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1.
Cell ; 177(4): 986-998.e15, 2019 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-30982599

RESUMO

By observing their social partners, primates learn about reward values of objects. Here, we show that monkeys' amygdala neurons derive object values from observation and use these values to simulate a partner monkey's decision process. While monkeys alternated making reward-based choices, amygdala neurons encoded object-specific values learned from observation. Dynamic activities converted these values to representations of the recorded monkey's own choices. Surprisingly, the same activity patterns unfolded spontaneously before partner's choices in separate neurons, as if these neurons simulated the partner's decision-making. These "simulation neurons" encoded signatures of mutual-inhibitory decision computation, including value comparisons and value-to-choice conversions, resulting in accurate predictions of partner's choices. Population decoding identified differential contributions of amygdala subnuclei. Biophysical modeling of amygdala circuits showed that simulation neurons emerge naturally from convergence between object-value neurons and self-other neurons. By simulating decision computations during observation, these neurons could allow primates to reconstruct their social partners' mental states.


Assuntos
Tonsila do Cerebelo/metabolismo , Tonsila do Cerebelo/fisiologia , Tomada de Decisões/fisiologia , Animais , Comportamento Animal/fisiologia , Comportamento de Escolha/fisiologia , Relações Interpessoais , Aprendizagem/fisiologia , Macaca mulatta/fisiologia , Masculino , Neurônios/metabolismo , Neurônios/fisiologia , Recompensa
2.
Cell ; 167(4): 1028-1040.e15, 2016 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-27881301

RESUMO

Kinetochores, multisubunit protein assemblies, connect chromosomes to spindle microtubules to promote chromosome segregation. The 10-subunit KMN assembly (comprising KNL1, MIS12, and NDC80 complexes, designated KNL1C, MIS12C, and NDC80C) binds microtubules and regulates mitotic checkpoint function through NDC80C and KNL1C, respectively. MIS12C, on the other hand, connects the KMN to the chromosome-proximal domain of the kinetochore through a direct interaction with CENP-C. The structural basis for this crucial bridging function of MIS12C is unknown. Here, we report crystal structures of human MIS12C associated with a fragment of CENP-C and unveil the role of Aurora B kinase in the regulation of this interaction. The structure of MIS12:CENP-C complements previously determined high-resolution structures of functional regions of NDC80C and KNL1C and allows us to build a near-complete structural model of the KMN assembly. Our work illuminates the structural organization of essential chromosome segregation machinery that is conserved in most eukaryotes.


Assuntos
Proteínas Cromossômicas não Histona/química , Cristalografia por Raios X , Cinetocoros/química , Complexos Multiproteicos/química , Animais , Aurora Quinase B/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Proteínas do Citoesqueleto , Humanos , Proteínas Associadas aos Microtúbulos/química , Proteínas Associadas aos Microtúbulos/metabolismo , Modelos Químicos , Complexos Multiproteicos/metabolismo , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo
3.
EMBO J ; 43(4): 637-662, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38243117

RESUMO

The E. coli transcriptome at the cell's poles (polar transcriptome) is unique compared to the membrane and cytosol. Several factors have been suggested to mediate mRNA localization to the membrane, but the mechanism underlying polar localization of mRNAs remains unknown. Here, we combined a candidate system approach with proteomics to identify factors that mediate mRNAs localization to the cell poles. We identified the pole-to-pole oscillating protein MinD as an essential factor regulating polar mRNA localization, although it is not able to bind RNA directly. We demonstrate that RNase E, previously shown to interact with MinD, is required for proper localization of polar mRNAs. Using in silico modeling followed by experimental validation, the membrane-binding site in RNase E was found to mediate binding to MinD. Intriguingly, not only does MinD affect RNase E interaction with the membrane, but it also affects its mode of action and dynamics. Polar accumulation of RNase E in ΔminCDE cells resulted in destabilization and depletion of mRNAs from poles. Finally, we show that mislocalization of polar mRNAs may prevent polar localization of their protein products. Taken together, our findings show that the interplay between MinD and RNase E determines the composition of the polar transcriptome, thus assigning previously unknown roles for both proteins.


