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1.
Nat Commun ; 12(1): 4816, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34376652

RESUMO

Remapping refers to a decorrelation of hippocampal representations of similar spatial environments. While it has been speculated that remapping may contribute to the resolution of episodic memory interference in humans, direct evidence is surprisingly limited. We tested this idea using high-resolution, pattern-based fMRI analyses. Here we show that activity patterns in human CA3/dentate gyrus exhibit an abrupt, temporally-specific decorrelation of highly similar memory representations that is precisely coupled with behavioral expressions of successful learning. The magnitude of this learning-related decorrelation was predicted by the amount of pattern overlap during initial stages of learning, with greater initial overlap leading to stronger decorrelation. Finally, we show that remapped activity patterns carry relatively more information about learned episodic associations compared to competing associations, further validating the learning-related significance of remapping. Collectively, these findings establish a critical link between hippocampal remapping and episodic memory interference and provide insight into why remapping occurs.


Assuntos
Potenciais de Ação/fisiologia , Região CA3 Hipocampal/fisiologia , Giro Denteado/fisiologia , Aprendizagem/fisiologia , Memória/fisiologia , Adolescente , Adulto , Mapeamento Encefálico/métodos , Região CA3 Hipocampal/diagnóstico por imagem , Giro Denteado/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Estimulação Luminosa/métodos , Adulto Jovem
2.
Neuron ; 109(16): 2616-2626.e6, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34228960

RESUMO

Vision develops rapidly during infancy, yet how visual cortex is organized during this period is unclear. In particular, it is unknown whether functional maps that organize the mature adult visual cortex are present in the infant striate and extrastriate cortex. Here, we test the functional maturity of infant visual cortex by performing retinotopic mapping with functional magnetic resonance imaging (fMRI). Infants aged 5-23 months had retinotopic maps, with alternating preferences for vertical and horizontal meridians indicating the boundaries of visual areas V1 to V4 and an orthogonal gradient of preferences from high to low spatial frequencies. The presence of multiple visual maps throughout visual cortex in infants indicates a greater maturity of extrastriate cortex than previously appreciated. The areas showed subtle age-related fine-tuning, suggesting that early maturation undergoes continued refinement. This early maturation of area boundaries and tuning may scaffold subsequent developmental changes.


Assuntos
Encéfalo/crescimento & desenvolvimento , Córtex Visual/crescimento & desenvolvimento , Campos Visuais/fisiologia , Vias Visuais/crescimento & desenvolvimento , Mapeamento Encefálico/métodos , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética/métodos , Masculino , Estimulação Luminosa/métodos
3.
Commun Biol ; 4(1): 854, 2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34244598

RESUMO

Current state-of-the-art functional magnetic resonance imaging (fMRI) offers remarkable imaging quality and resolution, yet, the intrinsic dimensionality of brain dynamics in different states (wakefulness, light and deep sleep) remains unknown. Here we present a method to reveal the low dimensional intrinsic manifold underlying human brain dynamics, which is invariant of the high dimensional spatio-temporal representation of the neuroimaging technology. By applying this intrinsic manifold framework to fMRI data acquired in wakefulness and sleep, we reveal the nonlinear differences between wakefulness and three different sleep stages, and successfully decode these different brain states with a mean accuracy across participants of 96%. Remarkably, a further group analysis shows that the intrinsic manifolds of all participants share a common topology. Overall, our results reveal the intrinsic manifold underlying the spatiotemporal dynamics of brain activity and demonstrate how this manifold enables the decoding of different brain states such as wakefulness and various sleep stages.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Imageamento por Ressonância Magnética/métodos , Rede Nervosa/fisiologia , Sono/fisiologia , Vigília/fisiologia , Algoritmos , Encéfalo/diagnóstico por imagem , Eletroencefalografia/métodos , Humanos , Modelos Neurológicos , Rede Nervosa/diagnóstico por imagem , Neuroimagem/métodos , Fases do Sono/fisiologia
4.
Commun Biol ; 4(1): 855, 2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34244604

