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1.
J Cogn Neurosci ; : 1-19, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38940737

RESUMO

Need states are internal states that arise from deprivation of crucial biological stimuli. They direct motivation, independently of external learning. Despite their separate origin, they interact with reward processing systems that respond to external stimuli. This article aims to illuminate the functioning of the needing system through the lens of active inference, a framework for understanding brain and cognition. We propose that need states exert a pervasive influence on the organism, which in active inference terms translates to a "pervasive surprise"-a measure of the distance from the organism's preferred state. Crucially, we define needing as an active inference process that seeks to reduce this pervasive surprise. Through a series of simulations, we demonstrate that our proposal successfully captures key aspects of the phenomenology and neurobiology of needing. We show that as need states increase, the tendency to occupy preferred states strengthens, independently of external reward prediction. Furthermore, need states increase the precision of states (stimuli and actions) leading to preferred states, suggesting their ability to amplify the value of reward cues and rewards themselves. Collectively, our model and simulations provide valuable insights into the directional and underlying influence of need states, revealing how this influence amplifies the wanting or liking associated with relevant stimuli.

2.
Evol Psychol ; 21(3): 14747049231203394, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37770021

RESUMO

Previous research indicates that the anticipatory shame an individual feels at the prospect of taking a disgraceful action closely tracks the degree to which local audiences, and even foreign audiences, devalue those individuals who take that action. This supports the proposition that the shame system (a) defends the individual against the threat of being devalued, and (b) balances the competing demands of operating effectively yet efficiently. The stimuli events used in previous research were highly variable in their perceived disgracefulness, ranging in rated shame and audience devaluation from low (e.g., missing the target in a throwing game) to high (e.g., being discovered cheating on one's spouse). But how precise is the tracking of audience devaluation by the shame system? Would shame track devaluation for events that are similarly low (or high) in disgracefulness? To answer this question, we conducted a study with participants from the United States and India. Participants were assigned, between-subjects, to one of two conditions: shame or audience devaluation. Within-subjects, participants rated three low-variation sets of 25 scenarios each, adapted from Mu, Kitayama, Han, & Gelfand (2015), which convey (a) appropriateness (e.g., yelling at a rock concert), (b) mild disgracefulness (e.g., yelling on the metro), and (c) disgracefulness (e.g., yelling in the library), all presented un-blocked, in random order. Consistent with previous research, shame tracked audience devaluation across the high-variation superset of 75 scenarios, both within and between cultures. Critically, shame tracked devaluation also within each of the three sets. The shame system operates with high precision.


Assuntos
Emoções , Vergonha , Humanos , Estados Unidos , Processos Mentais
3.
Scand J Psychol ; 64(5): 679-692, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37096738

RESUMO

Miller et al. (2010) previously suggested that borderline pathology, vulnerable narcissism, and Factor 2 psychopathy share a common "Vulnerable Dark Triad" (VDT) core. The present study (N = 1,023 community participants) aims to test that hypothesis using exploratory and confirmatory bifactor analyses. We found support for a bifactor model that obtained satisfactory fits and other adequate validity indices, which included a general VDT factor and three group factors (Reckless, Entitled, Hiding). The general VDT factor was mostly saturated with borderline symptoms items reflecting self-hatred and worthlessness, which did not form a group factor; these results add to previous research suggesting that features of borderline pathology may represent the core of personality pathology. The three group factors had distinctive relationships with Dark Triad traits, pathological trait domains, and aggression. In contrast with the three group factors, the general VDT factor more strongly incremented the prediction of negative affectivity and hostility; the group factors more strongly incremented the prediction of grandiosity, egocentrism, callousness, Machiavellianism, and direct (physical/verbal) aggression. Alignment of the retained bifactor model with influent models of personality pathology and conceptual/methodological implications of the present results for research on the hypothesized VDT are discussed, as well as some clinical implications of the findings.