Assuntos
Proteínas de Escherichia coli , Escherichia coli , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Endorribonucleases/genética , Endorribonucleases/metabolismo , Proteínas de Bactérias/metabolismo , Adenosina Trifosfatases/metabolismo
4.
Proc Natl Acad Sci U S A ; 121(30): e2320378121, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39008675

RESUMO

The neuroscientific examination of music processing in audio-visual contexts offers a valuable framework to assess how auditory information influences the emotional encoding of visual information. Using fMRI during naturalistic film viewing, we investigated the neural mechanisms underlying the effect of music on valence inferences during mental state attribution. Thirty-eight participants watched the same short-film accompanied by systematically controlled consonant or dissonant music. Subjects were instructed to think about the main character's intentions. The results revealed that increasing levels of dissonance led to more negatively valenced inferences, displaying the profound emotional impact of musical dissonance. Crucially, at the neuroscientific level and despite music being the sole manipulation, dissonance evoked the response of the primary visual cortex (V1). Functional/effective connectivity analysis showed a stronger coupling between the auditory ventral stream (AVS) and V1 in response to tonal dissonance and demonstrated the modulation of early visual processing via top-down feedback inputs from the AVS to V1. These V1 signal changes indicate the influence of high-level contextual representations associated with tonal dissonance on early visual cortices, serving to facilitate the emotional interpretation of visual information. Our results highlight the significance of employing systematically controlled music, which can isolate emotional valence from the arousal dimension, to elucidate the brain's sound-to-meaning interface and its distributive crossmodal effects on early visual encoding during naturalistic film viewing.


Assuntos
Percepção Auditiva , Emoções , Imageamento por Ressonância Magnética , Música , Percepção Visual , Humanos , Música/psicologia , Feminino , Masculino , Adulto , Percepção Visual/fisiologia , Percepção Auditiva/fisiologia , Emoções/fisiologia , Adulto Jovem , Mapeamento Encefálico , Estimulação Acústica , Córtex Visual/fisiologia , Córtex Visual/diagnóstico por imagem , Córtex Visual Primário/fisiologia , Estimulação Luminosa/métodos
5.
Proc Natl Acad Sci U S A ; 120(49): e2303162120, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37983484

RESUMO

Many actions have instrumental aims, in which we move our bodies to achieve a physical outcome in the environment. However, we also perform actions with epistemic aims, in which we move our bodies to acquire information and learn about the world. A large literature on action recognition investigates how observers represent and understand the former class of actions; but what about the latter class? Can one person tell, just by observing another person's movements, what they are trying to learn? Here, five experiments explore epistemic action understanding. We filmed volunteers playing a "physics game" consisting of two rounds: Players shook an opaque box and attempted to determine i) the number of objects hidden inside, or ii) the shape of the objects inside. Then, independent subjects watched these videos and were asked to determine which videos came from which round: Who was shaking for number and who was shaking for shape? Across several variations, observers successfully determined what an actor was trying to learn, based only on their actions (i.e., how they shook the box)-even when the box's contents were identical across rounds. These results demonstrate that humans can infer epistemic intent from physical behaviors, adding a new dimension to research on action understanding.


Assuntos
Aprendizagem , Movimento , Humanos , Reconhecimento Psicológico , Intenção
6.
Proc Natl Acad Sci U S A ; 120(1): e2022385119, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36584298