RESUMO

The spatial-temporal sequence of cerebral blood flow (CBF), cerebral blood volume (CBV) and blood velocity changes triggered by neuronal activation is critical for understanding functional brain imaging. This sequence follows a stereotypic pattern of changes across different zones of the vasculature in the olfactory bulb, the first relay of olfaction. However, in the cerebral cortex, where most human brain mapping studies are performed, the timing of activity evoked vascular events remains controversial. Here we utilized a single whisker stimulation model to map out functional hyperemia along vascular arbours from layer II/III to the surface of primary somatosensory cortex, in anesthetized and awake Thy1-GCaMP6 mice. We demonstrate that sensory stimulation triggers an increase in blood velocity within the mid-capillary bed and a dilation of upstream large capillaries, and the penetrating and pial arterioles. We report that under physiological stimulation, response onset times are highly variable across compartments of different vascular arbours. Furthermore, generating transfer functions (TFs) between neuronal Ca2+ and vascular dynamics across different brain states demonstrates that anesthesia decelerates neurovascular coupling (NVC). This spatial-temporal pattern of vascular events demonstrates functional diversity not only between different brain regions but also at the level of different vascular arbours within supragranular layers of the cerebral cortex.


Assuntos
Encéfalo/fisiologia , Córtex Cerebral/fisiologia , Circulação Cerebrovascular/fisiologia , Acoplamento Neurovascular/fisiologia , Córtex Somatossensorial/fisiologia , Animais , Encéfalo/irrigação sanguínea , Mapeamento Encefálico/métodos , Capilares/fisiologia , Córtex Cerebral/irrigação sanguínea , Feminino , Humanos , Masculino , Camundongos Endogâmicos C57BL , Neuroimagem/métodos , Neurônios/fisiologia , Bulbo Olfatório/irrigação sanguínea , Bulbo Olfatório/fisiologia , Córtex Somatossensorial/irrigação sanguínea , Vibrissas/fisiologia , Vigília/fisiologia
5.
Commun Biol ; 4(1): 866, 2021 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-34262129

RESUMO

Animal models suggest transitions from non-addictive to addictive behavioral engagement are associated with ventral-to-dorsal striatal shifts. However, few studies have examined such features in humans, especially in internet gaming disorder (IGD), a proposed behavioral addiction. We recruited 418 subjects (174 with IGD; 244 with recreational game use (RGU)). Resting-state fMRI data were collected and functional connectivity analyses were performed based on ventral and dorsal striatal seeds. Correlations and follow-up spectrum dynamic causal model (spDCM) analyses were performed to examine relationships between the ventral/dorsal striatum and middle frontal gyrus (MFG). Longitudinal data were also analysed to investigate changes over time. IGD relative to RGU subjects showed lower ventral-striatum-to-MFG (mostly involving supplementary motor area (SMA)) and higher dorsal-striatum-to-MFG functional connectivity. spDCM revealed that left dorsal-striatum-to-MFG connectivity was correlated with IGD severity. Longitudinal data within IGD and RGU groups found greater dorsal striatal connectivity with the MFG in IGD versus RGU subjects. These findings suggest similar ventral-to-dorsal striatal shifts may operate in IGD and traditional addictions.


Assuntos
Encéfalo/fisiopatologia , Transtorno de Adição à Internet/fisiopatologia , Rede Nervosa/fisiopatologia , Vias Neurais/fisiologia , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Corpo Estriado/diagnóstico por imagem , Corpo Estriado/fisiopatologia , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Jogos Recreativos/psicologia , Humanos , Transtorno de Adição à Internet/diagnóstico por imagem , Transtorno de Adição à Internet/psicologia , Imageamento por Ressonância Magnética/métodos , Masculino , Rede Nervosa/diagnóstico por imagem , Vias Neurais/diagnóstico por imagem , Estriado Ventral/diagnóstico por imagem , Estriado Ventral/fisiopatologia , Adulto Jovem
6.
Medicine (Baltimore) ; 100(23): e26281, 2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34115028

