174; mean age 23.03, SD: 4.37; 77% female). Higher planfulness predicted lower goal-disruption, lower stress, and higher well-being during the pandemic, extending its benefits beyond the goal domain. High levels of planfulness did not protect against goal disruption among those participants in which the self-reported personal impact of the pandemic was highest. Differences in goal disruption across levels of planfulness were constrained to lower reported pandemic impact. However, the differences in psychological well-being and stress by levels of planfulness were retained even when self-reported perceptions of personal pandemic impact were high. More planful students maintained lower stress and higher psychological well-being than their less planful peers across levels of adversity. These findings suggest that even in extremely difficult contexts in which planfulness does not protect against goal disruption, it still confers personal benefits in terms of psychological health.

11.
Cogn Affect Behav Neurosci ; 13(4): 725-36, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23817894

RESUMO

The striatum has been shown to play an important role in learning from performance-related feedback that is presented shortly after each response. However, less is known about the neural mechanisms supporting learning from feedback that is substantially delayed from the original response. Since the consequences of one's actions often do not become known until after a delay, it is important to understand whether delayed feedback can produce neural responses similar to those elicited by immediate-feedback presentation. We investigated this issue by using functional magnetic resonance imaging (fMRI) as participants performed a paired-associate learning task with 180 distinct trials. Feedback indicating response accuracy was presented immediately, after a delay of 25 min, or not at all. Both immediate and delayed feedback led to significant gains in accuracy on a posttest, relative to no feedback. Replicating previous work, we found that the caudate nuclei showed greater activation for positive feedback than for negative feedback when the feedback was presented immediately. In addition, delayed feedback also led to differential caudate activity to positive versus negative feedback. Delayed negative feedback also produced significant activation of the putamen and globus pallidus (the lentiform nucleus), relative to no feedback and delayed positive feedback. This suggests that the caudate nucleus is sensitive to the affective nature of feedback, across different time scales, while the lentiform nucleus may be particularly involved in processing the information carried by negative feedback after a substantial delay.


Assuntos
Aprendizagem por Associação/fisiologia , Gânglios da Base/irrigação sanguínea , Gânglios da Base/fisiologia , Retroalimentação Fisiológica/fisiologia , Adulto , Análise de Variância , Animais , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Oxigênio/sangue , Fatores de Tempo , Aprendizagem Verbal , Vocabulário , Adulto Jovem
12.
Mult Scler Relat Disord ; 75: 104754, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37220713

RESUMO

BACKGROUND: Performance feedback is vital to rehabilitation interventions that treat cognitive impairments from multiple sclerosis (MS). Optimal treatment relies on participants' motivation to learn from feedback throughout these interventions. Cognitive fatigue, a prevalent symptom of MS, is associated with aberrant reward processing, which necessitates research into how fatigue affects perceived reward value of feedback in these individuals. The current study investigated how trait fatigue influences subjective valuation of feedback and subsequent feedback-seeking behavior in people with MS. METHODS: 33 MS and 32 neurotypical (NT) participants completed a willingness-to-pay associative memory paradigm that assessed feedback valuation via trial-by-trial decisions to either purchase or forego feedback in service of maximizing a performance-contingent monetary reward. Participant ratings of trait fatigue were also collected. Generalized logistic mixed modeling was used to analyze factors that influenced trial-wise feedback purchase decisions and task performance. RESULTS: Despite reporting greater trait fatigue, MS participants purchased comparable amounts of feedback as NT participants. Like NT participants, MS participants were more likely to purchase feedback when they were less confident about response accuracy. MS participants also performed comparably to NT participants, who both particularly benefited from purchase decisions that yielded negative feedback (i.e., indicating a response error). CONCLUSIONS: Trait cognitive fatigue may not impact performance feedback valuation in people with MS. Nonetheless, confidence in performance may drive their feedback-seeking behavior and may serve as a target for improving learning throughout cognitive rehabilitation and maximizing treatment success.