RESUMO

The "Reading the Mind in the Eyes" Test (Eyes Test) is a widely used assessment of "theory of mind." The NIMH Research Domain Criteria recommends it as one of two tests for "understanding mental states." Previous studies have demonstrated an on-average female advantage on the Eyes Test. However, it is unknown whether this female advantage exists across the lifespan and across a large number of countries. Thus, we tested sex and age differences using the English version of the Eyes Test in adolescents and adults across 57 countries. We also tested for associations with sociodemographic and cognitive/personality factors. We leveraged one discovery dataset (N = 305,726) and three validation datasets (Ns = 642; 5,284; and 1,087). The results show that: i) there is a replicable on-average female advantage in performance on the Eyes Test; ii) performance increases through adolescence and shallowly declines across adulthood; iii) the on-average female advantage is evident across the lifespan; iv) there is a significant on-average female advantage in 36 out of 57 countries; v) there is a significant on-average female advantage on translated (non-English) versions of the Eyes Test in 12 out of 16 countries, as confirmed by a systematic review; vi) D-scores, or empathizing-systemizing, predict Eyes Test performance above and beyond sex differences; and vii) the female advantage is negatively linked to "prosperity" and "autonomy," and positively linked to "collectivism," as confirmed by exploratory country-level analyses. We conclude that the on-average female advantage on the Eyes Test is observed across ages and most countries.


Assuntos
Olho , Caracteres Sexuais , Adulto , Adolescente , Humanos , Masculino , Feminino , Empatia
7.
Mol Psychiatry ; 29(4): 1114-1127, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38177353

RESUMO

The discovery that subanesthetic doses of (R, S)-ketamine (ketamine) and (S)-ketamine (esketamine) rapidly induce antidepressant effects and promote sustained actions following drug clearance in depressed patients who are treatment-resistant to other therapies has resulted in a paradigm shift in the conceptualization of how rapidly and effectively depression can be treated. Consequently, the mechanism(s) that next generation antidepressants may engage to improve pathophysiology and resultant symptomology are being reconceptualized. Impaired excitatory glutamatergic synapses in mood-regulating circuits are likely a substantial contributor to the pathophysiology of depression. Metaplasticity is the process of regulating future capacity for plasticity by priming neurons with a stimulation that alters later neuronal plasticity responses. Accordingly, the development of treatment modalities that specifically modulate the duration, direction, or magnitude of glutamatergic synaptic plasticity events such as long-term potentiation (LTP), defined here as metaplastogens, may be an effective approach to reverse the pathophysiology underlying depression and improve depression symptoms. We review evidence that the initiating mechanisms of pharmacologically diverse rapid-acting antidepressants (i.e., ketamine mimetics) converge on consistent downstream molecular mediators that facilitate the expression/maintenance of increased synaptic strength and resultant persisting antidepressant effects. Specifically, while the initiating mechanisms of these therapies may differ (e.g., cell type-specificity, N-methyl-D-aspartate receptor (NMDAR) subtype-selective inhibition vs activation, metabotropic glutamate receptor 2/3 antagonism, AMPA receptor potentiation, 5-HT receptor-activating psychedelics, etc.), the sustained therapeutic mechanisms of putative rapid-acting antidepressants will be mediated, in part, by metaplastic effects that converge on consistent molecular mediators to enhance excitatory neurotransmission and altered capacity for synaptic plasticity. We conclude that the convergence of these therapeutic mechanisms provides the opportunity for metaplasticity processes to be harnessed as a druggable plasticity mechanism by next-generation therapeutics. Further, targeting metaplastic mechanisms presents therapeutic advantages including decreased dosing frequency and associated diminished adverse responses by eliminating the requirement for the drug to be continuously present.


Assuntos
Antidepressivos , Ketamina , Plasticidade Neuronal , Humanos , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Plasticidade Neuronal/efeitos dos fármacos , Ketamina/farmacologia , Ketamina/uso terapêutico , Animais , Depressão/tratamento farmacológico , Potenciação de Longa Duração/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/metabolismo , Sinapses/efeitos dos fármacos , Sinapses/metabolismo
8.
Brain ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38889248