RESUMO

BACKGROUND AND OBJECTIVE: Previous studies have shown that the default-mode network (DMN) has a substantial role in patients with major depressive disorder (MDD). However, there is a shortage of information regarding variations in the functional connectivity (FC) of the DMN of treatment-naive patients with first-episode MDD. The present study aims to explore the FC of the DMN in such patients. METHODS: The study population consisted of 33 patients and 35 controls, paired regarding age, gender, education level, and health condition. Depression severity was assessed through the Hamilton Depression Scale (HAM-D), and subjects underwent evaluation during the resting-state through functional magnetic resonance imaging (rs-fMRI). To assess the result, we used FC and ICA. We used Spearman's correlation test to detect potential correlations between anomalous FC and severity of HAM-D scores. RESULTS: We have found a decreased FC in the left medial orbitofrontal gyrus (MOFG) and right marginal gyrus (SMG) in depressive patients compared to controls. There was a negative correlation between abnormal FC in the right SMG and HAM-D scores. We have not found any increase in FC of the DMN in treatment-naive, first-episode of MDD patients. CONCLUSIONS: Our study provided evidence of a negative correlation between abnormal FC in the DMN and severity of depression symptoms measured by HAM-D in treatment-naive MDD patients. This finding could shed some light on the relevance of DMN for understanding the pathophysiology of cognitive impairment in MDD.


Assuntos
Mapeamento Encefálico/métodos , Rede de Modo Padrão/fisiopatologia , Transtorno Depressivo Maior , Imageamento por Ressonância Magnética/métodos , Córtex Pré-Frontal , Adulto , Cognição/fisiologia , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/fisiopatologia , Conectoma/métodos , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/fisiopatologia , Transtorno Depressivo Maior/psicologia , Feminino , Humanos , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiopatologia , Escalas de Graduação Psiquiátrica
7.
Commun Biol ; 4(1): 741, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34131279

RESUMO

Spontaneous neural activity fluctuations have been shown to influence trial-by-trial variation in perceptual, cognitive, and behavioral outcomes. However, the complex electrophysiological mechanisms by which these fluctuations shape stimulus-evoked neural activity remain largely to be explored. Employing a large-scale magnetoencephalographic dataset and an electroencephalographic replication dataset, we investigate the relationship between spontaneous and evoked neural activity across a range of electrophysiological variables. We observe that for high-frequency activity, high pre-stimulus amplitudes lead to greater evoked desynchronization, while for low frequencies, high pre-stimulus amplitudes induce larger degrees of event-related synchronization. We further decompose electrophysiological power into oscillatory and scale-free components, demonstrating different patterns of spontaneous-evoked correlation for each component. Finally, we find correlations between spontaneous and evoked time-domain electrophysiological signals. Overall, we demonstrate that the dynamics of multiple electrophysiological variables exhibit distinct relationships between their spontaneous and evoked activity, a result which carries implications for experimental design and analysis in non-invasive electrophysiology.


Assuntos
Mapeamento Encefálico/métodos , Ondas Encefálicas/fisiologia , Potenciais Evocados/fisiologia , Estado de Consciência/fisiologia , Eletroencefalografia , Fenômenos Eletrofisiológicos/fisiologia , Humanos , Magnetoencefalografia
8.
Commun Biol ; 4(1): 746, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34135466

RESUMO

Our brain constructs reality through narrative and argumentative thought. Some hypotheses argue that these two modes of cognitive functioning are irreducible, reflecting distinct mental operations underlain by separate neural bases; Others ascribe both to a unitary neural system dedicated to long-timescale information. We addressed this question by employing inter-subject measures to investigate the stimulus-induced neural responses when participants were listening to narrative and argumentative texts during fMRI. We found that following both kinds of texts enhanced functional couplings within the frontoparietal control system. However, while a narrative specifically implicated the default mode system, an argument specifically induced synchronization between the intraparietal sulcus in the frontoparietal control system and multiple perisylvian areas in the language system. Our findings reconcile the two hypotheses by revealing commonalities and differences between the narrative and the argumentative brain networks, showing how diverse mental activities arise from the segregation and integration of the existing brain systems.


