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1.
Cell ; 183(3): 605-619.e22, 2020 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-33031743

RESUMO

Exploration of novel environments ensures survival and evolutionary fitness. It is expressed through exploratory bouts and arrests that change dynamically based on experience. Neural circuits mediating exploratory behavior should therefore integrate experience and use it to select the proper behavioral output. Using a spatial exploration assay, we uncovered an experience-dependent increase in momentary arrests in locations where animals arrested previously. Calcium imaging in freely exploring mice revealed a genetically and projection-defined neuronal ensemble in the basolateral amygdala that is active during self-paced behavioral arrests. This ensemble was recruited in an experience-dependent manner, and closed-loop optogenetic manipulation of these neurons revealed that they are sufficient and necessary to drive experience-dependent arrests during exploration. Projection-specific imaging and optogenetic experiments revealed that these arrests are effected by basolateral amygdala neurons projecting to the central amygdala, uncovering an amygdala circuit that mediates momentary arrests in familiar places but not avoidance or anxiety/fear-like behaviors.


Assuntos
Complexo Nuclear Basolateral da Amígdala/fisiologia , Núcleo Central da Amígdala/fisiologia , Comportamento Exploratório/fisiologia , Rede Nervosa/fisiologia , Animais , Complexo Nuclear Basolateral da Amígdala/diagnóstico por imagem , Comportamento Animal/fisiologia , Núcleo Central da Amígdala/diagnóstico por imagem , Feminino , Locomoção , Aprendizado de Máquina , Masculino , Camundongos Endogâmicos C57BL , Neurônios/fisiologia , Imagem Óptica
2.
Annu Rev Neurosci ; 47(1): 21-40, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38360565

RESUMO

It is a common view that the intricate array of specialized domains in the ventral visual pathway is innately prespecified. What this review postulates is that it is not. We explore the origins of domain specificity, hypothesizing that the adult brain emerges from an interplay between a domain-general map-based architecture, shaped by intrinsic mechanisms, and experience. We argue that the most fundamental innate organization of cortex in general, and not just the visual pathway, is a map-based topography that governs how the environment maps onto the brain, how brain areas interconnect, and ultimately, how the brain processes information.


Assuntos
Encéfalo , Humanos , Encéfalo/fisiologia , Animais , Vias Visuais/fisiologia , Mapeamento Encefálico/métodos
3.
Annu Rev Neurosci ; 45: 1-21, 2022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-34936810

RESUMO

When navigating through space, we must maintain a representation of our position in real time; when recalling a past episode, a memory can come back in a flash. Interestingly, the brain's spatial representation system, including the hippocampus, supports these two distinct timescale functions. How are neural representations of space used in the service of both real-world navigation and internal mnemonic processes? Recent progress has identified sequences of hippocampal place cells, evolving at multiple timescales in accordance with either navigational behaviors or internal oscillations, that underlie these functions. We review experimental findings on experience-dependent modulation of these sequential representations and consider how they link real-world navigation to time-compressed memories. We further discuss recent work suggesting the prevalence of these sequences beyond hippocampus and propose that these multiple-timescale mechanisms may represent a general algorithm for organizing cell assemblies, potentially unifying the dual roles of the spatial representation system in memory and navigation.


Assuntos
Hipocampo , Memória , Percepção Espacial
4.
Annu Rev Neurosci ; 45: 471-489, 2022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35803589

RESUMO

Unimodal sensory loss leads to structural and functional changes in both deprived and nondeprived brain circuits. This process is broadly known as cross-modal plasticity. The evidence available indicates that cross-modal changes underlie the enhanced performances of the spared sensory modalities in deprived subjects. Sensory experience is a fundamental driver of cross-modal plasticity, yet there is evidence from early-visually deprived models supporting an additional role for experience-independent factors. These experience-independent factors are expected to act early in development and constrain neuronal plasticity at later stages. Here we review the cross-modal adaptations elicited by congenital or induced visual deprivation prior to vision. In most of these studies, cross-modal adaptations have been addressed at the structural and functional levels. Here, we also appraise recent data regarding behavioral performance in early-visually deprived models. However, further research is needed to explore how circuit reorganization affects their function and what brings about enhanced behavioral performance.


