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AIM: While conservatism bias refers to the human need for more evidence for decision-making than rational thinking expects, the jumping to conclusions (JTC) bias refers to the need for less evidence among individuals with schizophrenia/delusion compared to healthy people. Although the hippocampus-midbrain-striatal aberrant salience system and the salience, default mode (DMN), and frontoparietal networks ("triple networks") are implicated in delusion/schizophrenia pathophysiology, the associations between conservatism/JTC and these systems/networks are unclear. METHODS: Thirty-seven patients with schizophrenia and 33 healthy controls performed the beads task, with large and small numbers of bead draws to decision (DTD) indicating conservatism and JTC, respectively. We performed independent component analysis (ICA) of resting functional magnetic resonance imaging (fMRI) data. For systems/networks above, we investigated interactions between diagnosis and DTD, and main effects of DTD. We similarly applied ICA to structural and diffusion MRI to explore the associations between DTD and gray/white matter. RESULTS: We identified a significant main effect of DTD with functional connectivity between the striatum and DMN, which was negatively correlated with delusion severity in patients, indicating that the greater the anti-correlation between these networks, the stronger the JTC and delusion. We further observed the main effects of DTD on a gray matter network resembling the DMN, and a white matter network connecting the functional and gray matter networks (all P < 0.05, family-wise error [FWE] correction). Function and gray/white matter showed no significant interactions. CONCLUSION: Our results support the novel association of conservatism and JTC biases with aberrant salience and default brain mode.
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Tomada de Decisões , Rede de Modo Padrão , Delusões , Imageamento por Ressonância Magnética , Esquizofrenia , Humanos , Adulto , Rede de Modo Padrão/fisiopatologia , Rede de Modo Padrão/diagnóstico por imagem , Masculino , Feminino , Esquizofrenia/fisiopatologia , Esquizofrenia/diagnóstico por imagem , Delusões/fisiopatologia , Delusões/diagnóstico por imagem , Tomada de Decisões/fisiologia , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiopatologia , Substância Branca/diagnóstico por imagem , Substância Branca/fisiopatologia , Substância Branca/patologia , Pessoa de Meia-Idade , Adulto Jovem , Corpo Estriado/diagnóstico por imagem , Corpo Estriado/fisiopatologia , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/fisiopatologia , Substância Cinzenta/patologiaRESUMO
Social-anxiety disorder involves a fear of embarrassing oneself in the presence of others. Taijin-kyofusho (TKS), a subtype common in East Asia, additionally includes a fear of embarrassing others. TKS individuals are hypersensitive to others' feelings and worry that their physical or behavioral defects humiliate others. To explore the underlying neurocognitive mechanisms, we compared TKS ratings with questionnaire-based empathic disposition, cognitive flexibility (set-shifting), and empathy-associated brain activity in 23 Japanese adults. During 3-tesla functional MRI, subjects watched video clips of badly singing people who expressed either authentic embarrassment (EMBAR) or hubristic pride (PRIDE). We expected the EMBAR singers to embarrass the viewers via emotion-sharing involving affective empathy (affEMP), and the PRIDE singers to embarrass via perspective-taking involving cognitive empathy (cogEMP). During affEMP (EMBAR > PRIDE), TKS scores correlated positively with dispositional affEMP (personal-distress dimension) and with amygdala activity. During cogEMP (EMBAR < PRIDE), TKS scores correlated negatively with cognitive flexibility and with activity of the posterior superior temporal sulcus/temporoparietal junction (pSTS/TPJ). Intersubject correlation analysis implied stronger involvement of the anterior insula, inferior frontal gyrus, and premotor cortex during affEMP than cogEMP and stronger involvement of the medial prefrontal cortex, posterior cingulate cortex, and pSTS/TPJ during cogEMP than affEMP. During cogEMP, the whole-brain functional connectivity was weaker the higher the TKS scores. The observed imbalance between affEMP and cogEMP, and the disruption of functional brain connectivity, likely deteriorate cognitive processing during embarrassing situations in persons who suffer from other-oriented social anxiety dominated by empathic embarrassment.