Assuntos
Disfunção Cognitiva , Esclerose Múltipla , Humanos , Esclerose Múltipla/complicações , Esclerose Múltipla/psicologia , Retroalimentação , Motivação , Disfunção Cognitiva/complicações , Fadiga/complicações , Cognição/fisiologia
13.
Neuroimage Clin ; 37: 103287, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36516729

RESUMO

Effective learning from performance feedback is vital for adaptive behavior regulation necessary for successful cognitive performance. Yet, how this learning operates in clinical groups that experience cognitive dysfunction is not well understood. Multiple sclerosis (MS) is an autoimmune, degenerative disease of the central nervous system characterized by physical and cognitive dysfunction. A highly prevalent impairment in MS is cognitive fatigue (CF). CF is associated with altered functioning within cortico-striatal regions that also facilitate feedback-based learning in neurotypical (NT) individuals. Despite this cortico-striatal overlap, research about feedback-based learning in MS, its associated neural underpinnings, and its sensitivity to CF, are all lacking. The present study investigated feedback-based learning ability in MS, as well as associated cortico-striatal function and connectivity. MS and NT participants completed a functional magnetic resonance imaging (fMRI) paired-word association task during which they received trial-by-trial monetary, non-monetary, and uninformative performance feedback. Despite reporting greater CF throughout the task, MS participants displayed comparable task performance to NTs, suggesting preserved feedback-based learning ability in the MS group. Both groups recruited the ventral striatum (VS), caudate nucleus, and ventromedial prefrontal cortex in response to the receipt of performance feedback, suggesting that people with MS also recruit cortico-striatal regions during feedback-based learning. However, compared to NT participants, MS participants also displayed stronger functional connectivity between the VS and task-relevant regions, including the left angular gyrus and right superior temporal gyrus, in response to feedback receipt. Results indicate that CF may not interfere with feedback-based learning in MS. Nonetheless, people with MS may recruit alternative connections with the striatum to assist with this form of learning. These findings have implications for cognitive rehabilitation treatments that incorporate performance feedback to remediate cognitive dysfunction in clinical populations.


Assuntos
Esclerose Múltipla , Estriado Ventral , Humanos , Núcleo Caudado , Retroalimentação , Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla/complicações , Esclerose Múltipla/diagnóstico por imagem , Córtex Pré-Frontal , Recompensa
14.
J Neurosci ; 31(7): 2474-80, 2011 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-21325514

RESUMO

Contingency theories of goal-directed action propose that experienced disjunctions between an action and its specific consequences, as well as conjunctions between these events, contribute to encoding the action-outcome association. Although considerable behavioral research in rats and humans has provided evidence for this proposal, relatively little is known about the neural processes that contribute to the two components of the contingency calculation. Specifically, while recent findings suggest that the influence of action-outcome conjunctions on goal-directed learning is mediated by a circuit involving ventromedial prefrontal, medial orbitofrontal cortex, and dorsomedial striatum, the neural processes that mediate the influence of experienced disjunctions between these events are unknown. Here we show differential responses to probabilities of conjunctive and disjunctive reward deliveries in the ventromedial prefrontal cortex, the dorsomedial striatum, and the inferior frontal gyrus. Importantly, activity in the inferior parietal lobule and the left middle frontal gyrus varied with a formal integration of the two reward probabilities, ΔP, as did response rates and explicit judgments of the causal efficacy of the action.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiologia , Condicionamento Operante/fisiologia , Objetivos , Recompensa , Encéfalo/anatomia & histologia , Encéfalo/irrigação sanguínea , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Vias Neurais/irrigação sanguínea , Vias Neurais/fisiologia , Oxigênio/sangue , Probabilidade , Estatística como Assunto
15.
Cogn Affect Behav Neurosci ; 12(2): 361-72, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22194237

RESUMO

Negative feedback can signal poor performance, but it also provides information that can help learners reach the goal of task mastery. The primary aim of this study was to test the hypothesis that the amount of information provided by negative feedback during a paired-associate learning task influences feedback-related processing in the caudate nucleus. To do this, we manipulated the number of response options: With two options, positive and negative feedback provide equal amounts of information, whereas with four options, positive feedback provides more information than does negative feedback. We found that positive and negative feedback activated the caudate similarly when there were two response options. With four options, the caudate's response to negative feedback was reduced. A secondary goal was to investigate the link between brain-based measures of feedback-related processing and behavioral indices of learning. Analysis of the posttest measures showed that trials with positive feedback were associated with higher posttest confidence ratings. Additionally, when positive feedback was delivered, caudate activity was greater for trials with high than with low posttest confidence. This experiment demonstrated the context sensitivity of feedback processing and provided evidence that feedback processing in the striatum can contribute to the strengthening of the representations available within declarative memory.