Assuntos
Plasticidade Neuronal , Privação Sensorial , Encéfalo , Humanos , Plasticidade Neuronal/fisiologia , Privação Sensorial/fisiologia , Visão Ocular
5.
Trends Genet ; 40(6): 480-494, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38658255

RESUMO

Embryonic neurodevelopment, particularly neural progenitor differentiation into post-mitotic neurons, has been extensively studied. While the number and composition of post-mitotic neurons remain relatively constant from birth to adulthood, the brain undergoes significant postnatal maturation marked by major property changes frequently disrupted in neural diseases. This review first summarizes recent characterizations of the functional and molecular maturation of the postnatal nervous system. We then review regulatory mechanisms controlling the precise gene expression changes crucial for the intricate sequence of maturation events, highlighting experience-dependent versus cell-intrinsic genetic timer mechanisms. Despite significant advances in understanding of the gene-environmental regulation of postnatal neuronal maturation, many aspects remain unknown. The review concludes with our perspective on exciting future research directions in the next decade.


Assuntos
Interação Gene-Ambiente , Neurogênese , Neurônios , Humanos , Neurônios/citologia , Neurônios/metabolismo , Animais , Neurogênese/genética , Diferenciação Celular/genética , Mitose/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Encéfalo/citologia , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/citologia
6.
Proc Natl Acad Sci U S A ; 121(12): e2317751121, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38489382

RESUMO

Do people's attitudes toward the (a)symmetry of an outcome distribution affect their choices? Financial investors seek return distributions with frequent small returns but few large ones, consistent with leading models of choice in economics and finance that assume right-skewed preferences. In contrast, many experiments in which decision-makers learn about choice options through experience find the opposite choice tendency, in favor of left-skewed options. To reconcile these seemingly contradicting findings, the present work investigates the effect of skewness on choices in experience-based decisions. Across seven studies, we show that apparent preferences for left-skewed outcome distributions are a consequence of those distributions having a higher value in most direct outcome comparisons, a "frequent-winner effect." By manipulating which option is the frequent winner, we show that choice tendencies for frequent winners can be obtained even with identical outcome distributions. Moreover, systematic choice tendencies in favor of right- or left-skewed options can be obtained by manipulating which option is experienced as the frequent winner. We also find evidence for an intrinsic preference for right-skewed outcome distributions. The frequent-winner phenomenon is robust to variations in outcome distributions and experimental paradigms. These findings are confirmed by computational analyses in which a reinforcement-learning model capturing frequent winning and intrinsic skewness preferences provides the best account of the data. Our work reconciles conflicting findings of aggregated behavior in financial markets and experiments and highlights the need for theories of decision-making sensitive to joint outcome distributions of the available options.


Assuntos
Comportamento de Escolha , Tomada de Decisões , Humanos , Aprendizagem , Reforço Psicológico
7.
Proc Natl Acad Sci U S A ; 121(19): e2318128121, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38687795

RESUMO

Childhood maltreatment has been linked to adult somatic symptoms, although this has rarely been examined in daily life. Furthermore, the localization of somatization associated with childhood maltreatment and its subtypes is unknown. This large-scale experience sampling study used body maps to examine the relationships between childhood maltreatment, its subtypes, and the intensity and location of negative somatic sensations in daily life. Participants (N = 2,234; 33% female and 67% male) were part of MyBPLab 2.0, a study conducted using a bespoke mobile phone application. Four categories of childhood maltreatment (emotional abuse, emotional neglect, physical abuse, and physical neglect) were measured using the Childhood Trauma Questionnaire. Using gender-matched human silhouettes, participants indicated the location and intensity of feelings of negative activation in the body. Childhood maltreatment generally and its four measured subtypes were all positively associated with heightened negative activation on both the front and back body maps. For females, total childhood maltreatment was associated with negative activation in the abdomen and lower back, while for males, the association was localized to the lower back. Similarly, each of the four subscales had localized associations with negative activation in the abdomen and lower back in females and lower back in males, except for emotional abuse, which was also associated with negative activation in the abdomen in males. These associations likely reflect increased somatization in individuals exposed to childhood maltreatment, suggesting a role for psychotherapeutic interventions in alleviating associated distress.