Assuntos
Fobia Social/psicologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Mapeamento Encefálico , Cognição , Constrangimento , Emoções , Empatia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Fobia Social/diagnóstico por imagem , Fobia Social/fisiopatologia , Adulto JovemRESUMO
Although previous studies have suggested the involvement of dopamine (DA) and noradrenaline (NA) neurotransmissions in the autism spectrum disorder (ASD) pathophysiology, few studies have examined these neurotransmissions in individuals with ASD in vivo. Here, we investigated DA D1 receptor (D1R) and noradrenaline transporter (NAT) binding in adults with ASD (n = 18) and neurotypical controls (n = 20) by utilizing two different PET radioligands, [11C]SCH23390 and (S,S)-[18F]FMeNER-D2, respectively. We found no significant group differences in DA D1R (striatum, anterior cingulate cortex, and temporal cortex) or NAT (thalamus and pons) binding. However, in the ASD group, there were significant negative correlations between DA D1R binding (striatum, anterior cingulate cortex and temporal cortex) and the "attention to detail" subscale score of the Autism Spectrum Quotient. Further, there was a significant positive correlation between DA D1R binding (temporal cortex) and emotion perception ability assessed by the neurocognitive battery. Associations of NAT binding with empathic abilities and executive function were found in controls, but were absent in the ASD group. Although a lack of significant group differences in binding might be partly due to the heterogeneity of ASD, our results indicate that central DA and NA function might play certain roles in the clinical characteristics of ASD.
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Transtorno do Espectro Autista/metabolismo , Encéfalo/metabolismo , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/metabolismo , Receptores de Dopamina D1/metabolismo , Adulto , Humanos , Masculino , Tomografia por Emissão de PósitronsRESUMO
Although fear and anxiety have gradually become a shared experience in the time of COVID-19, few studies have examined its content from historical, cultural, and phenomenological perspectives concerning the self-awareness and alterity. We discuss the development of the ubiquitous nature of Taijin-kyofusho (TKS), a subtype of social anxiety disorder (SAD) originated and considered culturally-bound in the 1930s Japan involving fear of offending or displeasing other people. Considering the historical processes of disease classification, advances in cognitive neurosciences, and the need to better understand the content of suffering, psychiatric nosology for SAD still appears controversial and requires further investigations.
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COVID-19/psicologia , Fobia Social/psicologia , Manual Diagnóstico e Estatístico de Transtornos Mentais , História do Século XX , Humanos , Japão/etnologia , Fobia Social/história , SARS-CoV-2RESUMO
Intergroup bias, which is the tendency to behave more positively toward an in-group member than toward an out-group member, is pervasive in real life. In particular, intergroup bias in trust decisions substantially influences multiple areas of life and thus better understanding of this tendency can provide significant insights into human social behavior. Although previous functional magnetic resonance imaging studies showed the involvement of the right temporoparietal junction (TPJ) in intergroup trust bias, a causal relationship between the two has rarely been explored. By combining repetitive transcranial magnetic stimulation and a newly developed trust game task, we investigated the causal role of the right TPJ in intergroup bias in trust decisions. In the trust game task, the counterpart's group membership (in-group or out-group) and reciprocity were manipulated. We applied either neuronavigated inhibitory continuous theta burst stimulation (cTBS) or sham stimulation over the right TPJ before performing the trust game task in healthy volunteers. After the sham stimulation, the participants' degrees of investments with in-group members were significantly higher than those with out-group members. However, after cTBS to the right TPJ, this difference was not observed. The current results extend previous findings by showing that the causal roles of the right TPJ can be observed in intergroup bias in trust decisions. Our findings add to our understanding of the mechanisms of human social behavior.
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Tomada de Decisões/fisiologia , Lobo Parietal/diagnóstico por imagem , Lobo Parietal/fisiologia , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/fisiologia , Confiança/psicologia , Adulto , Mapeamento Encefálico , Eletroencefalografia , Jogos Experimentais , Humanos , Individualidade , Inibição Psicológica , Imageamento por Ressonância Magnética , Masculino , Neuronavegação , Tempo de Reação , Comportamento Social , Ritmo Teta , Estimulação Magnética Transcraniana , Adulto JovemRESUMO
People are often influenced by past costs in their current decision-making, thus succumbing to a well-known bias recognized as the sunk cost effect. A recent study showed that the sunk cost effect is attenuated in individuals with autism spectrum disorder (ASD). However, the study only addressed one situation of utilization decision by focusing on the choice between similar attractive alternatives with different levels of sunk costs. Thus, it remains unclear how individuals with ASD behave under sunk costs in different types of decision situations, particularly progress decisions, in which the decision-maker allocates additional resources to an initially chosen alternative. The sunk cost effect in progress decisions was estimated using an economic task designed to assess the effect of the past investments on current decision-making. Twenty-four individuals with ASD and 21 age-, sex-, smoking status-, education-, and intelligence quotient-level-matched typical development (TD) subjects were evaluated. The TD participants were more willing to make the second incremental investment if a previous investment was made, indicating that their decisions were influenced by sunk costs. However, unlike the TD group, the rates of investments were not significantly increased after prior investments in the ASD group. The results agree with the previous evidence of a reduced sensitivity to context stimuli in individuals with ASD and help us obtain a broader picture of the impact of sunk costs on their decision-making. Our findings will contribute to a better understanding of ASD and may be useful in addressing practical implications of their socioeconomic behavior.