Assuntos
Encéfalo/fisiologia , Cognição/fisiologia , Pensamento/fisiologia , Adulto , Idoso , Mapeamento Encefálico/métodos , Feminino , Humanos , Idioma , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Rede Nervosa/fisiologia , Adulto Jovem
9.
Nat Commun ; 12(1): 3374, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099735

RESUMO

Numerosity, the set size of a group of items, helps guide behaviour and decisions. Non-symbolic numerosities are represented by the approximate number system. However, distinct behavioural performance suggests that small numerosities, i.e. subitizing range, are implemented differently in the brain than larger numerosities. Prior work has shown that neural populations selectively responding (i.e. hemodynamic responses) to small numerosities are organized into a network of topographical maps. Here, we investigate how neural populations respond to large numerosities, well into the ANS. Using 7 T fMRI and biologically-inspired analyses, we found a network of neural populations tuned to both small and large numerosities organized within the same topographic maps. These results demonstrate a continuum of numerosity preferences that progressively cover both the subitizing range and beyond within the same numerosity map, suggesting a single neural mechanism. We hypothesize that differences in map properties, such as cortical magnification and tuning width, underlie known differences in behaviour.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Rede Nervosa/fisiologia , Percepção Visual/fisiologia , Adulto , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Estimulação Luminosa/métodos , Reprodutibilidade dos Testes
10.
J Clin Neurosci ; 89: 349-353, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34083112

RESUMO

Somnolence during brain function mapping is one of the factors that inhibit the accomplishment of the goals of awake craniotomy. We examined the effect of anesthesia depth measured by bispectral index (BIS) during pre-awake phase on somnolence during brain function mapping and also explored the factors associated with somnolence. We examined the association between BIS values during pre-awake phase and somnolence during the first 30 min of brain function mapping in 55 patients who underwent awake craniotomy at Kyoto University Hospital from 2015 to 2018. The pre-awake BIS value was defined as the mean BIS value for 60 min before the removal of the airway. Somnolence during brain function mapping was the primary outcome, defined as either of the following conditions: inability to follow up, disorientation, or inability to assess speech function. Additionally, we compared patient or perioperative variables between patients with/without somnolence. Somnolence occurred in 14 patients (25.5%), of which 6 patients (10.9%) were unable to complete brain function mapping. There was no significant difference in the pre-awake BIS value between patients with/without somnolence (median: 46 vs. 49, P = 0.192). Somnolence was not significantly associated with age, gender, and the number of preoperative anticonvulsive drugs, but patients with somnolence had a significantly lower preoperative Western Aphasia Battery (WAB) aphasia quotient score (median 93.8 vs. 98.6, P = 0.011). We did not find an association between pre-awake BIS value and somnolence during brain function mapping. Somnolence likely occurs in patients with a low preoperative WAB aphasia quotient score.


Assuntos
Mapeamento Encefálico/métodos , Craniotomia/métodos , Sonolência , Adulto , Anticonvulsivantes/efeitos adversos , Mapeamento Encefálico/efeitos adversos , Neoplasias Encefálicas/cirurgia , Craniotomia/efeitos adversos , Humanos , Pessoa de Meia-Idade , Vigília
11.
PLoS Biol ; 19(5): e3001241, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33951043

RESUMO

The study of unconscious processing requires a measure of conscious awareness. Awareness measures can be either subjective (based on participant's report) or objective (based on perceptual performance). The preferred awareness measure depends on the theoretical position about consciousness and may influence conclusions about the extent of unconscious processing and about the neural correlates of consciousness. We obtained functional magnetic resonance imaging (fMRI) measurements from 43 subjects while they viewed masked faces and houses that were either subjectively or objectively invisible. Even for objectively invisible (perceptually indiscriminable) stimuli, we found significant category information in both early, lower-level visual areas and in higher-level visual cortex, although representations in anterior, category-selective ventrotemporal areas were less robust. For subjectively invisible stimuli, similar to visible stimuli, there was a clear posterior-to-anterior gradient in visual cortex, with stronger category information in ventrotemporal cortex than in early visual cortex. For objectively invisible stimuli, however, category information remained virtually unchanged from early visual cortex to object- and category-selective visual areas. These results demonstrate that although both objectively and subjectively invisible stimuli are represented in visual cortex, the extent of unconscious information processing is influenced by the measurement approach. Furthermore, our data show that subjective and objective approaches are associated with different neural correlates of consciousness and thus have implications for neural theories of consciousness.