Assuntos
Sintomas Inexplicáveis , Humanos , Feminino , Masculino , Adulto , Transtornos Somatoformes/psicologia , Transtornos Somatoformes/etiologia , Maus-Tratos Infantis/psicologia , Inquéritos e Questionários , Criança , Pessoa de Meia-Idade , Sobreviventes Adultos de Maus-Tratos Infantis/psicologia , Adulto Jovem
8.
Proc Natl Acad Sci U S A ; 120(30): e2219340120, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37459544

RESUMO

Coordinated functioning of the two cortical hemispheres is crucial for perception. The human auditory cortex (ACx) shows functional lateralization with the left hemisphere specialized for processing speech, whereas the right analyzes spectral content. In mice, virgin females demonstrate a left-hemisphere response bias to pup vocalizations that strengthens with motherhood. However, how this lateralized function is established is unclear. We developed a widefield imaging microscope to simultaneously image both hemispheres of mice to bilaterally monitor functional responses. We found that global ACx topography is symmetrical and stereotyped. In both male and virgin female mice, the secondary auditory cortex (A2) in the left hemisphere shows larger responses than right to high-frequency tones and adult vocalizations; however, only virgin female mice show a left-hemisphere bias in A2 in response to adult pain calls. These results indicate hemispheric bias with both sex-independent and -dependent aspects. Analyzing cross-hemispheric functional correlations showed that asymmetries exist in the strength of correlations between DM-AAF and A2-AAF, while other ACx areas showed smaller differences. We found that A2 showed lower cross-hemisphere correlation than other cortical areas, consistent with the lateralized functional activation of A2. Cross-hemispheric activity correlations are lower in deaf, otoferlin knockout (OTOF-/-) mice, indicating that the development of functional cross-hemispheric connections is experience dependent. Together, our results reveal that ACx is topographically symmetric at the macroscopic scale but that higher-order A2 shows sex-dependent and independent lateralized responses due to asymmetric intercortical functional connections. Moreover, our results suggest that sensory experience is required to establish functional cross-hemispheric connectivity.


Assuntos
Córtex Auditivo , Adulto , Masculino , Humanos , Feminino , Animais , Camundongos , Córtex Auditivo/fisiologia , Cálcio , Lateralidade Funcional/fisiologia , Mapeamento Encefálico , Microscopia , Percepção Auditiva/fisiologia , Proteínas de Membrana
9.
Proc Natl Acad Sci U S A ; 120(10): e2208661120, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36857342

RESUMO

Do larger incomes make people happier? Two authors of the present paper have published contradictory answers. Using dichotomous questions about the preceding day, [Kahneman and Deaton, Proc. Natl. Acad. Sci. U.S.A. 107, 16489-16493 (2010)] reported a flattening pattern: happiness increased steadily with log(income) up to a threshold and then plateaued. Using experience sampling with a continuous scale, [Killingsworth, Proc. Natl. Acad. Sci. U.S.A. 118, e2016976118 (2021)] reported a linear-log pattern in which average happiness rose consistently with log(income). We engaged in an adversarial collaboration to search for a coherent interpretation of both studies. A reanalysis of Killingsworth's experienced sampling data confirmed the flattening pattern only for the least happy people. Happiness increases steadily with log(income) among happier people, and even accelerates in the happiest group. Complementary nonlinearities contribute to the overall linear-log relationship. We then explain why Kahneman and Deaton overstated the flattening pattern and why Killingsworth failed to find it. We suggest that Kahneman and Deaton might have reached the correct conclusion if they had described their results in terms of unhappiness rather than happiness; their measures could not discriminate among degrees of happiness because of a ceiling effect. The authors of both studies failed to anticipate that increased income is associated with systematic changes in the shape of the happiness distribution. The mislabeling of the dependent variable and the incorrect assumption of homogeneity were consequences of practices that are standard in social science but should be questioned more often. We flag the benefits of adversarial collaboration.