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Transtorno do Espectro Autista/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Tomada de Decisões/fisiologia , Adulto , Transtorno do Espectro Autista/complicações , Disfunção Cognitiva/etiologia , Feminino , Humanos , Acontecimentos que Mudam a Vida , Masculino , Adulto JovemRESUMO
Excessive gaming can impair both mental and physical health, drawing widespread public and clinical attention, especially among young generations. People are now more exposed to gaming-related content on social media than before, and this exposure may have a significant impact on their behavior. However, the neural mechanisms underlying this effect remain unexplored. Using functional magnetic resonance imaging (fMRI), this study aimed to investigate the neural activity induced by gaming-related content on social media among young adults casually playing online games. While being assessed by fMRI, the participants watched gaming-related videos and neutral (nongaming) videos on social media. The gaming-related cues significantly activated several brain areas, including the medial prefrontal cortex, posterior cingulate cortex, hippocampus, thalamus, superior/middle temporal gyrus, precuneus and occipital regions, compared with the neutral cues. Additionally, the participants' gaming desire levels positively correlated with a gaming-related cue-induced activation in the left orbitofrontal cortex and the right superior temporal gyrus. These findings extend previous studies on gaming cues and provide useful information to elucidate the effects of gaming-related content on social media in young adults. Continued research using real-world gaming cues may help improve our understanding of promoting gaming habits and provide support to individuals vulnerable to gaming addiction.
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Mapeamento Encefálico , Encéfalo , Sinais (Psicologia) , Imageamento por Ressonância Magnética , Mídias Sociais , Jogos de Vídeo , Humanos , Adulto Jovem , Masculino , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Feminino , Adulto , Comportamento Aditivo/fisiopatologia , AdolescenteRESUMO
Excessive gameplay can have negative effects on both mental and physical health, especially among young people. Nowadays, social media platforms are bombarding users with gaming-related content daily. Understanding the effect of this content on people's behavior is essential to gain insight into problematic gaming habits. However, this issue is yet to be studied extensively. In this study, we examined how gaming-related content on social media affects young adults explicitly and implicitly. We studied 25 healthy young adults (average age 21.5 ± 2.2) who played online games casually and asked them to report their gaming desire. We also conducted an implicit association test (IAT) to measure their implicit attitudes toward gaming-related content. We also investigated the relationship between these measures and various psychological factors, such as personality traits, self-efficacy, impulsiveness, and cognitive flexibility. The results revealed that participants had a higher explicit gaming desire when exposed to gaming-related cues on social media than neutral cues. They also had a robust positive implicit attitude toward gaming-related content on social media. Explicit gaming desire was positively correlated with neuroticism levels. Furthermore, the IAT effect was negatively correlated with self-efficacy and cognitive flexibility levels. However, there were no significant correlations between explicit gaming desire/IAT effect and impulsiveness levels. These findings suggest that gaming-related content on social media can affect young adults' behavior both explicitly and implicitly, highlighting the need for further research to prevent gaming addiction in vulnerable individuals.
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Theory of mind (ToM), which is the ability to infer and reason about others' mental states, plays a key role in successful social interactions. Previous studies have shown that cognitive flexibility (CF), which refers to the ability to adequately switch between different perspectives, is linked to ToM performance in a variety of experimental tasks. However, the mechanisms of the association between CF and ToM is still largely unknown. Here, we investigated the relation of CF with neural activity during ToM processing in 26 healthy male adults using a functional magnetic resonance imaging task of moving shapes in social patterns. The CF abilities were estimated using the self-report Cognitive Flexibility Scale. Diverse brain areas, including the middle frontal gyrus (MFG), inferior frontal gyrus, amygdala, precuneus, and temporoparietal junction (TPJ), were activated during ToM processing. In these areas, individual differences in CF abilities were associated with the strength of neural activity in the right MFG and TPJ. These findings highlight the notion that cognitive ability to switch between different perspectives according to a changing environment is crucial for the attribution of mental state to others, and suggest that the right MFG and TPJ are deserving of further examination for the development of new therapies to improve social cognition in clinical populations.