Assuntos
Conscientização/fisiologia , Visão Ocular/fisiologia , Percepção Visual/fisiologia , Adolescente , Adulto , Encéfalo/fisiologia , Mapeamento Encefálico/métodos , Córtex Cerebral/fisiologia , Estado de Consciência/fisiologia , Feminino , Substância Cinzenta/fisiologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Estimulação Luminosa/métodos , Córtex Visual/fisiologia , Adulto Jovem
12.
Nat Neurosci ; 24(6): 873-885, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33972801

RESUMO

Functional circuits consist of neurons with diverse axonal projections and gene expression. Understanding the molecular signature of projections requires high-throughput interrogation of both gene expression and projections to multiple targets in the same cells at cellular resolution, which is difficult to achieve using current technology. Here, we introduce BARseq2, a technique that simultaneously maps projections and detects multiplexed gene expression by in situ sequencing. We determined the expression of cadherins and cell-type markers in 29,933 cells and the projections of 3,164 cells in both the mouse motor cortex and auditory cortex. Associating gene expression and projections in 1,349 neurons revealed shared cadherin signatures of homologous projections across the two cortical areas. These cadherins were enriched across multiple branches of the transcriptomic taxonomy. By correlating multigene expression and projections to many targets in single neurons with high throughput, BARseq2 provides a potential path to uncovering the molecular logic underlying neuronal circuits.


Assuntos
Córtex Auditivo/metabolismo , Mapeamento Encefálico/métodos , Processamento Eletrônico de Dados/métodos , Redes Reguladoras de Genes/genética , Córtex Motor/metabolismo , Animais , Córtex Auditivo/química , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Córtex Motor/química , Vias Neurais/química , Vias Neurais/metabolismo
13.
Commun Biol ; 4(1): 553, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33976383

RESUMO

The formation and persistence of negative pain-related expectations by classical conditioning remain incompletely understood. We elucidated behavioural and neural correlates involved in the acquisition and extinction of negative expectations towards different threats across sensory modalities. In two complementary functional magnetic resonance imaging studies in healthy humans, differential conditioning paradigms combined interoceptive visceral pain with somatic pain (study 1) and aversive tone (study 2) as exteroceptive threats. Conditioned responses to interoceptive threat predictors were enhanced in both studies, consistently involving the insula and cingulate cortex. Interoceptive threats had a greater impact on extinction efficacy, resulting in disruption of ongoing extinction (study 1), and selective resurgence of interoceptive CS-US associations after complete extinction (study 2). In the face of multiple threats, we preferentially learn, store, and remember interoceptive danger signals. As key mediators of nocebo effects, conditioned responses may be particularly relevant to clinical conditions involving disturbed interoception and chronic visceral pain.


Assuntos
Extinção Psicológica/fisiologia , Aprendizagem/fisiologia , Dor/fisiopatologia , Adulto , Encéfalo/fisiologia , Mapeamento Encefálico/métodos , Córtex Cerebral/fisiologia , Condicionamento Clássico/fisiologia , Medo/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Dor Nociceptiva/fisiopatologia , Dor Visceral/fisiopatologia
14.
Commun Biol ; 4(1): 588, 2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-34002006

RESUMO

Dorsolateral prefrontal cortex (dlPFC) is proposed to drive brain-wide focus by biasing processing in favour of task-relevant information. A longstanding debate concerns whether this is achieved through enhancing processing of relevant information and/or by inhibiting irrelevant information. To address this, we applied transcranial magnetic stimulation (TMS) during fMRI, and tested for causal changes in information coding. Participants attended to one feature, whilst ignoring another feature, of a visual object. If dlPFC is necessary for facilitation, disruptive TMS should decrease coding of attended features. Conversely, if dlPFC is crucial for inhibition, TMS should increase coding of ignored features. Here, we show that TMS decreases coding of relevant information across frontoparietal cortex, and the impact is significantly stronger than any effect on irrelevant information, which is not statistically detectable. This provides causal evidence for a specific role of dlPFC in enhancing task-relevant representations and demonstrates the cognitive-neural insights possible with concurrent TMS-fMRI-MVPA.