Assuntos
Emoções , Deficiência Múltipla de Acil Coenzima A Desidrogenase , Humanos , Felicidade , Tristeza , Apoptose , Análise por Conglomerados
10.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-37991321

RESUMO

Uncovering the neural mechanisms of ostracism experience (including its subclasses of excluded and ignored experiences) is important. However, the resting-state functional brain substrates responsible for individual differences in ostracism experience and its negative effects remain largely undefined. This study explored these issues in a sample of 198 Chinese college students by assessing the amplitude of low-frequency fluctuations and functional connectivity. The findings indicated a positive correlation between ignored experience and the amplitude of low-frequency fluctuations in the right superior frontal gyrus and the functional connectivity between the right superior frontal gyrus and left cerebellum posterior lobe. Additionally, a negative correlation was found between ignored experience and the functional connectivity between the right superior frontal gyrus and the bilateral insula as well as the bilateral inferior parietal lobule. Moreover, the mediation analysis demonstrated that the effects of the functional connectivities of right superior frontal gyrus-left cerebellum posterior lobe and right superior frontal gyrus-right inferior parietal lobule on revenge intention were mediated by ignored experience. Our study offers novel insights into the neural correlates of both individual variations in ignored experience and its typical deleterious effect. These results could deepen our understanding of individual differences in negative experiences and inspire the development of targeted interventions for social stress from the perspective of the brain.


Assuntos
Individualidade , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Lobo Parietal/diagnóstico por imagem
11.
Cereb Cortex ; 34(5)2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38798004

RESUMO

Pain experience increases individuals' perception and contagion of others' pain, but whether pain experience affects individuals' affiliative or antagonistic responses to others' pain is largely unknown. Additionally, the neural mechanisms underlying how pain experience modulates individuals' responses to others' pain remain unclear. In this study, we explored the effects of pain experience on individuals' responses to others' pain and the underlying neural mechanisms. By comparing locomotion, social, exploration, stereotyped, and anxiety-like behaviors of mice without any pain experience (naïve observers) and mice with a similar pain experience (experienced observers) when they observed the pain-free demonstrator with intraperitoneal injection of normal saline and the painful demonstrator with intraperitoneal injection of acetic acid, we found that pain experience of the observers led to decreased social avoidance to the painful demonstrator. Through whole-brain c-Fos quantification, we discovered that pain experience altered neuronal activity and enhanced functional connectivity in the mouse brain. The analysis of complex network and graph theory exhibited that functional connectivity networks and activated hub regions were altered by pain experience. Together, these findings reveal that neuronal activity and functional connectivity networks are involved in the modulation of individuals' responses to others' pain by pain experience.


Assuntos
Encéfalo , Camundongos Endogâmicos C57BL , Dor , Proteínas Proto-Oncogênicas c-fos , Animais , Camundongos , Proteínas Proto-Oncogênicas c-fos/metabolismo , Masculino , Dor/psicologia , Dor/fisiopatologia , Comportamento Social , Aprendizagem da Esquiva/fisiologia , Vias Neurais/fisiopatologia , Vias Neurais/fisiologia
12.
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
13.
Proc Natl Acad Sci U S A ; 119(46): e2120653119, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36375084

RESUMO

The COVID-19 pandemic in the United States was characterized by a partisan gap. Democrats were more concerned about this novel health threat, more willing to socially distance, and more likely to support policies aimed at mitigating the spread of the virus than Republicans. In cross-sectional analyses of three nationally representative survey waves in 2020, we find that adverse experience with COVID-19 is associated with a narrowing of the partisan gap. The mean difference between Republicans and Democrats in concern, policy support, and behavioral intentions narrows or even disappears at high levels of self-reported adverse experience. Reported experience does not depend on party affiliation and is predicted by local COVID-19 incidence rates. In contrast, analyses of longitudinal data and county-level incidence rates do not show a consistent relationship among experience, partisanship, and behavior or policy support. Our findings suggest that self-reported personal experience interacts with partisanship in complex ways and may be an important channel for concern about novel threats such as the COVID-19 pandemic. We find consistent results for self-reported experience of extreme weather events and climate change attitudes and policy preferences, although the association between extreme weather and experience and climate change is more tenuous.