Assuntos
Maquiavelismo , Personalidade , Humanos , Transtorno da Personalidade Antissocial , Narcisismo , Agressão
4.
PLoS One ; 17(11): e0277508, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36383514

RESUMO

Adequate social functioning during childhood requires context-appropriate social decision-making. To make such decisions, children rely on their social norms, conceptualized as cognitive models of shared expectations. Since social norms are dynamic, children must adapt their models of shared expectations and modify their behavior in line with their social environment. This study aimed to investigate children's abilities to use social information to adapt their fairness norm and to identify the computational mechanism governing this process. Thirty children (7-11 years, M = 7.9 SD = 0.85, 11 girls) played the role of Responder in a modified version of the Ultimatum Game-a two-player game based on the fairness norm-in which they had to choose to accept or reject offers from different Proposers. Norm adaptation was assessed by comparing rejection rates before and after a conditioning block in which children received several low offers. Computational models were compared to test which best explains children's behavior during the game. Mean rejection rate decreased significantly after receiving several low offers suggesting that children have the ability to dynamically update their fairness norm and adapt to changing social environments. Model-based analyses suggest that this process involves the computation of norm-prediction errors. This is the first study on norm adaptation capacities in school-aged children that uses a computational approach. Children use implicit social information to adapt their fairness norm to changing environments and this process appears to be supported by a computational mechanism in which norm-prediction errors are used to update norms.


Assuntos
Tomada de Decisões , Comportamento Social , Criança , Feminino , Humanos , Normas Sociais , Simulação por Computador , Jogos Experimentais
5.
Brain Sci ; 12(9)2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-36138963

RESUMO

Sociomoral reasoning (SMR) is an essential component of social functioning allowing children to establish judgments based on moral criteria. The progressive emergence and complexification of SMR during childhood is thought to be underpinned by a range of characteristics and abilities present in the preschool years. Past studies have mostly examined concurrent associations between individual factors and SMR. Using a more comprehensive and predictive approach to identify early predictors of school-age SMR would contribute to a more complete picture of SMR development. This study aimed to investigate the contribution of four domains of preschool predictors to SMR at school-age: demographic (age, sex, parental education), cognitive (executive and sociocognitive functions), behavioral (internalizing and externalizing behaviors), and familial (parent-child interactions, parental stress) factors. Parents of 122 children 3 to 5 years (M = 3.70, SD = 0.66 years, 51% girls) completed questionnaires and children were administered executive and sociocognitive tasks. Parent-child interactions were assessed using an observational approach. SMR was measured four years later using the SoMoral task. A four-step hierarchical regression analysis revealed that executive functions and internalizing problems were significant independent predictors of SMR. These findings provide a more comprehensive understanding of the early precursors of SMR during childhood.

6.
Brain Behav ; 12(9): e32713, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36000558

RESUMO

Consumption and its excesses are sometimes explained by imbalance of need or lack of control over "wanting." "Wanting" assigns value to cues that predict rewards, whereas "needing" assigns value to biologically significant stimuli that one is deprived of. Here we aimed at studying how the brain activation patterns related to value of "wanted" stimuli differs from that of "needed" stimuli using activation likelihood estimation neuroimaging meta-analysis approaches. We used the perception of a cue predicting a reward for "wanting" related value and the perception of food stimuli in a hungry state as a model for "needing" related value. We carried out separate, contrasts, and conjunction meta-analyses to identify differences and similarities between "wanting" and "needing" values. Our overall results for "wanting" related value show consistent activation of the ventral tegmental area, striatum, and pallidum, regions that both activate behavior and direct choice, while for "needing" related value, we found an overall consistent activation of the middle insula and to some extent the caudal-ventral putamen, regions that only direct choice. Our study suggests that wanting has more control on consumption and behavioral activation.


Assuntos
Imageamento por Ressonância Magnética , Recompensa , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Mapeamento Encefálico , Sinais (Psicologia) , Fome/fisiologia , Motivação
7.
Brain Res ; 1784: 147850, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35231420

RESUMO

Individuals are faster at detecting threatening stimuli than neutral stimuli. While generally considered a rapid bottom-up response, this threat superiority effect is also modulated by top-down mechanisms known to rely on the dorsolateral prefrontal cortex (DLPFC). What remains unclear is whether the response is modulated only at later stages of processing, or whether rapid attention to threat itself is controlled in a top-down manner. To test this, we used repetitive transcranial magnetic stimulation (rTMS) to inhibit activity in the DLPFC, and measured EEG to index the immediate neural response to threat. Twenty participants attended two sessions where they performed a visual search task with threatening or neutral targets. Prior to this, they received 15 min of 1 Hz inhibitory or sham rTMS targeting the right DLPFC. We measured the impact of rTMS on the P1, a rapid visually-evoked potential that is modulated by attention. We found that threatening targets increased the amplitude of the P1 in the sham condition, but inhibition of the DLPFC abolished this increase. These results suggest that the neural signature of rapid attentional detection of threat, even at its earliest stage, is influenced in a top-down fashion by the right DLPFC.


