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1.
PLoS One ; 15(8): e0237032, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32790683

RESUMO

The behavioral activation system (BAS) and the behavioral inhibition system (BIS) have been proposed to relate to stable traits that predict inter-individual differences in motivation. Prior reports point dopamine (DA) pathways, mainly including ventral tegmental area (VTA) and substantia nigra (SN), implicate in subserving reward-related functions associated with BAS and inhibitory functions related with BIS. However, as an important factor that affects DA releasing, it remains an open question whether the ovarian hormones may also be related to BIS/BAS. Here, to investigate effects of the estradiol (E2) and progesterone (PROG) on BIS/BAS and related DA pathways, we employed a BIS/BAS scale and the resting-state functional magnetic resonance imaging (fMRI) during the late follicular phase (FP) and the mid-luteal phase (LP). On the behavioral level, when women had high PROG levels, their E2 levels were found positively correlated with BIS scores, but those women whose PROG levels were low, their E2 levels were negative correlation with BIS scores. On the neural level, we demonstrated BAS was related with the VTA pathway, included brain reward regions of nucleus accumbens (NAc) and orbitofrontal cortex (OFC). Meanwhile, the BIS was correlated with the SN-dorsolateral prefrontal cortex (dlPFC) pathway. ROI-based resting-state functional connectivity (RSFC) analyses further revealed that, RSFC between the SN and dlPFC was modulated by ovarian hormones. With higher PROG levels, increased E2 levels among women were accompanied by stronger RSFC of the SN-dlPFC, but when PROG levels were low, E2 levels were negatively correlated with the SN-dlPFC RSFC. These findings revealed a combined enhancement effect of E2 and PROG on BIS, and the SN-dlPFC pathway was mainly involved in this process.


Assuntos
Encéfalo/fisiologia , Dopamina/fisiologia , Inibição Psicológica , Motivação/fisiologia , Ovário/fisiologia , Adulto , Afeto/fisiologia , Encéfalo/diagnóstico por imagem , Neurônios Dopaminérgicos/fisiologia , Estradiol/fisiologia , Feminino , Neuroimagem Funcional , Humanos , Imagem por Ressonância Magnética , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Progesterona/fisiologia , Psicofisiologia , Substância Negra/diagnóstico por imagem , Substância Negra/fisiologia , Área Tegmentar Ventral/diagnóstico por imagem , Área Tegmentar Ventral/fisiologia , Adulto Jovem
2.
Proc Natl Acad Sci U S A ; 117(32): 19080-19091, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32747572

RESUMO

Every day, we are faced with the conflict between the temptation to cheat for financial gains and maintaining a positive image of ourselves as being a "good person." While it has been proposed that cognitive control is needed to mediate this conflict between reward and our moral self-image, the exact role of cognitive control in (dis)honesty remains elusive. Here we identify this role, by investigating the neural mechanism underlying cheating. We developed a task which allows for inconspicuously measuring spontaneous cheating on a trial-by-trial basis in the MRI scanner. We found that activity in the nucleus accumbens promotes cheating, particularly for individuals who cheat a lot, while a network consisting of posterior cingulate cortex, temporoparietal junction, and medial prefrontal cortex promotes honesty, particularly in individuals who are generally honest. Finally, activity in areas associated with cognitive control (anterior cingulate cortex and inferior frontal gyrus) helped dishonest participants to be honest, whereas it enabled cheating for honest participants. Thus, our results suggest that cognitive control is not needed to be honest or dishonest per se but that it depends on an individual's moral default.


Assuntos
Cognição , Decepção , Adolescente , Adulto , Mapeamento Encefálico , Tomada de Decisões , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Princípios Morais , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Recompensa , Adulto Jovem
3.
Proc Natl Acad Sci U S A ; 117(29): 17278-17287, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32631999

RESUMO

The prefrontal cortex (PFC) plays a critical role in curbing impulsive behavior, but the underlying circuit mechanism remains incompletely understood. Here we show that a subset of dorsomedial PFC (dmPFC) layer 5 pyramidal neurons, which project to the subthalamic nucleus (STN) of the basal ganglia, play a key role in inhibiting impulsive responses in a go/no-go task. Projection-specific labeling and calcium imaging showed that the great majority of STN-projecting neurons were preferentially active in no-go trials when the mouse successfully withheld licking responses, but lateral hypothalamus (LH)-projecting neurons were more active in go trials with licking; visual cortex (V1)-projecting neurons showed only weak task-related activity. Optogenetic activation and inactivation of STN-projecting neurons reduced and increased inappropriate licking, respectively, partly through their direct innervation of the STN, but manipulating LH-projecting neurons had the opposite effects. These results identify a projection-defined subtype of PFC pyramidal neurons as key mediators of impulse control.