Assuntos
COVID-19 , Humanos , Estados Unidos/epidemiologia , COVID-19/epidemiologia , Pandemias , Política , Mudança Climática , Estudos Transversais
14.
J Neurosci ; 43(19): 3495-3508, 2023 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-37028934

RESUMO

Selectivity for direction of motion is a key feature of primary visual cortical neurons. Visual experience is required for direction selectivity in carnivore and primate visual cortex, but the circuit mechanisms of its formation remain incompletely understood. Here, we examined how developing lateral geniculate nucleus (LGN) neurons may contribute to cortical direction selectivity. Using in vivo electrophysiology techniques, we examined LGN receptive field properties of visually naive female ferrets before and after exposure to 6 h of motion stimuli to assess the effect of acute visual experience on LGN cell development. We found that acute experience with motion stimuli did not significantly affect the weak orientation or direction selectivity of LGN neurons. In addition, we found that neither latency nor sustainedness or transience of LGN neurons significantly changed with acute experience. These results suggest that the direction selectivity that emerges in cortex after acute experience is computed in cortex and cannot be explained by changes in LGN cells.SIGNIFICANCE STATEMENT The development of typical neural circuitry requires experience-independent and experience-dependent factors. In the visual cortex of carnivores and primates, selectivity for motion arises as a result of experience, but we do not understand whether the major brain area that sits between the retina and the visual cortex-the lateral geniculate nucleus of the thalamus-also participates. Here, we found that lateral geniculate neurons do not exhibit changes as a result of several hours of visual experience with moving stimuli at a time when visual cortical neurons undergo a rapid change. We conclude that lateral geniculate neurons do not participate in this plasticity and that changes in cortex are likely responsible for the development of direction selectivity in carnivores and primates.


Assuntos
Corpos Geniculados , Córtex Visual , Animais , Feminino , Corpos Geniculados/fisiologia , Furões , Tálamo , Neurônios/fisiologia , Córtex Visual/fisiologia , Estimulação Luminosa/métodos , Vias Visuais/fisiologia
15.
J Neurosci ; 43(35): 6141-6163, 2023 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-37541836

RESUMO

Mouse ultrasonic vocalizations (USVs) contain predictable sequential structures like bird songs and speech. Neural representation of USVs in the mouse primary auditory cortex (Au1) and its plasticity with experience has been largely studied with single-syllables or dyads, without using the predictability in USV sequences. Studies using playback of USV sequences have used randomly selected sequences from numerous possibilities. The current study uses mutual information to obtain context-specific natural sequences (NSeqs) of USV syllables capturing the observed predictability in male USVs in different contexts of social interaction with females. Behavioral and physiological significance of NSeqs over random sequences (RSeqs) lacking predictability were examined. Female mice, never having the social experience of being exposed to males, showed higher selectivity for NSeqs behaviorally and at cellular levels probed by expression of immediate early gene c-fos in Au1. The Au1 supragranular single units also showed higher selectivity to NSeqs over RSeqs. Social-experience-driven plasticity in encoding NSeqs and RSeqs in adult females was probed by examining neural selectivities to the same sequences before and after the above social experience. Single units showed enhanced selectivity for NSeqs over RSeqs after the social experience. Further, using two-photon Ca2+ imaging, we observed social experience-dependent changes in the selectivity of sequences of excitatory and somatostatin-positive inhibitory neurons but not parvalbumin-positive inhibitory neurons of Au1. Using optogenetics, somatostatin-positive neurons were identified as a possible mediator of the observed social-experience-driven plasticity. Our study uncovers the importance of predictive sequences and introduces mouse USVs as a promising model to study context-dependent speech like communications.SIGNIFICANCE STATEMENT Humans need to detect patterns in the sensory world. For instance, speech is meaningful sequences of acoustic tokens easily differentiated from random ordered tokens. The structure derives from the predictability of the tokens. Similarly, mouse vocalization sequences have predictability and undergo context-dependent modulation. Our work investigated whether mice differentiate such informative predictable sequences (NSeqs) of communicative significance from RSeqs at the behavioral, molecular, and neuronal levels. Following a social experience in which NSeqs occur as a crucial component, mouse auditory cortical neurons become more sensitive to differences between NSeqs and RSeqs, although preference for individual tokens is unchanged. Thus, speech-like communication and its dysfunction may be studied in circuit, cellular, and molecular levels in mice.