Assuntos
Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Córtex Pré-Frontal/fisiologia , Estimulação Magnética Transcraniana/métodos , Adulto , Feminino , Humanos , Masculino , Análise e Desempenho de Tarefas , Adulto Jovem
15.
Medicine (Baltimore) ; 100(21): e25883, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34032700

RESUMO

BACKGROUND: Irritable bowel syndrome (IBS) is one of the most common functional gastrointestinal (GI) disorders affecting up to 11.5% of the general global population. The brain-gut axis has been shown to play an important role in the pathogenesis of IBS. Several studies confirmed that intrinsic brain abnormalities existed in patients with IBS. But, studies of abnormal regional homogeneity (ReHo) in IBS have reported inconsistent results. The objective of this protocol is to conduct a meta-analysis using the Seed-based d mapping software package to identify the most consistent and replicable findings of ReHo in IBS patients. METHOD: We will search the following three electronic databases: MEDLINE, EMBASE and Web of Science. The primary outcome will include the peak coordinates and effect sizes of differences in ReHo between patients with IBS and healthy controls from each dataset. The secondary outcomes will be the effects of age, illness severity, illness duration, and scanner field strength. The SDM approach was used to conduct voxel-wise meta-analysis. Whole-brain voxel-based jackknife sensitivity analysis was performed to conduct jackknife sensitivity analysis. A random effects model with Q statistics is used to conduct heterogeneity and publication bias between studies and meta-regression analyses were carried out to examine the effects of age, illness severity, illness duration, and scanner field strength. RESULTS: The results of this paper will be submitted to a peer-reviewed journal for publication. CONCLUSION: This research will determine the consistent pattern of alterations in ReHo in IBS patients.


Assuntos
Encéfalo/fisiopatologia , Motilidade Gastrointestinal/fisiologia , Mucosa Intestinal/fisiopatologia , Síndrome do Intestino Irritável/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Humanos , Metanálise como Assunto , Descanso/fisiologia , Índice de Gravidade de Doença , Revisões Sistemáticas como Assunto
16.
Nat Commun ; 12(1): 2909, 2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-34006833

RESUMO

The thalamus is a vital communication hub in the center of the brain and consists of distinct nuclei critical for consciousness and higher-order cortical functions. Structural and functional thalamic alterations are involved in the pathogenesis of common brain disorders, yet the genetic architecture of the thalamus remains largely unknown. Here, using brain scans and genotype data from 30,114 individuals, we identify 55 lead single nucleotide polymorphisms (SNPs) within 42 genetic loci and 391 genes associated with volumes of the thalamus and its nuclei. In an independent validation sample (n = 5173) 53 out of the 55 lead SNPs of the discovery sample show the same effect direction (sign test, P = 8.6e-14). We map the genetic relationship between thalamic nuclei and 180 cerebral cortical areas and find overlapping genetic architectures consistent with thalamocortical connectivity. Pleiotropy analyses between thalamic volumes and ten psychiatric and neurological disorders reveal shared variants for all disorders. Together, these analyses identify genetic loci linked to thalamic nuclei and substantiate the emerging view of the thalamus having central roles in cortical functioning and common brain disorders.


Assuntos
Encefalopatias/genética , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla/métodos , Polimorfismo de Nucleotídeo Único , Tálamo/metabolismo , Encefalopatias/classificação , Mapeamento Encefálico/métodos , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/metabolismo , Loci Gênicos/genética , Genoma Humano/genética , Humanos , Desequilíbrio de Ligação , Imageamento por Ressonância Magnética/métodos , Transtornos Mentais/classificação , Transtornos Mentais/genética , Locos de Características Quantitativas/genética , Núcleos Talâmicos/diagnóstico por imagem , Núcleos Talâmicos/metabolismo , Tálamo/diagnóstico por imagem
17.
Nat Commun ; 12(1): 2785, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33986261