RESUMO

The default mode network (DMN) is a widely distributed, intrinsic brain network thought to play a crucial role in internally-directed cognition. The present study employs stereo-electroencephalography in 13 human patients, obtaining high resolution neural recordings across multiple canonical DMN regions during two processes that have been associated with creative thinking: spontaneous and divergent thought. We probe these two DMN-associated higher cognitive functions through mind wandering and alternate uses tasks, respectively. Our results reveal DMN recruitment during both tasks, as well as a task-specific dissociation in spatiotemporal response dynamics. When compared to the fronto-parietal network, DMN activity was characterized by a stronger increase in gamma band power (30-70 Hz) coupled with lower theta band power (4-8 Hz). The difference in activity between the two networks was especially strong during the mind wandering task. Within the DMN, we found that the tasks showed different dynamics, with the alternate uses task engaging the DMN more during the initial stage of the task, and mind wandering in the later stage. Gamma power changes were mainly driven by lateral DMN sites, while theta power displayed task-specific effects. During alternate uses task, theta changes did not show spatial differences within the DMN, while mind wandering was associated to an early lateral and late dorsomedial DMN engagement. Furthermore, causal manipulations of DMN regions using direct cortical stimulation preferentially decreased the originality of responses in the alternative uses task, without affecting fluency or mind wandering. Our results suggest that DMN activity is flexibly modulated as a function of specific cognitive processes and supports its causal role in divergent thinking. These findings shed light on the neural constructs supporting different forms of cognition and provide causal evidence for the role of DMN in the generation of original connections among concepts.

9.
Cereb Cortex ; 34(2)2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38300213

RESUMO

Humans continuously alternate between online attention to the current environment and offline attention to internally generated thought and imagery. This may be a fundamental feature of the waking brain, but remains poorly understood. Here, we took a data-driven approach to defining online and offline states of wakefulness, using machine learning methods applied to measures of sensory responsiveness, subjective report, electroencephalogram (EEG), and pupil diameter. We tested the effect of cognitive load on the structure and prevalence of online and offline states, hypothesizing that time spent offline would increase as cognitive load of an ongoing task decreased. We also expected that alternation between online and offline states would persist even in the absence of a cognitive task. As in prior studies, we arrived at a three-state model comprised of one online state and two offline states. As predicted, when cognitive load was high, more time was spent online. Also as predicted, the same three states were present even when participants were not performing a task. These observations confirm our method is successful at isolating seconds-long periods of offline time. Varying cognitive load may be a useful way to manipulate time spent in at least one of these offline states in future experimental studies.


Assuntos
Encéfalo , Vigília , Humanos , Pensamento , Eletroencefalografia , Cognição
10.
Cereb Cortex ; 34(2)2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38342686

RESUMO

Communication, especially conversation, is essential for human social life. Many previous studies have examined the neuroscientific underpinnings of conversation, i.e. language comprehension and speech production. However, conversation inherently involves two or more people, and unless two people actually interact with one another, the nature of the conversation cannot be truly revealed. Therefore, in this study, we used two magnetoencephalographs that were connected together, and simultaneously recorded brain activity while two people took turns speaking in a word association/alphabet completion task. We compared the amplitude modulation of the alpha- and beta-band rhythms within each of the 62 brain regions under semantic (word association; less predictable) and non-semantic (alphabet completion; more predictable) conditions. We found that the amplitudes of the rhythms were significantly different between conditions in a wide range of brain regions. Additionally, significant differences were observed in nearly the same group of brain regions after versus before each utterance, indicating that a wide range of brain areas is involved in predicting a conversation partner's next utterance. This result supports the idea that mentalizing, e.g. predicting another person's speech, plays an important role in conversation, and suggests that the neural network implicated in mentalizing extends over a wide range of brain regions.