Assuntos
Córtex Auditivo , Humanos , Animais , Camundongos , Feminino , Masculino , Córtex Auditivo/fisiologia , Ultrassom/métodos , Vocalização Animal/fisiologia , Neurônios
16.
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
17.
Neuroimage ; 299: 120846, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39260780

RESUMO

Individuals' affective experience can be intricate, influenced by various factors including monetary rewards and social factors during social interaction. However, within this array of factors, divergent evidence has been considered as potential contributors to social anxiety. To gain a better understanding of the specific factors associated with anxiety during social interaction, we combined a social interaction task with neurophysiological recordings obtained through an anxiety-elicitation task conducted in a Virtual Reality (VR) environment. Employing inter-subject representational similarity analysis (ISRSA), we explored the potential linkage between individuals' anxiety neural patterns and their affective experiences during social interaction. Our findings suggest that, after controlling for other factors, the influence of the partner's emotional cues on individuals' affective experiences is specifically linked to their neural pattern of anxiety. This indicates that the emergence of anxiety during social interaction may be particularly associated with the emotional cues provided by the social partner, rather than individuals' own reward or prediction errors during social interaction. These results provide further support for the cognitive theory of social anxiety and extend the application of VR in future cognitive and affective studies.


Assuntos
Ansiedade , Recompensa , Interação Social , Realidade Virtual , Humanos , Masculino , Feminino , Ansiedade/fisiopatologia , Ansiedade/psicologia , Adulto Jovem , Adulto , Eletroencefalografia , Encéfalo/fisiologia , Encéfalo/fisiopatologia , Sinais (Psicologia)
18.
Neuroimage ; 298: 120759, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39067553

RESUMO

During fainting, disconnected consciousness may emerge in the form of dream-like experiences. Characterized by extra-ordinary and mystical features, these subjective experiences have been associated to near-death-like experiences (NDEs-like). We here aim to assess brain activity during syncope-induced disconnected consciousness by means of high-density EEG monitoring. Transient loss of consciousness and unresponsiveness were induced in 27 healthy volunteers through hyperventilation, orthostasis, and Valsalva maneuvers. Upon awakening, subjects were asked to report memories, if any. The Greyson NDE scale was used to evaluate the potential phenomenological content experienced during the syncope-induced periods of unresponsiveness. EEG source reconstruction assessed cortical activations during fainting, which were regressed out with subjective reports collected upon recovery of normal consciousness. We also conducted functional connectivity, graph-theoretic and complexity analyses. High quality high-density EEG data were obtained in 22 volunteers during syncope and unresponsiveness (lasting 22±8 s). NDE-like features (Greyson NDE scale total score ≥7/32) were apparent for eight volunteers and characterized by higher activity in delta, theta and beta2 bands in temporal and frontal regions. The richness of the NDE-like content was associated with delta, theta and beta2 bands cortical current densities, in temporal, parietal and frontal lobes, including insula, right temporoparietal junction, and cingulate cortex. Our analyses also revealed a higher complexity and that networks related to delta, theta, and beta2 bands were characterized by a higher overall connectivity paralleled by a higher segregation (i.e., local efficiency) and a higher integration (i.e., global efficiency) for the NDE-like group compared to the non-NDE-like group. Fainting-induced NDE-like episodes seem to be sustained by surges of neural activity representing promising markers of disconnected consciousness.