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Teoria da Mente , Adulto , Humanos , Masculino , Teoria da Mente/fisiologia , Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Cognição/fisiologia , Imageamento por Ressonância Magnética/métodosRESUMO
Although mitigating burnout has long been a pressing issue in healthcare, recent global disasters, including the COVID-19 pandemic and wars, have exacerbated this problem. Medical professionals are frequently exposed to diverse job-induced distress; furthermore, the importance of people's sense of coherence (SOC) over work has been addressed to better deal with burnout. However, the neural mechanisms underlying SOC in medical professionals are not sufficiently investigated. In this study, the intrinsic fractional amplitude of low-frequency fluctuations (fALFF) were measured as an indicator of regional brain spontaneous activity using resting-state functional magnetic resonance imaging in registered nurses. The associations between participants' SOC levels and the fALFF values within brain regions were subsequently explored. The SOC scale scores were positively correlated with fALFF values in the right superior frontal gyrus (SFG) and the left inferior parietal lobule. Furthermore, the SOC levels of the participants mediated the link between their fALFF values in the right SFG and the depersonalization dimension of burnout. The results deepened the understanding of the counter role of SOC on burnout in medical professionals and may provide practical insights for developing efficient interventions.
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COVID-19 , Senso de Coerência , Humanos , Pandemias , Córtex Pré-Frontal , Esgotamento PsicológicoRESUMO
We examined the neural underpinnings of the effects of mindfulness on anxiety in anorexia nervosa using functional magnetic resonance imaging in 21 anorexia patients. We used a functional magnetic resonance imaging task designed to induce weight-related anxiety and asked participants to regulate their anxiety either using or not using an acceptance strategy. Our results showed reduced activity in the amygdala, anterior cingulate cortex, putamen, caudate, orbital gyrus, middle frontal gyrus, posterior cingulate cortex and precuneus following a mindfulness-based intervention. The present study provides new insight regarding the neural mechanisms underlying the effect of mindfulness-based intervention in ameliorating anorexia nervosa.
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Individuals with autism spectrum disorder (ASD) often show limited empathy (poor recognition of others' emotions) and high alexithymia (poor recognition of own emotions and external thinking), which can negatively impact their social functioning. Previous experimental studies suggest that alterations in cognitive flexibility play key roles in the development of these characteristics in ASD. However, the underlying neural mechanisms that link cognitive flexibility and empathy/alexithymia are still largely unknown. In this study, we examined the neural correlates of cognitive flexibility via functional magnetic resonance imaging during perceptual task-switching in typical development (TD) adults and adults with ASD. We also investigated associations between regional neural activity and psychometric empathy and alexithymia scores among these populations. In the TD group, stronger activation of the left middle frontal gyrus was associated with better perceptual switching and greater empathic concern. Among individuals with ASD, stronger activation of the left inferior frontal gyrus was associated with better perceptual switching, greater empathy, and lower alexithymia. These findings will contribute to develop a better understanding of social cognition, and could be informative for the development of new ASD therapies.
Assuntos
Transtorno do Espectro Autista , Empatia , Adulto , Humanos , Sintomas Afetivos/diagnóstico por imagem , Sintomas Afetivos/etiologia , Transtorno do Espectro Autista/diagnóstico por imagem , Transtorno do Espectro Autista/psicologia , Emoções/fisiologia , Lobo Frontal , Imageamento por Ressonância MagnéticaRESUMO
Increased excitatory neuronal tones have been implicated in autism, but its mechanism remains elusive. The amplified glutamate signals may arise from enhanced glutamatergic circuits, which can be affected by astrocyte activation and suppressive signaling of dopamine neurotransmission. We tested this hypothesis using magnetic resonance spectroscopy and positron emission tomography scan with 11C-SCH23390 for dopamine D1 receptors in the anterior cingulate cortex (ACC). We enrolled 18 male adults with high-functioning autism and 20 typically developed (TD) male subjects. The autism group showed elevated glutamate, glutamine, and myo-inositol (mI) levels compared with the TD group (p = 0.045, p = 0.044, p = 0.030, respectively) and a positive correlation between glutamine and mI levels in the ACC (r = 0.54, p = 0.020). In autism and TD groups, ACC D1 receptor radioligand binding was negatively correlated with ACC glutamine levels (r = - 0.55, p = 0.022; r = - 0.58, p = 0.008, respectively). The enhanced glutamate-glutamine metabolism might be due to astroglial activation and the consequent reinforcement of glutamine synthesis in autistic brains. Glutamine synthesis could underly the physiological inhibitory control of dopaminergic D1 receptor signals. Our findings suggest a high neuron excitation-inhibition ratio with astrocytic activation in the etiology of autism.