Assuntos
Percepção da Fala , Fala , Humanos , Semântica , Comunicação , Encéfalo , Magnetoencefalografia
11.
Proc Natl Acad Sci U S A ; 119(49): e2211628119, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36449541

RESUMO

People are intuitive Dualists-they tacitly consider the mind as ethereal, distinct from the body. Here we ask whether Dualism emerges naturally from the conflicting core principles that guide reasoning about objects, on the one hand, and about the minds of agents (theory of mind, ToM), on the other. To address this question, we explore Dualist reasoning in autism spectrum disorder (ASD)-a congenital disorder known to compromise ToM. If Dualism arises from ToM, then ASD ought to attenuate Dualism and promote Physicalism. In line with this prediction, Experiment 1 shows that, compared to controls, people with ASD are more likely to view psychological traits as embodied-as likely to manifest in a replica of one's body. Experiment 2 demonstrates that, unlike controls, people with ASD do not consider thoughts as disembodied-as persistent in the afterlife (upon the body's demise). If ASD promotes the perception of the psyche as embodied, and if (per Essentialism) embodiment suggests innateness, then ASD should further promote Nativism-this bias is shown in Experiment 3. Finally, Experiment 4 demonstrates that, in neurotypical (NT) participants, difficulties with ToM correlate with Physicalism. These results are the first to show that ASD attenuates Dualist reasoning and to link Dualism to ToM. These conclusions suggest that the mind-body distinction might be natural for people to entertain.


Assuntos
Anestésicos Gerais , Transtorno do Espectro Autista , Transtorno Autístico , Humanos , Resolução de Problemas , Percepção
12.
Proc Natl Acad Sci U S A ; 119(32): e2105642119, 2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-35930665

RESUMO

We care about what others think of us and often try to present ourselves in a good light. What cognitive capacities underlie our ability to think (or even worry) about reputation, and how do these concerns manifest as strategic self-presentational behaviors? Even though the tendency to modify one's behaviors in the presence of others emerges early in life, the degree to which these behaviors reflect a rich understanding of what others think about the self has remained an open question. Bridging prior work on reputation management, communication, and theory of mind development in early childhood, here we investigate young children's ability to infer and revise others' mental representation of the self. Across four experiments, we find that 3- and 4-y-old children's decisions about to whom to communicate (Experiment 1), what to communicate (Experiments 2 and 3), and which joint activity to engage in with a partner (Experiment 4) are systematically influenced by the partner's observations of the children's own past performance. Children in these studies chose to present self-relevant information selectively and strategically when it could revise the partner's outdated, negative representation of the self. Extending research on children's ability to engage in informative communication, these results demonstrate the sophistication of early self-presentational behaviors: Even young children can draw rich inferences about what others think of them and communicate self-relevant information to revise these representations.


Assuntos
Comunicação , Psicologia da Criança , Teoria da Mente , Criança , Pré-Escolar , Humanos
13.
Proc Natl Acad Sci U S A ; 119(18): e2116933119, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35486693

RESUMO

This article argues that consciousness has a logically sound, explanatory framework, different from typical accounts that suffer from hidden mysticism. The article has three main parts. The first describes background principles concerning information processing in the brain, from which one can deduce a general, rational framework for explaining consciousness. The second part describes a specific theory that embodies those background principles, the Attention Schema Theory. In the past several years, a growing body of experimental evidence-behavioral evidence, brain imaging evidence, and computational modeling-has addressed aspects of the theory. The final part discusses the evolution of consciousness. By emphasizing the specific role of consciousness in cognition and behavior, the present approach leads to a proposed account of how consciousness may have evolved over millions of years, from fish to humans. The goal of this article is to present a comprehensive, overarching framework in which we can understand scientifically what consciousness is and what key adaptive roles it plays in brain function.