Assuntos
Eletroencefalografia , Síncope , Humanos , Síncope/fisiopatologia , Masculino , Feminino , Adulto , Eletroencefalografia/métodos , Adulto Jovem , Estado de Consciência/fisiologia , Encéfalo/fisiopatologia
19.
Int J Cancer ; 155(5): 816-827, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38602045

RESUMO

Overexpression of HPV-oncoproteins E6 and E7 is necessary for HPV-driven cervical carcinogenesis. Hence, these oncoproteins are promising disease-specific biomarkers. We assessed the technical and operational characteristics of the 8-HPV-type OncoE6/E7 Cervical Test in different laboratories using cervical samples from HPV-positive women living with (WLWH) and without HIV. The 8-HPV-type OncoE6/E7 Test (for short: "OncoE6/E7 test") was performed in 2833 HIV-negative women and 241 WLWH attending multicentric studies in Latin America (ESTAMPA study), and in Africa (CESTA study). Oncoprotein positivity were evaluated at each testing site, according to HIV status as well as type-specific agreement with HPV-DNA results. A feedback questionnaire was given to the operators performing the oncoprotein test to evaluate their impression and acceptability regarding the test. The OncoE6/E7 test revealed a high positivity rate heterogeneity across all testing sites (I2: 95.8%, p < .01) with significant lower positivity in WLWH compared to HIV-negative women (12% vs 25%, p < .01). A similar HPV-type distribution was found between HPV DNA genotyping and oncoprotein testing except for HPV31 and 33 (moderate agreement, k = 0.57). Twenty-one laboratory technicians were trained on oncoprotein testing. Despite operators' concerns about the time-consuming procedure and perceived need for moderate laboratory experience, they reported the OncoE6/E7 test as easy to perform and user-friendly for deployment in resource-limited settings. The high positivity rate variability found across studies and subjectivity in test outcome interpretation could potentially results in oncoprotein false positive/negative, and thus the need for further refinements before implementation of the oncoprotein testing in screen-triage-and-treat approaches is warranted.


Assuntos
Detecção Precoce de Câncer , Infecções por HIV , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/virologia , Neoplasias do Colo do Útero/diagnóstico , Infecções por Papillomavirus/virologia , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/complicações , Detecção Precoce de Câncer/métodos , Infecções por HIV/virologia , Infecções por HIV/diagnóstico , Infecções por HIV/complicações , Infecções por HIV/metabolismo , Adulto , Pessoa de Meia-Idade , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo , Países em Desenvolvimento , Papillomaviridae/genética , Papillomaviridae/isolamento & purificação , América Latina/epidemiologia , DNA Viral/análise , DNA Viral/genética , África/epidemiologia
20.
Am J Epidemiol ; 193(10): 1318-1321, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-38885958

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic, and its associated mortality, morbidity, and deep social and economic impacts, was a global traumatic stressor that challenged population mental health and our de facto mental health care system in unprecedented ways. Yet, in many respects, this crisis is not new. Psychiatric epidemiologists have recognized for decades the need and unmet need of people in distress and the limits of the public mental health services in the United States. We argue that psychiatric epidemiologists have a critical role to play as we endeavor to address population mental health and draw attention to 3 areas of consideration: elevating population-based solutions; engaging equitably with lived experience; and interrogating recovery. Psychiatric epidemiology has a long history of both responding to and shaping our understanding of the relationships among psychiatric disorders and society through evolving methods and training, and the current sociohistorical moment again suggests that shifts in our practice can strengthen our field and its impact. This article is part of a Special Collection on Mental Health.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , COVID-19/psicologia , Estados Unidos/epidemiologia , Transtornos Mentais/epidemiologia , Psiquiatria/educação , SARS-CoV-2 , Epidemiologia/educação , Serviços de Saúde Mental/organização & administração , Saúde Mental , Pandemias
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