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Transtorno Autístico , Glutamina , Masculino , Adulto , Humanos , Glutamina/metabolismo , Ácido Glutâmico/metabolismo , Transtorno Autístico/metabolismo , Astrócitos/metabolismo , Dopamina/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/metabolismoRESUMO
Brain functional states are established by functional connectivities between brain regions. In experienced meditators (13 Tibetan Buddhists, 15 QiGong, 14 Sahaja Yoga, 14 Ananda Marga Yoga, 15 Zen), 19-channel EEG was recorded before, during and after that meditation exercise which their respective tradition regards as route to the most desirable meditative state. The head surface EEG data were recomputed (sLORETA) into 19 cortical regional source model time series. All 171 functional connectivities between regions were computed as 'lagged coherence' for the eight EEG frequency bands (delta through gamma). This analysis removes ambiguities of localization, volume conduction-induced inflation of coherence, and reference-dependence. All significant differences (corrected for multiple testing) between meditation compared to no-task rest before and after meditation showed lower coherence during meditation, in all five traditions and eight (inhibitory as well as excitatory) frequency bands. Conventional coherence between the original head surface EEG time series very predominantly also showed reduced coherence during meditation. The topography of the functional connectivities was examined via PCA-based computation of principal connectivities. When going into and out of meditation, significantly different connectivities revealed clearly different topographies in the delta frequency band and minor differences in the beta-2 band. The globally reduced functional interdependence between brain regions in meditation suggests that interaction between the self process functions is minimized, and that constraints on the self process by other processes are minimized, thereby leading to the subjective experience of non-involvement, detachment and letting go, as well as of all-oneness and dissolution of ego borders during meditation.
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Córtex Cerebral/fisiologia , Eletroencefalografia , Meditação , Adulto , Humanos , Pessoa de Meia-IdadeRESUMO
Experienced Qigong meditators who regularly perform the exercises "Thinking of Nothing" and "Qigong" were studied with multichannel EEG source imaging during their meditations. The intracerebral localization of brain electric activity during the two meditation conditions was compared using sLORETA functional EEG tomography. Differences between conditions were assessed using t statistics (corrected for multiple testing) on the normalized and log-transformed current density values of the sLORETA images. In the EEG alpha-2 frequency, 125 voxels differed significantly; all were more active during "Qigong" than "Thinking of Nothing," forming a single cluster in parietal Brodmann areas 5, 7, 31, and 40, all in the right hemisphere. In the EEG beta-1 frequency, 37 voxels differed significantly; all were more active during "Thinking of Nothing" than "Qigong," forming a single cluster in prefrontal Brodmann areas 6, 8, and 9, all in the left hemisphere. Compared to combined initial-final no-task resting, "Qigong" showed activation in posterior areas whereas "Thinking of Nothing" showed activation in anterior areas. The stronger activity of posterior (right) parietal areas during "Qigong" and anterior (left) prefrontal areas during "Thinking of Nothing" may reflect a predominance of self-reference, attention and input-centered processing in the "Qigong" meditation, and of control-centered processing in the "Thinking of Nothing" meditation.
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Mapeamento Encefálico , Ondas Encefálicas/fisiologia , Encéfalo/fisiologia , Exercícios Respiratórios , Imaginação/fisiologia , Meditação , Adulto , Encéfalo/irrigação sanguínea , Eletroencefalografia , Feminino , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Descanso/fisiologia , Fatores de TempoRESUMO
Occupational burnout has become a pervasive problem, especially among medical professionals who are highly vulnerable to burnout. Since the beginning of the COVID-19 pandemic, medical professionals have faced greater levels of stress. It is critical to increase our understanding of the neurobiological mechanisms of burnout among medical professionals for the benefit of healthcare systems. Therefore, in this study, we investigated structural brain correlates of burnout severity in medical professionals using a voxel-based morphometric technique. Nurses in active service underwent structural magnetic resonance imaging. Two core dimensions of burnout, namely, emotional exhaustion and depersonalization, were assessed using self-reported psychological questionnaires. Levels of emotional exhaustion were found to be negatively correlated with gray matter (GM) volumes in the bilateral ventromedial prefrontal cortex (vmPFC) and left insula. Moreover, levels of depersonalization were negatively correlated with GM volumes in the left vmPFC and left thalamus. Altogether, these findings contribute to a better understanding of the neural mechanisms of burnout and may provide helpful insights for developing effective interventions for medical professionals.