Assuntos
Comportamento Impulsivo/fisiologia , Inibição Psicológica , Córtex Pré-Frontal/fisiologia , Células Piramidais/fisiologia , Animais , Gânglios da Base/fisiologia , Comportamento Animal/fisiologia , Interneurônios/fisiologia , Camundongos , Neurônios/fisiologia , Optogenética , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/patologia , Células Piramidais/patologia , Núcleo Subtalâmico/diagnóstico por imagem , Núcleo Subtalâmico/fisiologia , Córtex Visual
4.
Nat Commun ; 11(1): 3030, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32541779

RESUMO

Selectively attributing beliefs to specific agents is core to reasoning about other people and imagining oneself in different states. Evidence suggests humans might achieve this by simulating each other's computations in agent-specific neural circuits, but it is not known how circuits become agent-specific. Here we investigate whether agent-specificity adapts to social context. We train subjects on social learning tasks, manipulating the frequency with which self and other see the same information. Training alters the agent-specificity of prediction error (PE) circuits for at least 24 h, modulating the extent to which another agent's PE is experienced as one's own and influencing perspective-taking in an independent task. Ventromedial prefrontal myelin density, indexed by magnetisation transfer, correlates with the strength of this adaptation. We describe a frontotemporal learning network, which exploits relationships between different agents' computations. Our findings suggest that Self-Other boundaries are learnable variables, shaped by the statistical structure of social experience.


Assuntos
Córtex Pré-Frontal/fisiologia , Aprendizado Social , Adulto , Feminino , Humanos , Imaginação , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Bainha de Mielina/metabolismo , Valor Preditivo dos Testes , Córtex Pré-Frontal/diagnóstico por imagem , Comportamento Social , Substância Branca/diagnóstico por imagem , Substância Branca/fisiologia , Adulto Jovem
5.
Nat Commun ; 11(1): 2371, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32398675

RESUMO

Most real-world decisions involve a delicate balance between exploring unfamiliar alternatives and committing to the best known option. Previous work has shown that humans rely on different forms of uncertainty to negotiate this "explore-exploit" trade-off, yet the neural basis of the underlying computations remains unclear. Using fMRI (n = 31), we find that relative uncertainty is represented in right rostrolateral prefrontal cortex and drives directed exploration, while total uncertainty is represented in right dorsolateral prefrontal cortex and drives random exploration. The decision value signal combining relative and total uncertainty to compute choice is reflected in motor cortex activity. The variance of this signal scales with total uncertainty, consistent with a sampling mechanism for random exploration. Overall, these results are consistent with a hybrid computational architecture in which different uncertainty computations are performed separately and then combined by downstream decision circuits to compute choice.


Assuntos
Comportamento de Escolha/fisiologia , Comportamento Exploratório/fisiologia , Modelos Neurológicos , Córtex Pré-Frontal/fisiologia , Incerteza , Adolescente , Adulto , Análise de Variância , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Adulto Jovem
6.
Nat Commun ; 11(1): 2650, 2020 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-32461583

RESUMO

Although the feeling of stress is ubiquitous, the neural mechanisms underlying this affective experience remain unclear. Here, we investigate functional hippocampal connectivity throughout the brain during an acute stressor and use machine learning to demonstrate that these networks can specifically predict the subjective feeling of stress. During a stressor, hippocampal connectivity with a network including the hypothalamus (known to regulate physiological stress) predicts feeling more stressed, whereas connectivity with regions such as dorsolateral prefrontal cortex (associated with emotion regulation) predicts less stress. These networks do not predict a subjective state unrelated to stress, and a nonhippocampal network does not predict subjective stress. Hippocampal networks are consistent, specific to the construct of subjective stress, and broadly informative across measures of subjective stress. This approach provides opportunities for relating hypothesis-driven functional connectivity networks to clinically meaningful subjective states. Together, these results identify hippocampal networks that modulate the feeling of stress.