Assuntos
Corpo Estriado/fisiologia , Retroalimentação Psicológica/fisiologia , Memória Episódica , Recompensa , Análise de Variância , Aprendizagem por Associação/fisiologia , Mapeamento Encefálico , Comportamento de Escolha/fisiologia , Corpo Estriado/irrigação sanguínea , Feminino , Lateralidade Funcional , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Oxigênio/sangue , Córtex Pré-Frontal/irrigação sanguínea , Córtex Pré-Frontal/fisiologia , Tempo de Reação , Vocabulário , Adulto Jovem
16.
PLoS One ; 15(6): e0234424, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32530930

RESUMO

Researchers have exerted tremendous efforts to empirically study how habits form and dominate at the expense of deliberation, yet we know very little about breaking these rigid habits to restore goal-directed control. In a three-experiment study, we first illustrate a novel approach of studying well-learned habits, in order to effectively demonstrate habit disruption. In Experiment 1, we use a Go/NoGo task with familiar color-response associations to demonstrate outcome-insensitivity when compared to novel, more flexible associations. Specifically, subjects perform more accurately when the required mapping is the familiar association of green-Go/red-NoGo than when it is red-Go/green-NoGo, confirming outcome-insensitive, habitual control. As a control condition, subjects show equivalent performance with unfamiliar color-response mappings (using the colors blue and purple mapped to Go and NoGo responses). Next, in Experiments 2 and 3, we test a motivation-based feedback manipulation in varying magnitudes (i.e., performance feedback with and without monetary incentives) to break the well-established habits elicited by our familiar stimuli. We find that although performance feedback prior to the contingency reversal test is insufficient to disrupt outcome-insensitivity in Experiment 2, a combination of performance feedback and monetary incentive is able to restore goal-directed control in Experiment 3, effectively breaking the habits. As the first successful demonstration of well-learned habit disruption in the laboratory, these findings provide new insights into how we execute and modify habits, while fostering new and translational research avenues that may be applicable to treating habit-based pathologies.


Assuntos
Hábitos , Adolescente , Aprendizagem por Associação , Cor , Feminino , Objetivos , Humanos , Aprendizagem , Masculino , Motivação , Estimulação Luminosa , Análise e Desempenho de Tarefas , Adulto Jovem
17.
Cortex ; 127: 191-207, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32222572

RESUMO

Attention-deficit/hyperactivity disorder (ADHD) poses debilitating impairments in the neurobehavioral systems governing reward-related processes-key to the control of motivated behaviors. Individuals with ADHD may rely on a motivational control system that favors cue-driven habits-rooted in the posterior putamen-over caudate and prefrontal cortex-driven goal-directed behaviors. We examined the neurobehavioral correlates of motivational control in ADHD. Twenty-five adults with ADHD and 25 neurotypicals underwent fMRI while training on two stimulus-response-outcome associations. A devaluation procedure followed, whereby they were selectively satiated on one of the snack outcomes, decreasing its value. A subsequent extinction test determined outcome-sensitivity (i.e., whether responses towards devalued snack diminished). Despite behavioral similarities, the ADHD group displayed a distinct neural signature marked by enhanced posterior putamen activation as a function of training. This region also displayed diminished functional connectivity with the dorsal anterior cingulate cortex, which is associated with top-down control. Our whole-brain analysis yielded ADHD-specific posterior putamen and opercular/insular cortex activity over the course of training-regions associated with stimulus-sensitivity and maladaptively rigid behaviors, respectively. Neural comparisons also identified hyper-recruitment of the hippocampus in the ADHD group. These results highlight corticostriatal discrepancies in ADHD, possibly serving as a biomarker of the disorder.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Adulto , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Humanos , Imageamento por Ressonância Magnética , Motivação
18.
Eur J Neurosci ; 29(11): 2225-32, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19490086