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Encéfalo/diagnóstico por imagem , Esgotamento Profissional/diagnóstico por imagem , Adulto , COVID-19 , Córtex Cerebral/diagnóstico por imagem , Despersonalização , Emoções , Feminino , Substância Cinzenta/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Enfermeiras e Enfermeiros , Pandemias , Córtex Pré-Frontal/diagnóstico por imagem , Autorrelato , Inquéritos e Questionários , Tálamo/diagnóstico por imagem , Adulto JovemRESUMO
Groups are essential elements of society, and humans, by nature, commonly manifest intergroup bias (i.e., behave more positively toward an ingroup member than toward an outgroup member). Despite the growing evidence of various types of altered decision-making in individuals with autism spectrum disorder (ASD), their behavior under the situation involving group membership remains largely unexplored. By modifying a third-party punishment paradigm, we investigated intergroup bias in individuals with ASD and typical development (TD). In our experiment, participants who were considered as the third party observed a dictator game wherein proposers could decide how to distribute a provided amount of money while receivers could only accept unconditionally. Participants were confronted with two different group situations: the proposer was an ingroup member and the recipient was an outgroup member (IN/OUT condition) or the proposer was an outgroup member and the recipient was an ingroup member (OUT/IN condition). Participants with TD punished proposers more severely when violating social norms in the OUT/IN condition than in IN/OUT condition, indicating that their decisions were influenced by the intergroup context. This intergroup bias was attenuated in individuals with ASD. Our findings deepen the understanding of altered decision-making and socioeconomic behaviors in individuals with ASD.
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People make flexible decisions across a wide range of contexts to resolve social or moral conflicts. Individuals with autism spectrum disorder (ASD) frequently report difficulties in such behaviors, which hinders the flexibility in changing strategies during daily activities or adjustment of perspective during communication. However, the underlying mechanisms of this issue are insufficiently understood. This study aimed to investigate decision flexibility in ASD using a functional magnetic resonance imaging task that involved recognizing and resolving two types of moral dilemmas: cost-benefit analysis (CBA) and mitigating inevitable misconducts (MIM). The CBA session assessed the participants' pitting of result-oriented outcomes against distressful harmful actions, whereas the MIM session assessed their pitting of the extenuation of a criminal sentence against a sympathetic situation of defendants suffering from violence or disease. The behavioral outcome in CBA-related flexibility was significantly lower in the ASD group compared to that of the typical development group. In the corresponding CBA contrast, activation in the left inferior frontal gyrus was lower in the ASD group. Meanwhile, in the MIM-related flexibility, there were no significant group differences in behavioral outcome or brain activity. Our findings add to our understanding of flexible decision-making in ASD.
Assuntos
Transtorno do Espectro Autista , Imageamento por Ressonância Magnética , Transtorno do Espectro Autista/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Humanos , Imageamento por Ressonância Magnética/métodos , Princípios MoraisRESUMO
Neural activity is known to oscillate within discrete frequency bands and the synchronization between these rhythms is hypothesized to underlie information integration in the brain. Since strict synchronization is only possible for harmonic frequencies, a recent theory proposes that the interaction between different brain rhythms is facilitated by transient harmonic frequency arrangements. In this line, it has been recently shown that the transient occurrence of 2:1 harmonic cross-frequency relationships between alpha and theta rhythms (i.e. falpha ≈ 12 Hz; ftheta ≈ 6 Hz) is enhanced during effortful cognition. In this study, we tested whether achieving a state of 'mental emptiness' during meditation is accompanied by a relative decrease in the occurrence of 2:1 harmonic cross-frequency relationships between alpha and theta rhythms. Continuous EEG recordings (19 electrodes) were obtained from 43 highly experienced meditators during meditation practice, rest and an arithmetic task. We show that the occurrence of transient alpha:theta 2:1 harmonic relationships increased linearly from a meditative to an active cognitive processing state (i.e. meditation < rest < arithmetic task). It is argued that transient EEG cross-frequency arrangements that prevent alpha:theta cross-frequency coupling could facilitate the experience of 'mental emptiness' by avoiding the interaction between the memory and executive components of cognition.