Assuntos
Conectoma , Emoções/fisiologia , Hipocampo/fisiologia , Rede Nervosa/fisiologia , Adulto , Conectoma/métodos , Conectoma/psicologia , Feminino , Hipocampo/diagnóstico por imagem , Humanos , Hipotálamo/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Masculino , Modelos Teóricos , Neurociências/métodos , Córtex Pré-Frontal/diagnóstico por imagem , Estresse Fisiológico/fisiologia , Adulto Jovem
7.
Am J Psychiatry ; 177(9): 844-854, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32375536

RESUMO

OBJECTIVE: The dual-pathway model has been proposed to explain the heterogeneity in symptoms of attention deficit hyperactivity disorder (ADHD) by two independent psychological pathways based on distinct brain circuits. The authors sought to test whether the hypothesized cognitive and motivational pathways have separable neural correlates. METHODS: In a longitudinal community-based cohort of 1,963 adolescents, the neuroanatomical correlates of ADHD were identified by a voxel-wise association analysis and then validated using an independent clinical sample (99 never-medicated patients with ADHD, 56 medicated patients with ADHD, and 267 healthy control subjects). The cognitive and motivational pathways were assessed by neuropsychological tests of working memory, intrasubject variability, stop-signal reaction time, and delay discounting. The associations were tested between the identified neuroanatomical correlates and both ADHD symptoms 2 years later and the polygenic risk score for ADHD. RESULTS: Gray matter volumes of both a prefrontal cluster and a posterior occipital cluster were negatively associated with inattention. Compared with healthy control subjects, never-medicated patients, but not medicated patients, had significantly lower gray matter volumes in these two clusters. Working memory and intrasubject variability were associated with the posterior occipital cluster, and delay discounting was independently associated with both clusters. The baseline gray matter volume of the posterior occipital cluster predicted the inattention symptoms in a 2-year follow-up and was associated with the genetic risk for ADHD. CONCLUSIONS: The dual-pathway model has both shared and separable neuroanatomical correlates, and the shared correlate in the occipital cortex has the potential to serve as an imaging trait marker of ADHD, especially the inattention symptom domain.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Sintomas Comportamentais , Cognição/fisiologia , Técnicas de Rastreamento Neuroanatômico/métodos , Lobo Occipital , Córtex Pré-Frontal , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Sintomas Comportamentais/diagnóstico , Sintomas Comportamentais/fisiopatologia , Ciências Biocomportamentais , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Humanos , Estudos Longitudinais , Masculino , Motivação/fisiologia , Neuroimagem/métodos , Testes Neuropsicológicos , Lobo Occipital/diagnóstico por imagem , Lobo Occipital/patologia , Tamanho do Órgão , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/patologia , Medição de Risco/métodos
8.
PLoS Biol ; 18(5): e3000605, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32453728

RESUMO

One of the most influential accounts of central orbitofrontal cortex-that it mediates behavioral flexibility-has been challenged by the finding that discrimination reversal in macaques, the classic test of behavioral flexibility, is unaffected when lesions are made by excitotoxin injection rather than aspiration. This suggests that the critical brain circuit mediating behavioral flexibility in reversal tasks lies beyond the central orbitofrontal cortex. To determine its identity, a group of nine macaques were taught discrimination reversal learning tasks, and its impact on gray matter was measured. Magnetic resonance imaging scans were taken before and after learning and compared with scans from two control groups, each comprising 10 animals. One control group learned discrimination tasks that were similar but lacked any reversal component, and the other control group engaged in no learning. Gray matter changes were prominent in posterior orbitofrontal cortex/anterior insula but were also found in three other frontal cortical regions: lateral orbitofrontal cortex (orbital part of area 12 [12o]), cingulate cortex, and lateral prefrontal cortex. In a second analysis, neural activity in posterior orbitofrontal cortex/anterior insula was measured at rest, and its pattern of coupling with the other frontal cortical regions was assessed. Activity coupling increased significantly in the reversal learning group in comparison with controls. In a final set of experiments, we used similar structural imaging procedures and analyses to demonstrate that aspiration lesion of central orbitofrontal cortex, of the type known to affect discrimination learning, affected structure and activity in the same frontal cortical circuit. The results identify a distributed frontal cortical circuit associated with behavioral flexibility.