Assuntos
Córtex Pré-Frontal , Estimulação Magnética Transcraniana , Córtex Pré-Frontal Dorsolateral , Humanos , Inibição Psicológica , Córtex Pré-Frontal/fisiologia , Estimulação Magnética Transcraniana/métodos
8.
Psychol Assess ; 34(3): e15-e25, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34990191

RESUMO

Vachon and Lynam (2016) recently introduced a new measure of empathy, the Affective and Cognitive Measure of Empathy (ACME). Besides assessing the traditional dimensions of cognitive and affective empathy, the ACME includes an affective dissonance scale that covers "antiempathy," an important feature of the construct with prominent predictive value not included in other empathy measures. The aim of this study is to provide data on the French version of the ACME. A sample of 851 community-dwelling participants (59.4% female) completed online the ACME questionnaire along with other measures of empathy, dark and pathological personality traits, and aggression. The original ACME bifactor exploratory structural equation modeling structure (i.e., the three empathy dimensions of Cognitive, Affective Resonance, and Affective Dissonance with positive and negative wording items as method bifactors) was successfully reproduced with the French version. Furthermore, these scales displayed satisfying internal consistency coefficients, as well as good item properties according to Classical Test Theory. Convergent validity indices were also similar to those reported for the original English version, and scale scores reached full invariance across gender and proved to be partially invariant across language when comparing the present data to those from the original validation study. The French version of the ACME is well aligned with the original English version and offers a valuable alternative to French researchers and clinicians interested in measuring the various dimensions of empathy. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Assuntos
Empatia , Idioma , Cognição , Feminino , Humanos , Masculino , Transtornos da Personalidade/psicologia , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários
9.
Sante Ment Que ; 47(2): 95-111, 2022.
Artigo em Francês | MEDLINE | ID: mdl-37279317

RESUMO

Objectives Shame is a painful feeling that one feels when under the impression of having committed an offence or contravened to a personal or moral standard. Shame experiences are often intense and entail a global, negative self-evaluation; persons then feel like they are bad, weak, worthless, or deserving others' contempt. Some people are more prone to shame feelings. Although shame is not listed as a diagnostic criterion of borderline personality disorder (BPD) in the DSM-5, studies suggest that shame is an important feature in individuals with BPD. The aim of this study is to garner additional data to document shame proneness in individuals presenting with borderline symptomatology in the population from the Province of Quebec. Method Overall, 646 community adults from the Province of Quebec completed online the brief version of the Borderline Symptom List (BSL-23), measuring the severity of symptoms associated with BPD from a dimensional perspective, and to the Experience of Shame Scale (ESS), measuring shame proneness in various areas of a person's life. Participants were then compared on their shame scores after they were assigned to one of the four groups based on Kleindienst et al. (2020) classification of severity of borderline symptoms: (a) none or low symptoms (n = 173), (b) mild symptoms (n = 316), (c) moderate symptoms (n = 103), or (d) high, very high or extremely high symptoms (n = 54). Results Between-group differences were found with large effect sizes in all shame areas measured by the ESS, suggesting that shame feelings tend to be greater in persons presenting more borderline traits. Conclusion Results are discussed in a clinical perspective of BPD, emphasizing the importance of having shame as a clinical target in psychotherapy with these clients. Furthermore, our results raise conceptual questions regarding how to integrate shame in the assessment and treatment of BPD.