RESUMO

Habits are characterized by an insensitivity to their consequences and, as such, can be distinguished from goal-directed actions. The neural basis of the development of demonstrably outcome-insensitive habitual actions in humans has not been previously characterized. In this experiment, we show that extensive training on a free-operant task reduces the sensitivity of participants' behavior to a reduction in outcome value. Analysis of functional magnetic resonance imaging data acquired during training revealed a significant increase in task-related cue sensitivity in a right posterior putamen-globus pallidus region as training progressed. These results provide evidence for a shift from goal-directed to habit-based control of instrumental actions in humans, and suggest that cue-driven activation in a specific region of dorsolateral posterior putamen may contribute to the habitual control of behavior in humans.


Assuntos
Corpo Estriado/fisiologia , Hábitos , Aprendizagem/fisiologia , Adulto , Condicionamento Operante/fisiologia , Comportamento Alimentar/fisiologia , Feminino , Humanos , Masculino , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Adulto Jovem
19.
Biol Psychol ; 146: 107715, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31212006

RESUMO

Intelligence mindset, which denotes individual beliefs about whether intelligence is fixed versus malleable, shapes academic success, but the neural mechanisms underlying mindset-related differences in learning are unknown. Here, we probe the effects of individual differences in mindset on neural responses to negative feedback after a competence threat manipulation. We hypothesized that when their competence was threatened, participants with fixed mindsets would interpret further negative feedback as punishing. After receiving either no score or a competence-threatening IQ score, participants performed a learning task with feedback that emphasized either the evaluative or informational weight of negative feedback. Participants who experienced the competence threat had the strongest predictive relationships between mindset, performance, and caudate activation. The competence threat may have compounded the subjective punishment of negative feedback for fixed mindsets relative to growth mindsets, causing poorer learning from negative feedback in the evaluative context and inflexible striatal responses to negative feedback across feedback contexts.


Assuntos
Inteligência , Aprendizagem , Memória , Competência Mental/psicologia , Retroalimentação Psicológica , Feminino , Humanos , Individualidade , Masculino
20.
Front Psychol ; 10: 1997, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31551864

RESUMO

Attention-deficit/hyperactivity disorder (ADHD) is associated with neurobehavioral reward system dysfunctions that pose debilitating impairments in adaptive decision-making. A candidate mechanism for such anomalies in ADHD may be a compromise in the control of motivated behaviors. Thus, demonstrating and restoring potential motivational control irregularities may serve significant clinical benefit. The motivational control of action guides goal-directed behaviors that are driven by outcome value, and habits that are inflexibly cue-triggered. We examined whether ADHD symptomology within the general population is linked to habitual control, and whether a motivation-based manipulation can break well-learned habits. We obtained symptom severity scores from 106 participants and administered a Go/NoGo task that capitalizes on familiar, well-learned associations (green-Go and red-NoGo) to demonstrate outcome-insensitivity when compared to newly learned Go/NoGo associations. We tested for outcome-insensitive habits by changing the Go and NoGo contingencies, such that Go signals became NoGo signals and vice versa. We found that generally, participants responded less accurately when green and red stimuli were mapped to color-response contingencies that were incongruent with daily experiences, whereas novel Go/NoGo stimuli evoked similar accuracy regardless of color-response mappings. Thus, our Go/NoGo task successfully elicited outcome-insensitive habits (i.e., persistent responses to familiar stimuli without regard for consequences); however, this effect was independent of ADHD symptomology. Nevertheless, we found an association between hyperactivity and congruent Go response latency, suggesting heightened pre-potency to perform habitual Go actions as hyperactivity increases. To examine habit disruption, participants returned to the lab and underwent the familiar version of the Go/NoGo task, but were given mid-experiment performance tracking information and a monetary incentive prior to contingency change. We found that this motivational boost via dual feedback prevented the incongruency-related accuracy impairment, effectively breaking the habit, albeit independent of ADHD symptomology. Our findings present only a modest link between ADHD symptomology and motivational control, which may be due to compensatory mechanisms in ADHD driving goal-directed control, or our task's potential insensitivity to individual differences in ADHD symptomology. Further investigations may be crucial for determining whether ADHD is related to motivational impairments.

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