Assuntos
Aprendizagem por Discriminação/fisiologia , Substância Cinzenta/fisiologia , Córtex Pré-Frontal/fisiologia , Adaptação Psicológica/fisiologia , Animais , Feminino , Substância Cinzenta/diagnóstico por imagem , Macaca , Imagem por Ressonância Magnética , Masculino , Córtex Pré-Frontal/diagnóstico por imagem
9.
PLoS One ; 15(4): e0230837, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32271789

RESUMO

Interrogation elicits anxiety in individuals under scrutiny regardless of their innocence, and thus, anxious responses to interrogation should be differentiated from deceptive behavior in practical lie detection settings. Despite its importance, not many empirical studies have yet been done to separate the effects of interrogation from the acts of lying or guilt state. The present fMRI study attempted to identify neural substrates of anxious responses under interrogation in either innocent or guilt contexts by developing a modified "Doubt" game. Participants in the guilt condition showed higher brain activations in the right central-executive network and bilateral basal ganglia. Regardless of the person's innocence, we observed higher activation of the salience, theory of mind and sensory-motor networks-areas associated with anxiety-related responses in the interrogative condition, compared to the waived conditions. We further explored two different types of anxious responses under interrogation-true detection anxiety in the guilty (true positive) and false detection anxiety in the innocent (false positive). Differential neural responses across these two conditions were captured at the caudate, thalamus, ventral anterior cingulate and ventromedial prefrontal cortex. We conclude that anxiety is a common neural response to interrogation, regardless of an individual's innocence, and that there are detectable differences in neural responses for true positive and false positive anxious responses under interrogation. The results of our study highlight a need to isolate complex cognitive processes involved in the deceptive acts from the emotional and regulatory responses to interrogation in lie detection schemes.


Assuntos
Ansiedade , Encéfalo/diagnóstico por imagem , Culpa , Detecção de Mentiras/psicologia , Adulto , Análise de Variância , Ansiedade/psicologia , Encéfalo/fisiologia , Feminino , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/fisiologia , Humanos , Aplicação da Lei , Imagem por Ressonância Magnética , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia
10.
PLoS Comput Biol ; 16(4): e1007791, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32282806

RESUMO

Widefield calcium imaging enables recording of large-scale neural activity across the mouse dorsal cortex. In order to examine the relationship of these neural signals to the resulting behavior, it is critical to demix the recordings into meaningful spatial and temporal components that can be mapped onto well-defined brain regions. However, no current tools satisfactorily extract the activity of the different brain regions in individual mice in a data-driven manner, while taking into account mouse-specific and preparation-specific differences. Here, we introduce Localized semi-Nonnegative Matrix Factorization (LocaNMF), a method that efficiently decomposes widefield video data and allows us to directly compare activity across multiple mice by outputting mouse-specific localized functional regions that are significantly more interpretable than more traditional decomposition techniques. Moreover, it provides a natural subspace to directly compare correlation maps and neural dynamics across different behaviors, mice, and experimental conditions, and enables identification of task- and movement-related brain regions.


Assuntos
Algoritmos , Mapeamento Encefálico/métodos , Cálcio/metabolismo , Processamento de Imagem Assistida por Computador/métodos , Córtex Pré-Frontal/diagnóstico por imagem , Animais , Cálcio/química , Camundongos , Córtex Pré-Frontal/química
11.
PLoS One ; 15(4): e0230666, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32271773

RESUMO

Although the connection between the left inferior frontal gyrus (LIFG) and the left superior temporal gyrus (LSTG) has been found to be essential for the comprehension of relative clause (RC) sentences, it remains unclear how the LIFG and the LSTG interact with each other, especially during the processing of Chinese RC sentences with different processing difficulty. This study thus conducted a 2 × 2 (modifying position × extraction position) factorial analyses to examine how these two factors influences regional brain activation. The results showed that, regardless of the modifying position, greater activation in the LIFG was consistently elicited in Chinese subject-extracted relative clauses (SRCs) with non-canonical word order than object-extracted relative clauses (ORCs) with canonical word order, implying that the LIFG subserving the ordering process primarily contributes to the processing of information with increased integration demands due to the non-canonical sequence. Moreover, the directional connection between the LIFG and the LSTG appeared to be modulated by different modifying positions. When the RC was at the subject-modifying position, the effective connectivity from the LIFG to the LSTG was dominantly activated for sentence comprehension; whereas when the RC was at the object-modifying position thus being more difficult, it might be the feedback mechanism from the LSTG back to the LIFG that took place in sentence processing. These findings reveal that brain activation in between the LIFG and the LSTG may be dynamically modulated by different processing difficulty and suggest the relative specialization but extensive collaboration involved in the LIFG and the LSTG for sentence comprehension.