Assuntos
Cognição , Estado de Consciência , Animais , Atenção , Encéfalo , Simulação por Computador
14.
Proc Natl Acad Sci U S A ; 119(41): e2200511119, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36194631

RESUMO

Mind blanking (MB) is a waking state during which we do not report any mental content. The phenomenology of MB challenges the view of a constantly thinking mind. Here, we comprehensively characterize the MB's neurobehavioral profile with the aim to delineate its role during ongoing mentation. Using functional MRI experience sampling, we show that the reportability of MB is less frequent, faster, and with lower transitional dynamics than other mental states, pointing to its role as a transient mental relay. Regarding its neural underpinnings, we observed higher global signal amplitude during MB reports, indicating a distinct physiological state. Using the time-varying functional connectome, we show that MB reports can be classified with high accuracy, suggesting that MB has a unique neural composition. Indeed, a pattern of global positive-phase coherence shows the highest similarity to the connectivity patterns associated with MB reports. We interpret this pattern's rigid signal architecture as hindering content reportability due to the brain's inability to differentiate signals in an informative way. Collectively, we show that MB has a unique neurobehavioral profile, indicating that nonreportable mental events can happen during wakefulness. Our results add to the characterization of spontaneous mentation and pave the way for more mechanistic investigations of MB's phenomenology.


Assuntos
Mapeamento Encefálico , Conectoma , Pensamento , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética
15.
J Neurosci ; 43(40): 6807-6815, 2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37643862

RESUMO

Mind-blanking (MB) is termed as the inability to report our immediate-past mental content. In contrast to mental states with reportable content, such as mind-wandering or sensory perceptions, the neural correlates of MB started getting elucidated only recently. A notable particularity that pertains to MB studies is the way MB is instructed for reporting, like by deliberately asking participants to "empty their minds." Such instructions were shown to induce fMRI activations in frontal brain regions, typically associated with metacognition and self-evaluative processes, suggesting that MB may be a result of intentional mental content suppression. Here, we aim at examining this hypothesis by determining the neural correlates of MB without induction. Using fMRI combined with experience-sampling in 31 participants (22 female), univariate analysis of MB reports revealed deactivations in occipital, frontal, parietal, and thalamic areas, but no activations in prefrontal regions. These findings were confirmed using Bayesian region-of-interest analysis on areas previously shown to be implicated in induced MB, where we report evidence for frontal deactivations during MB reports compared with other mental states. Contrast analysis between reports of MB and content-oriented mental states also revealed deactivations in the left angular gyrus. We propose that these effects characterize a neuronal profile of MB, where key thalamocortical nodes are unable to communicate and formulate reportable content. Collectively, we show that study instructions for MB lead to differential neural activation. These results provide mechanistic insights linked to the phenomenology of MB and point to the possibility of MB being expressed in different forms.SIGNIFICANCE STATEMENT This study explores how brain activity changes when individuals report unidentifiable thoughts, a phenomenon known as mind-blanking (MB). It aims to detect changes in brain activations and deactivations when MB is reported spontaneously, as opposed to the neural responses that have been previously reported when MB is induced. By means of brain imaging and experience-sampling, the study points to reduced brain activity in a wide number of regions, including those mesio-frontally which were previously detected as activated during induced MB. These results enhance our understanding of the complexity of spontaneous thinking and contribute to broader discussions on consciousness and reportable experience.


Assuntos
Mapeamento Encefálico , Encéfalo , Humanos , Feminino , Teorema de Bayes , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Estado de Consciência/fisiologia , Lobo Parietal/fisiologia , Imageamento por Ressonância Magnética
16.
Neuroimage ; 294: 120638, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38719153

RESUMO

It has been found that mind wandering can impair motor control. However, it remains unclear whether the impact of mind wandering on motor control is modulated by movement difficulty and its associated neural mechanisms. To address this issue, we manipulated movement difficulty using handedness and finger dexterity separately in two signal-response tasks with identical experiment designs, in which right-handed participants performed key-pressing and key-releasing movements with the specified fingers, and they had to intermittently report whether their attention was "On task" or "Off task." Key-releasing with the right index finger (RI) had a faster reaction time and stronger contralateral delta-theta (1-7 Hz) functional connectivity than with the left index (LI) in Experiment 1, and mind wandering only reduced the contralateral delta-theta functional connectivity and midfrontal delta-theta activity for key-releasing with RI. Key-pressing with right index and middle fingers (RIR) had a faster reaction time and stronger midfrontal delta-theta activity than with right index and ring fingers (RIR) in Experiment 2, and mind wandering only reduced the midfrontal delta-theta activity for key-pressing with RIM. Theta oscillations are vital in motor control. These findings suggest that mind wandering only impairs the motor control of relatively simple movements without affecting the difficult ones. It supports the notion that mind wandering competes for executive resources with the primary task. Moreover, the quantity of executive resources recruited for a task and how these resources are allocated is contingent upon the task difficulty, which may determine whether mind wandering would interfere with motor control.