Assuntos
Transtorno da Personalidade Borderline , Adulto , Humanos , Transtorno da Personalidade Borderline/diagnóstico , Transtorno da Personalidade Borderline/epidemiologia , Transtorno da Personalidade Borderline/terapia , Quebeque , Vergonha , Emoções , Psicoterapia
10.
Neurosci Biobehav Rev ; 126: 289-303, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33781834

RESUMO

Recent overarching frameworks propose that various human social interactions are commonly supported by a set of fundamental neuropsychological processes, including social cognition, motivation, and cognitive control. However, it remains unclear whether brain networks implicated in these functional constructs are consistently engaged in diverse social interactions. Based on ample evidence from human brain imaging studies (342 contrasts, 7234 participants, 3328 foci), we quantitatively synthesized brain areas involved in broad domains of social interactions, including social interactions versus non-social contexts, positive/negative aspects of social interactions, social learning, and social norms. We then conducted brain network analysis on the ensuing brain regions and characterized the psychological function profiles of identified brain networks. Our findings revealed that brain regions consistently involved in diverse social interactions mapped onto default mode network, salience network, subcortical network and central executive network, which were respectively implicated in social cognition, motivation and cognitive control. These findings implicate a heuristic integrative framework to understand human social life from the perspective of component process and network integration.


Assuntos
Mapeamento Encefálico , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Cognição , Humanos , Rede Nervosa , Neuroimagem
11.
PLoS One ; 15(12): e0242996, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33259533

RESUMO

Human behavior is framed by several social structures. In the present study, we focus on two of the most important determinants of social structures: social norms and political orientation. Social norms are implicit models of shared expectations about how people should behave in different social contexts. Although humans are very sensitive to violations in social norms, there are important individual differences in our sensitivity to these violations. The second concept this study focuses on is political orientation that is define by a continuum from left (liberal) to right (conservative). Individual political orientation has been found to be related to various individual traits, such as cognitive style or sensitivity to negative stimuli. Here, we propose to study the relation between sensitivity to social norm violation and political orientation. Participants completed a task presenting scenarios with different degrees of social norm violation and a questionnaire to measure their political opinions on economic and identity issues. Using hierarchical regressions, we show that individual differences in sensitivity to social norm violation are partly explained by political orientation, and more precisely by the identity axis. The more individuals have right-oriented political opinions, the more they are sensitive to social norm violation, even when multiple demographics variables are considered. Our results suggest that political orientation, especially according to identity issues, is a significant factor of individual differences in social norm processing.


Assuntos
Atitude , Política , Normas Sociais , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
12.
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
13.
Neuroimage ; 189: 45-54, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30630079

RESUMO

Training and repeated exposure to odorants leads to enhanced olfactory sensitivity. So far, the efficacy of intensive olfactory training on olfactory function in a healthy population and its underlying neurobiological basis remain poorly known. This study investigated the effects of a 6-week intensive and well-controlled olfactory training on olfactory function and brain structure/neuroplasticity. Thirty-six healthy young individuals were recruited and randomly distributed in three groups: (1) 12 participants underwent daily intensive olfactory training of at least 20 min that included an (a) odor intensity classification task, an (b) odor quality classification task and an (c) target odor detection task, (2) 12 participants underwent an equivalent visual control training, and (3) 12 control individuals did not participate in any training. Before and after the training period, all participants performed a series of olfactory tests and those from groups 1 and 2 underwent structural magnetic resonance (MR) imaging, from which we obtained measures such as cortical thickness and tissue density. Participants improved in the respectively trained tasks throughout the 6-weeks training period. Those who underwent olfactory training improved general olfactory function compared to control participants, especially in odor identification, thus showing intramodal transfer. Further, MR imaging analysis revealed that olfactory training led to increased cortical thickness in the right inferior frontal gyrus, the bilateral fusiform gyrus and the right entorhinal cortex. This research shows that intensive olfactory training can generally improve olfactory function and that this improvement is associated with changes in the structure of olfactory processing areas of the brain.


Assuntos
Córtex Entorrinal/anatomia & histologia , Neuroimagem/métodos , Plasticidade Neuronal/fisiologia , Percepção Olfatória/fisiologia , Prática Psicológica , Córtex Pré-Frontal/anatomia & histologia , Lobo Temporal/anatomia & histologia , Adolescente , Adulto , Córtex Entorrinal/diagnóstico por imagem , Córtex Entorrinal/fisiologia , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Distribuição Aleatória , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/fisiologia , Adulto Jovem
14.
Nat Commun ; 9(1): 4705, 2018 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-30459305

RESUMO

Early childhood educational investment produces positive effects on cognitive and non-cognitive skills, health, and socio-economic success. However, the effects of such interventions on social decision-making later in life are unknown. We recalled participants from one of the oldest randomized controlled studies of early childhood investment-the Abecedarian Project (ABC)-to participate in well-validated interactive economic games that probe social norm enforcement and planning. We show that in a repeated-play ultimatum game, ABC participants who received high-quality early interventions strongly reject unequal division of money across players (disadvantageous or advantageous) even at significant cost to themselves. Using a multi-round trust game and computational modeling of social exchange, we show that the same intervention participants also plan further into the future. These findings suggest that high quality early childhood investment can result in long-term changes in social decision-making and promote social norm enforcement in order to reap future benefits.