Assuntos
Compreensão/fisiologia , Idioma , Rede Nervosa/fisiologia , Córtex Pré-Frontal/citologia , Leitura , Lobo Temporal/citologia , Adulto , Grupo com Ancestrais do Continente Asiático , Mapeamento Encefálico , Feminino , Humanos , Linguística , Imagem por Ressonância Magnética , Masculino , Rede Nervosa/anatomia & histologia , Rede Nervosa/diagnóstico por imagem , Córtex Pré-Frontal/anatomia & histologia , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Lobo Temporal/anatomia & histologia , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/fisiologia , Adulto Jovem
12.
J Neurosci ; 40(18): 3646-3656, 2020 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-32238480

RESUMO

As an important cognitive bias, the framing effect shows that our decision preferences are sensitive to the verbal description (i.e., frame) of options. This study focuses on the neural underpinnings of the social framing effect, which is based on decision-making regarding other people. A novel paradigm was used in which participants made a trade-off between economic benefits and the feelings of others. This decision was described as either a "harm" to, or "not helping," other persons in two conditions (Harm frame vs Help frame). Both human males and females were recruited. Participants behaved more prosocially for Harm frame compared with Help frame, resulting in a significant social framing effect. Using functional magnetic resonance imaging, Experiment 1 showed that the social framing effect was associated with stronger activation in the temporoparietal junction (TPJ), especially its right part. The functional connectivity between the right TPJ (rTPJ) and medial prefrontal cortex predicted the social framing effect on the group level. In Experiment 2, we used transcranial direct current stimulation to modulate the activity of the rTPJ and found that the social framing effect became more prominent under anodal (excitatory) stimulation, while the nonsocial framing effect elicited by the economic gain/loss gambling frame remained unaffected. The rTPJ results might be associated with moral conflicts modulated by the social consequences of an action or different levels of mentalizing with others under different frame conditions, but alternative interpretations are also worth noting. These findings could help elucidate the psychological mechanisms of the social framing effect.SIGNIFICANCE STATEMENT Previous studies have suggested that the framing effect is generated from an interaction between the amygdala and anterior cingulate cortex. This opinion, however, is based on findings from nonsocial framing tasks. Recent research has highlighted the importance of distinguishing between the social and nonsocial framing effects. The current study focuses on the social framing effect and finds out that the temporoparietal junction and its functional connectivity with the medial prefrontal cortex play a significant role. Additionally, modulating the activity of this region leads to changes in social (but not nonsocial) framing effect. Broadly speaking, these findings help understand the difference in neural mechanisms between social and nonsocial decision-making. Meanwhile, they might be illuminating to promote helping behavior in society.


Assuntos
Tonsila do Cerebelo/fisiologia , Tomada de Decisões/fisiologia , Imagem por Ressonância Magnética/métodos , Córtex Pré-Frontal/fisiologia , Estimulação Transcraniana por Corrente Contínua/métodos , Tonsila do Cerebelo/diagnóstico por imagem , Feminino , Humanos , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Adulto Jovem
13.
Proc Natl Acad Sci U S A ; 117(15): 8382-8390, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32238562

RESUMO

The human capacity to compute the likelihood that a decision is correct-known as metacognition-has proven difficult to study in isolation as it usually cooccurs with decision making. Here, we isolated postdecisional from decisional contributions to metacognition by analyzing neural correlates of confidence with multimodal imaging. Healthy volunteers reported their confidence in the accuracy of decisions they made or decisions they observed. We found better metacognitive performance for committed vs. observed decisions, indicating that committing to a decision may improve confidence. Relying on concurrent electroencephalography and hemodynamic recordings, we found a common correlate of confidence following committed and observed decisions in the inferior frontal gyrus and a dissociation in the anterior prefrontal cortex and anterior insula. We discuss these results in light of decisional and postdecisional accounts of confidence and propose a computational model of confidence in which metacognitive performance naturally improves when evidence accumulation is constrained upon committing a decision.