Assuntos
Atenção , Desempenho Psicomotor , Tempo de Reação , Humanos , Masculino , Feminino , Adulto Jovem , Atenção/fisiologia , Adulto , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Movimento/fisiologia , Lateralidade Funcional/fisiologia , Dedos/fisiologia , Imageamento por Ressonância Magnética , Encéfalo/fisiologia
17.
J Neurophysiol ; 132(2): 375-388, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38958281

RESUMO

The default network is widely implicated as a common neural substrate for self-generated thought, such as remembering one's past (autobiographical memory) and imagining the thoughts and feelings of others (theory of mind). Findings that the default network comprises subnetworks of regions, some commonly and some distinctly involved across processes, suggest that one's own experiences inform their understanding of others. With the advent of precision functional MRI (fMRI) methods, however, it is unclear if this shared substrate is observed instead due to traditional group analysis methods. We investigated this possibility using a novel combination of methodological strategies. Twenty-three participants underwent multi-echo resting-state and task fMRI. We used their resting-state scans to conduct cortical parcellation sensitive to individual variation while preserving our ability to conduct group analysis. Using multivariate analyses, we assessed the functional activation and connectivity profiles of default network regions while participants engaged in autobiographical memory, theory of mind, or a sensorimotor control condition. Across the default network, we observed stronger activity associated with both autobiographical memory and theory of mind compared to the control condition. Nonetheless, we also observed that some regions showed preferential activity to either experimental condition, in line with past work. The connectivity results similarly indicated shared and distinct functional profiles. Our results support that autobiographical memory and theory of mind, two theoretically important and widely studied domains of social cognition, evoke common and distinct aspects of the default network even when ensuring high fidelity to individual-specific characteristics.NEW & NOTEWORTHY We used cutting-edge precision functional MRI (fMRI) methods such as multi-echo fMRI acquisition and denoising, a robust experimental paradigm, and individualized cortical parcellation across 23 participants to provide evidence that remembering one's past experiences and imagining the thoughts and feelings of others share a common neural substrate. Evidence from activation and connectivity analyses indicate overlapping and distinct functional profiles of these widely studied episodic and social processes.


Assuntos
Rede de Modo Padrão , Imageamento por Ressonância Magnética , Memória Episódica , Teoria da Mente , Humanos , Masculino , Feminino , Adulto , Teoria da Mente/fisiologia , Rede de Modo Padrão/fisiologia , Rede de Modo Padrão/diagnóstico por imagem , Adulto Jovem , Mapeamento Encefálico , Conectoma
18.
Cancer ; 130(14): 2552-2560, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38943468