Assuntos
Tomada de Decisões/fisiologia , Investimentos em Saúde , Rememoração Mental/fisiologia , Normas Sociais , Criança , Pré-Escolar , Cognição , Intervenção Educacional Precoce , Feminino , Jogos Experimentais , Humanos , Masculino , Modelos Psicológicos , Comportamento Social , Fatores Socioeconômicos
15.
Hum Brain Mapp ; 39(1): 440-458, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29064617

RESUMO

Social comparison is ubiquitous across human societies with dramatic influence on people's well-being and decision making. Downward comparison (comparing to worse-off others) and upward comparison (comparing to better-off others) constitute two types of social comparisons that produce different neuropsychological consequences. Based on studies exploring neural signatures associated with downward and upward comparisons, the current study utilized a coordinate-based meta-analysis to provide a refinement of understanding about the underlying neural architecture of social comparison. We identified consistent involvement of the ventral striatum and ventromedial prefrontal cortex in downward comparison and consistent involvement of the anterior insula and dorsal anterior cingulate cortex in upward comparison. These findings fit well with the "common-currency" hypothesis that neural representations of social gain or loss resemble those for non-social reward or loss processing. Accordingly, we discussed our findings in the framework of general reinforcement learning (RL) hypothesis, arguing how social gain/loss induced by social comparisons could be encoded by the brain as a domain-general signal (i.e., prediction errors) serving to adjust people's decisions in social settings. Although the RL account may serve as a heuristic framework for the future research, other plausible accounts on the neuropsychological mechanism of social comparison were also acknowledged. Hum Brain Mapp 39:440-458, 2018. © 2017 Wiley Periodicals, Inc.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Percepção Social , Neuroimagem Funcional , Humanos
16.
Soc Cogn Affect Neurosci ; 12(12): 1972-1982, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-28981876

RESUMO

As models of shared expectations, social norms play an essential role in our societies. Since our social environment is changing constantly, our internal models of it also need to change. In humans, there is mounting evidence that neural structures such as the insula and the ventral striatum are involved in detecting norm violation and updating internal models. However, because of methodological challenges, little is known about the possible involvement of midbrain structures in detecting norm violation and updating internal models of our norms. Here, we used high-resolution cardiac-gated functional magnetic resonance imaging and a norm adaptation paradigm in healthy adults to investigate the role of the substantia nigra/ventral tegmental area (SN/VTA) complex in tracking signals related to norm violation that can be used to update internal norms. We show that the SN/VTA codes for the norm's variance prediction error (PE) and norm PE with spatially distinct regions coding for negative and positive norm PE. These results point to a common role played by the SN/VTA complex in supporting both simple reward-based and social decision making.


Assuntos
Jogos Experimentais , Percepção Social , Substância Negra/fisiologia , Área Tegmentar Ventral/fisiologia , Adaptação Psicológica , Adulto , Tomada de Decisões , Emoções , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Modelos Psicológicos , Recompensa , Meio Social , Adulto Jovem
17.
Sci Rep ; 6: 34907, 2016 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-27703276

RESUMO

Motor representations in the human mirror neuron system are tuned to respond to specific observed actions. This ability is widely believed to be influenced by genetic factors, but no study has reported a genetic variant affecting this system so far. One possibility is that genetic variants might interact with visuomotor associative learning to configure the system to respond to novel observed actions. In this perspective, we conducted a candidate gene study on the Brain-derived neurotrophic factor (BDNF) Val66Met polymorphism, a genetic variant linked to motor learning in regions of the mirror neuron system, and tested the effect of this polymorphism on motor facilitation and visuomotor associative learning. In a single-pulse TMS study carried on 16 Met (Val/Met and Met/Met) and 16 Val/Val participants selected from a large pool of healthy volunteers, Met participants showed significantly less muscle-specific corticospinal sensitivity during action observation, as well as reduced visuomotor associative learning, compared to Val homozygotes. These results are the first evidence of a genetic variant tuning sensitivity to action observation and bring to light the importance of considering the intricate relation between genetics and associative learning in order to further understand the origin and function of the human mirror neuron system.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/genética , Neurônios-Espelho/fisiologia , Adulto , Alelos , Potenciais Evocados , Feminino , Variação Genética , Genótipo , Homozigoto , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Adulto Jovem
18.
Front Hum Neurosci ; 10: 458, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27683548