Assuntos
Julgamento , Córtex Pré-Frontal/fisiologia , Adulto , Tomada de Decisões , Eletroencefalografia , Feminino , Humanos , Masculino , Metacognição , Imagem Multimodal , Córtex Pré-Frontal/diagnóstico por imagem , Adulto Jovem
14.
Psychopharmacology (Berl) ; 237(6): 1873-1883, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32307560

RESUMO

BACKGROUND: The thalamus is a major target of dopaminergic projections and is densely connected with the prefrontal cortex. A better understanding of how dopamine changes thalamo-cortical communication may shed light on how dopamine supports cognitive function. Methylphenidate has been shown to facilitate cognitive processing and reduce connectivity between the thalamus and lateral prefrontal cortex. AIMS: The thalamus is a heterogeneous structure, and the present study sought to clarify how the intrinsic connections of thalamic sub-regions are differentially impacted by acute dopamine transporter blockade. METHODS: Sixty healthy volunteers were orally administered either 20 mg of methylphenidate (N = 29) or placebo (N = 31) in a double-blind, randomized, between-subject design. Multi-echo fMRI was used to assess intrinsic functional connectivity of sub-regions of the thalamus during a resting state scan. An N-back working-memory paradigm provided a measure of cognitive performance. RESULTS: Acute methylphenidate significantly reduced connectivity of the lateral prefrontal cortex with the motor and somatosensory sub-regions of the thalamus and reduced connectivity with the parietal and visual sub-regions at a trend level. Connectivity with the premotor, prefrontal, and temporal sub-regions was not impacted. The intrinsic connectivity between the thalamus and the lateral prefrontal cortex was not associated with working-memory performance. CONCLUSIONS: Methylphenidate decreases functional connections between the lateral prefrontal cortex and thalamus broadly, while sparing intrinsic connectivity with thalamic sub-regions involved with working-memory and language related processes. Collectively, our results suggest that the dopamine transporter regulates functional connections between the prefrontal cortex and non-cognitive areas of the thalamus.


Assuntos
Imagem por Ressonância Magnética/métodos , Memória de Curto Prazo/efeitos dos fármacos , Metilfenidato/administração & dosagem , Rede Nervosa/efeitos dos fármacos , Córtex Pré-Frontal/efeitos dos fármacos , Tálamo/efeitos dos fármacos , Adulto , Inibidores da Captação de Dopamina/administração & dosagem , Método Duplo-Cego , Feminino , Voluntários Saudáveis , Humanos , Masculino , Memória de Curto Prazo/fisiologia , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Tálamo/diagnóstico por imagem , Tálamo/fisiologia , Adulto Jovem
15.
Ann Neurol ; 87(6): 962-975, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32239535

RESUMO

OBJECTIVE: Subthalamic nucleus deep brain stimulation (STN-DBS) in Parkinson's disease (PD) not only stimulates focal target structures but also affects distributed brain networks. The impact this network modulation has on non-motor DBS effects is not well-characterized. By focusing on the affective domain, we systematically investigate the impact of electrode placement and associated structural connectivity on changes in depressive symptoms following STN-DBS, which have been reported to improve, worsen, or remain unchanged. METHODS: Depressive symptoms before and after STN-DBS surgery were documented in 116 patients with PD from 3 DBS centers (Berlin, Queensland, and Cologne). Based on individual electrode reconstructions, the volumes of tissue activated (VTAs) were estimated and combined with normative connectome data to identify structural connections passing through VTAs. Berlin and Queensland cohorts formed a training and cross-validation dataset used to identify structural connectivity explaining change in depressive symptoms. The Cologne data served as the test-set for which depressive symptom change was predicted. RESULTS: Structural connectivity was linked to depressive symptom change under STN-DBS. An optimal connectivity map trained on the Berlin cohort could predict changes in depressive symptoms in Queensland patients and vice versa. Furthermore, the joint training-set map predicted changes in depressive symptoms in the independent test-set. Worsening of depressive symptoms was associated with left prefrontal connectivity. INTERPRETATION: Fibers connecting the electrode with left prefrontal areas were associated with worsening of depressive symptoms. Our results suggest that for the left STN-DBS lead, placement impacting fibers to left prefrontal areas should be avoided to maximize improvement of depressive symptoms. ANN NEUROL 2020;87:962-975.


Assuntos
Estimulação Encefálica Profunda/efeitos adversos , Depressão/etiologia , Depressão/psicologia , Vias Neurais/diagnóstico por imagem , Córtex Pré-Frontal/diagnóstico por imagem , Núcleo Subtalâmico , Afeto , Idoso , Mapeamento Encefálico , Conectoma , Depressão/diagnóstico por imagem , Eletrodos Implantados , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuroimagem , Doença de Parkinson/complicações , Doença de Parkinson/psicologia , Doença de Parkinson/terapia , Estudos Retrospectivos , Núcleo Subtalâmico/diagnóstico por imagem , Tomografia Computadorizada por Raios X
16.
Psychiatry Res Neuroimaging ; 298: 111047, 2020 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-32114310