RESUMO

With the availability of cellular-resolution connectivity maps, connectomes, from the mammalian nervous system, it is in question how informative such massive connectomic data can be for the distinction of local circuit models in the mammalian cerebral cortex. Here, we investigated whether cellular-resolution connectomic data can in principle allow model discrimination for local circuit modules in layer 4 of mouse primary somatosensory cortex. We used approximate Bayesian model selection based on a set of simple connectome statistics to compute the posterior probability over proposed models given a to-be-measured connectome. We find that the distinction of the investigated local cortical models is faithfully possible based on purely structural connectomic data with an accuracy of more than 90%, and that such distinction is stable against substantial errors in the connectome measurement. Furthermore, mapping a fraction of only 10% of the local connectome is sufficient for connectome-based model distinction under realistic experimental constraints. Together, these results show for a concrete local circuit example that connectomic data allows model selection in the cerebral cortex and define the experimental strategy for obtaining such connectomic data.


Assuntos
Mapeamento Encefálico/métodos , Córtex Cerebral/fisiologia , Conectoma , Modelos Neurológicos , Animais , Humanos , Camundongos
18.
Nat Commun ; 12(1): 2519, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33947867

RESUMO

Transcranial focused ultrasound (tFUS) is a promising neuromodulation technique, but its mechanisms remain unclear. We hypothesize that if tFUS parameters exhibit distinct modulation effects in different neuron populations, then the mechanism can be understood through identifying unique features in these neuron populations. In this work, we investigate the effect of tFUS stimulation on different functional neuron types in in vivo anesthetized rodent brains. Single neuron recordings were separated into regular-spiking and fast-spiking units based on their extracellular spike shapes acquired through intracranial electrophysiological recordings, and further validated in transgenic optogenetic mice models of light-excitable excitatory and inhibitory neurons. We show that excitatory and inhibitory neurons are intrinsically different in response to ultrasound pulse repetition frequency (PRF). The results suggest that we can preferentially target specific neuron types noninvasively by tuning the tFUS PRF. Chemically deafened rats and genetically deafened mice were further tested for validating the directly local neural effects induced by tFUS without potential auditory confounds.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/citologia , Encéfalo/efeitos da radiação , Potenciais Somatossensoriais Evocados/fisiologia , Potenciais Somatossensoriais Evocados/efeitos da radiação , Neurônios/citologia , Ultrassonografia/métodos , Animais , Encéfalo/fisiologia , Eletrofisiologia , Masculino , Camundongos , Camundongos Transgênicos , Neurônios/fisiologia , Neurônios/efeitos da radiação , Optogenética , Ratos , Ratos Wistar
20.
PLoS One ; 16(4): e0234219, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33852575

RESUMO

Category-specific impairments witnessed in patients with semantic deficits have broadly dissociated into natural and artificial kinds. However, how the category of food (more specifically, fruits and vegetables) fits into this distinction has been difficult to interpret, given a pattern of deficit that has inconsistently mapped onto either kind, despite its intuitive membership to the natural domain. The present study explores the effects of a manipulation of a visual sensory (i.e., color) or functional (i.e., orientation) feature on the consequential semantic processing of fruits and vegetables (and tools, by comparison), first at the behavioral and then at the neural level. The categorization of natural (i.e., fruits/vegetables) and artificial (i.e., utensils) entities was investigated via cross-modal priming. Reaction time analysis indicated a reduction in priming for color-modified natural entities and orientation-modified artificial entities. Standard event-related potentials (ERP) analysis was performed, in addition to linear classification. For natural entities, a N400 effect at central channel sites was observed for the color-modified condition compared relative to normal and orientation conditions, with this difference confirmed by classification analysis. Conversely, there was no significant difference between conditions for the artificial category in either analysis. These findings provide strong evidence that color is an integral property to the categorization of fruits/vegetables, thus substantiating the claim that feature-based processing guides as a function of semantic category.


Assuntos
Cognição/fisiologia , Semântica , Percepção Visual/fisiologia , Adolescente , Adulto , Mapeamento Encefálico/métodos , Cor , Eletroencefalografia , Potenciais Evocados/fisiologia , Potenciais Evocados Visuais/fisiologia , Feminino , Alimentos , Frutas , Humanos , Masculino , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Adulto Jovem
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