RESUMO

Transcranial magnetic stimulation (TMS) studies have shown that observing an action induces muscle-specific changes in corticospinal excitability. From a signal detection theory standpoint, this pattern can be related to sensitivity, which here would measure the capacity to distinguish between two action observation conditions. In parallel to these TMS studies, action observation has also been linked to behavioral effects such as motor priming and interference. It has been hypothesized that behavioral markers of action observation could be related to TMS markers and thus represent a potentially cost-effective mean of assessing the functioning of the action-perception system. However, very few studies have looked at possible relationships between these two measures. The aim of this study was to investigate if individual differences in sensitivity to action observation could be related to the behavioral motor priming and interference effects produced by action observation. To this end, 14 healthy participants observed index and little finger movements during a TMS task and a stimulus-response compatibility task. Index muscle displayed sensitivity to action observation, and action observation resulted in significant motor priming+interference, while no significant effect was observed for the little finger in both task. Nevertheless, our results indicate that the sensitivity measured in TMS was not related to the behavioral changes measured in the stimulus-response compatibility task. Contrary to a widespread assumption, the current results indicate that individual differences in physiological and behavioral markers of action observation may be unrelated. This could have important impacts on the potential use of behavioral markers in place of more costly physiological markers of action observation in clinical settings.

19.
Hum Brain Mapp ; 37(7): 2602-15, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27038008

RESUMO

The habenula is a hub for cognitive and emotional signals that are relayed to the aminergic centers in the midbrain and, thus, plays an important role in goal-oriented behaviors. Although it is well described in rodents and non-human primates, the habenula functional network remains relatively uncharacterized in humans, partly because of the methodological challenges associated with the functional magnetic resonance imaging of small structures in the brain. Using high-resolution cardiac-gated resting state imaging in healthy humans and precisely identifying each participants' habenula, we show that the habenula is functionally coupled with the insula, parahippocampus, thalamus, periaqueductal grey, pons, striatum and substantia nigra/ventral tegmental area complex. Furthermore, by separately examining and comparing the functional maps from the left and right habenula, we provide the first evidence of an asymmetry in the functional connectivity of the habenula in humans. Hum Brain Mapp 37:2602-2615, 2016. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.


Assuntos
Técnicas de Imagem de Sincronização Cardíaca , Lateralidade Funcional , Habenula/fisiologia , Imageamento por Ressonância Magnética , Adulto , Mapeamento Encefálico/métodos , Técnicas de Imagem de Sincronização Cardíaca/métodos , Feminino , Habenula/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiologia , Tamanho do Órgão , Descanso
20.
PLoS One ; 11(2): e0149911, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26901829

RESUMO

Empathy is an important driver of human social behaviors and presents genetic roots that have been studied in neuroimaging using the intermediate phenotype approach. Notably, the Val66Met polymorphism of the Brain-derived neurotrophic factor (BDNF) gene has been identified as a potential target in neuroimaging studies based on its influence on emotion perception and social cognition, but its impact on self-reported empathy has never been documented. Using a neurogenetic approach, we investigated the association between the BDNF Val66Met polymorphism and self-reported empathy (Davis' Interpersonal Reactivity Index; IRI) in a sample of 110 young adults. Our results indicate that the BDNF genotype is significantly associated with the linear combination of the four facets of the IRI, one of the most widely used self-reported empathy questionnaire. Crucially, the effect of BDNF Val66Met goes beyond the variance explained by two polymorphisms of the oxytocin transporter gene previously associated with empathy and its neural underpinnings (OXTR rs53576 and rs2254298). These results represent the first evidence suggesting a link between the BDNF gene and self-reported empathy and warrant further studies of this polymorphism due to its potential clinical significance.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/genética , Empatia/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Feminino , Genótipo , Humanos , Masculino , Autorrelato , Inquéritos e Questionários , Adulto Jovem
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