RESUMO

Electroacupuncture (EA) is a safe method for treating obesity; however, its underlying neural mechanisms remain unclear. We employed resting-state-functional-magnetic-resonance-imaging (RS-fMRI) and amplitude-of-low-frequency-fluctuation (ALFF) to investigate acute/long-term effects of EA on brain activity and resting-state-functional-connectivity (RSFC) in overweight/obesity subjects who received real/Sham stimulation. For acute effects, 26 and 19 overweight/obesity subjects were included in EA and Sham groups respectively. There were significant time effects on ALFF in the right insula (INS) and left dorsolateral-prefrontal-cortex (DLPFC) due to decreases/increases in INS/DLPFC in both groups. There were weaker positive RSFC between INS and supplementary-motor-area (SMA)/right DLPFC and weaker negative RSFC between INS and precuneus (PCUN); stronger negative RSFC between DLPFC and dorsomedial-prefrontal-cortex (DMPFC) in both groups. For long-term study, body-mass-index (BMI) had significant reduction in EA (n = 17) and Sham (15) groups; EA had higher BMI reduction than in Sham. There were significant time effects on ALFF in right ventrolateral-prefrontal-cortex (VLPFC) due to significant increases in EA group, and stronger positive RSFC between VLPFC and orbitofrontal-cortex and negative RSFC between VLPFC and left thalamus (THA) in both groups after long-term treatment. These findings suggest that changes in resting-activity and RSFC implicated in inhibitory-control, gastric-motility and satiety-control are associated with EA-induced weight-loss.


Assuntos
Córtex Cerebral/fisiopatologia , Conectoma , Eletroacupuntura , Avaliação de Resultados em Cuidados de Saúde , Sobrepeso/fisiopatologia , Sobrepeso/terapia , Tálamo/fisiopatologia , Perda de Peso , Adulto , Córtex Cerebral/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética , Obesidade/diagnóstico por imagem , Obesidade/fisiopatologia , Obesidade/terapia , Sobrepeso/diagnóstico por imagem , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiopatologia , Tálamo/diagnóstico por imagem
17.
Obesity (Silver Spring) ; 28(4): 696-705, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32144883

RESUMO

OBJECTIVE: The objective of this study was to test the feasibility of a combined intervention involving transcranial direct current stimulation (tDCS) on the dorsolateral prefrontal cortex (dlPFC) and cognitive training (CT). Short-term effects on food consumption, cognition, endocannabinoid (eCB) levels, and electroencephalogram (EEG) markers of future weight loss were explored. METHODS: Eighteen healthy volunteers with morbid obesity were randomized in a double-blind, placebo-controlled, parallel trial. Participants received sham or active tDCS plus CT for four consecutive days. Cognitive performance, daily food intake, and eCB blood samples were collected before and after the intervention; EEG data were gathered before and after daily training. RESULTS: The active tDCS + CT group reversed left-dominant frontal asymmetry and increased frontal coherence (FC) in the γ-band (30-45 Hz) after the intervention. The strength of the latter predicted BMI reduction. Additionally, a large intervention effect on food intake was shown in the active tDCS + CT group at follow-up (-339.6 ± 639 kcal on average), and there was a decrease of plasma eCB concentrations. CONCLUSIONS: dlPFC modulation through tDCS + CT is an effective tool to restore right dominance of the dlPFC and enhance FC in patients with morbid obesity. Moreover, the effect of the strength of FC on BMI suggests that the interhemispheric FC at the dlPFC is functionally relevant for the efficient regulation of food choice.


Assuntos
Obesidade Mórbida/genética , Córtex Pré-Frontal/diagnóstico por imagem , Estimulação Transcraniana por Corrente Contínua/métodos , Adulto , Método Duplo-Cego , Ingestão de Energia , Feminino , Voluntários Saudáveis , Humanos , Masculino
18.
F1000Res ; 92020.
Artigo em Inglês | MEDLINE | ID: mdl-32161644

RESUMO

Even apparently simple choices, like selecting a dessert in a pastry shop, involve options characterized by multiple motivationally relevant attributes. Neuroeconomic research suggests that the human brain may track the subjective value of such options, allowing disparate reward-predictive information to be compared in a common currency. However, the brain mechanisms involved in identifying value-predictive features and combining these to assess the value of each decision option remain unclear. Here, we review recent evidence from studies of multi-attribute decision-making in people with focal frontal lobe damage and in healthy people undergoing functional magnetic resonance imaging. This work suggests that ventromedial and lateral prefrontal cortex and orbitofrontal cortex are important for forming value judgments under conditions of complexity. We discuss studies supporting the involvement of these regions in selecting among and evaluating option attributes during value judgment and decision-making and when learning from reward feedback. These findings are consistent with roles for these regions in guiding value construction. They argue for a more nuanced understanding of how ventral and lateral prefrontal cortex contribute to discovering and recognizing value, processes that are required under the complex conditions typical of many everyday decisions.