RESUMO

BACKGROUND: Hospitalized patients with cancer often experience acute and/or chronic pain. Although virtual reality (VR) has been extensively studied across a wide range of clinical settings, no studies have yet evaluated potential impact on pain management in this patient population. METHODS: Prospective randomized controlled trial at an urban academic hospital comparing VR against an active control to mitigate moderate-severe cancer disease and treatment-related pain. RESULTS: A total of 128 adult hospitalized patients with cancer (any tumor type) were randomized to 10 minutes of immersive VR distraction therapy or 10 minutes of two-dimensional guided imagery distraction therapy delivered by handheld tablet. Participants in the two arms were similar in age, sex, race, presence of metastatic disease, concurrent pain specialist consultation, and baseline opioid use. Although both groups experienced improved self-reported pain scores (primary outcome), those randomized to VR experienced significantly greater reduction in pain immediately after intervention compared with active control (p = .03). This difference was sustained for 24 hours as well (p = .004). Within-group analysis showed significant improvement in VR arm of pain bothersomeness (p = .05) and general distress (p = .03) as well. CONCLUSION: Among hospitalized adult patients with moderate-severe pain related to cancer and cancer therapies, VR provided more nonpharmacologic pain relief than active control and this benefit sustained long after conclusion of the intervention. PLAIN LANGUAGE SUMMARY: Virtual reality (VR), a developing technology that immerses the user in new environments, has been shown to improve pain in different patient populations. To test the role of VR in improving pain in hospitalized patients with cancer who report moderate-severe pain, we compared the impact of a 10-minute immersive VR intervention to that of a 10-minute two-dimensional guided imagery experience to improve self-reported pain scores. We found that, although both interventions improved pain, VR did so significantly more. Moreover, participants assigned to VR had sustained improvement in pain 24 hours later.


Assuntos
Dor do Câncer , Neoplasias , Manejo da Dor , Realidade Virtual , Humanos , Masculino , Feminino , Manejo da Dor/métodos , Pessoa de Meia-Idade , Neoplasias/complicações , Neoplasias/terapia , Neoplasias/psicologia , Idoso , Dor do Câncer/terapia , Dor do Câncer/psicologia , Estudos Prospectivos , Adulto , Hospitalização , Medição da Dor , Terapia de Exposição à Realidade Virtual/métodos
19.
Eur J Neurosci ; 59(5): 786-795, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37778749

RESUMO

Mind blanking is a mental state in which attention does not bring any perceptual input into conscious awareness. As this state is still largely unexplored, we suggest that a comprehensive understanding of mind blanking can be achieved through a multifaceted approach combining self-assessment methods, neuroimaging and neuromodulation. In this article, we explain how electroencephalography and transcranial magnetic stimulation could be combined to help determine whether mind blanking is associated with a lack of mental content or a lack of linguistically or conceptually determinable mental content. We also question whether mind blanking occurs spontaneously or intentionally and whether these two forms are instantiated by the same or different neural correlates.


Assuntos
Atenção , Estado de Consciência , Atenção/fisiologia , Estado de Consciência/fisiologia , Estimulação Magnética Transcraniana , Neuroimagem
20.
Eur J Neurosci ; 59(6): 1213-1226, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37670685

RESUMO

In Parkinson's disease (PD), impairment of Theory of Mind (ToM) has recently attracted an increasing number of neuroscientific investigations. If and how functional connectivity of the ToM network is altered in PD is still an open question. First, we explored whether ToM network connectivity shows potential PD-specific functional alterations when compared to healthy controls (HC). Second, we tested the role of the duration of PD in the evolution of functional alterations in the ToM network. Between-group connectivity alterations were computed adopting resting-state functional magnetic resonance imaging (rs-fMRI) data of four groups: PD patients with short disease duration (PD-1, n = 72); PD patients with long disease duration (PD-2, n = 22); healthy controls for PD-1 (HC-1, n = 69); healthy controls for PD-2 (HC-2, n = 22). We explored connectivity differences in the ToM network within and between its three subnetworks: Affective, Cognitive and Core. PD-1 presented a global pattern of decreased functional connectivity within the ToM network, compared to HC-1. The alterations mainly involved the Cognitive and Affective ToM subnetworks and their reciprocal connections. PD-2-those with longer disease duration-showed an increased connectivity spanning the entire ToM network, albeit less consistently in the Core ToM network, compared to both the PD-1 and the HC-2 groups. Functional connectivity within the ToM network is altered in PD. The alterations follow a graded pattern, with decreased connectivity at short disease duration, which broadens to a generalized increase with longer disease duration. The alterations involve both the Cognitive and Affective subnetworks of ToM.


Assuntos
Doença de Parkinson , Teoria da Mente , Humanos , Receptor de Morte Celular Programada 1 , Imageamento por Ressonância Magnética
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