Assuntos
Tomada de Decisões , Lobo Frontal/fisiologia , Lobo Frontal/fisiopatologia , Córtex Pré-Frontal/fisiologia , Córtex Pré-Frontal/fisiopatologia , Lobo Frontal/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética , Córtex Pré-Frontal/diagnóstico por imagem , Recompensa
19.
Nat Commun ; 11(1): 1230, 2020 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-32144259

RESUMO

Experiencing events as controllable is essential for human well-being. Based on classic psychological theory, we test how internal control beliefs impact the affective valuation of task outcomes, neural dynamics and ensuing behavioral preferences. In three consecutive studies we show that dynamics in positive affect increase, with a qualitative shift towards self-evaluative pride, when agents believe they caused a given outcome. We demonstrate that these outcomes engage brain networks processing self-referential information in the cortical midline. Here, activity in the ventromedial prefrontal cortex tracks outcome valence regarding both success as well as internal control, and covaries with positive affect in response to outcomes. These affective dynamics also relate to increased functional coupling between the ventral striatum and cortical midline structures. Finally, we show that pride predicts preferences for control, even at monetary costs. Our investigations extend recent models of positive affect and well-being, and emphasize that control beliefs drive intrinsic motivation.


Assuntos
Modelos Psicológicos , Motivação/fisiologia , Córtex Pré-Frontal/fisiologia , Recompensa , Estriado Ventral/fisiologia , Adolescente , Adulto , Afeto/fisiologia , Mapeamento Encefálico , Tomada de Decisões/fisiologia , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Estriado Ventral/diagnóstico por imagem , Adulto Jovem
20.
Psychopharmacology (Berl) ; 237(6): 1813-1826, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32162103

RESUMO

RATIONALE: Excessive fear and anxiety, coupled with corticolimbic dysfunction, are core features of stress- and trauma-related psychopathology, such as posttraumatic stress disorder (PTSD). Interestingly, low doses of ∆9-tetrahydrocannabinol (THC) can produce anxiolytic effects, reduce threat-related amygdala activation, and enhance functional coupling between the amygdala and medial prefrontal cortex and adjacent rostral cingulate cortex (mPFC/rACC) during threat processing in healthy adults. Together, these findings suggest the cannabinoid system as a potential pharmacological target in the treatment of excess fear and anxiety. However, the effects of THC on corticolimbic functioning in response to threat have not be investigated in adults with trauma-related psychopathology. OBJECTIVE: To address this gap, the present study tests the effects of an acute low dose of THC on corticolimbic responses to threat in three groups of adults: (1) non-trauma-exposed healthy controls (HC; n = 25), (2) trauma-exposed adults without PTSD (TEC; n = 27), and (3) trauma-exposed adults with PTSD (n = 19). METHODS: Using a randomized, double-blind, placebo-controlled, between-subjects design, 71 participants were randomly assigned to receive either THC or placebo (PBO) and subsequently completed a well-established threat processing paradigm during functional magnetic resonance imaging. RESULTS: In adults with PTSD, THC lowered threat-related amygdala reactivity, increased mPFC activation during threat, and increased mPFC-amygdala functional coupling. CONCLUSIONS: These preliminary data suggest that THC modulates threat-related processing in trauma-exposed individuals with PTSD, which may prove advantageous as a pharmacological approach to treating stress- and trauma-related psychopathology.


Assuntos
Tonsila do Cerebelo/efeitos dos fármacos , Dronabinol/farmacologia , Medo/efeitos dos fármacos , Córtex Pré-Frontal/efeitos dos fármacos , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Canabinoides/farmacologia , Canabinoides/uso terapêutico , Método Duplo-Cego , Dronabinol/uso terapêutico , Medo/psicologia , Feminino , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Córtex Pré-Frontal/diagnóstico por imagem , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Transtornos de Estresse Pós-Traumáticos/psicologia
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