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1.
Genes Dev ; 36(21-24): 1119-1128, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36522128

RESUMEN

The Hippo-YAP signaling pathway plays a critical role in development, homeostasis, regeneration, and tumorigenesis by converging on YAP, a coactivator for the TEAD family DNA-binding transcription factors, to regulate downstream transcription programs. Given its pivotal role as the nuclear effector of the Hippo pathway, YAP is indispensable in multiple developmental and tissue contexts. Here we report that the essentiality of YAP in liver and lung development can be genetically bypassed by simultaneous inactivation of the TEAD corepressor VGLL4. This striking antagonistic epistasis suggests that the major physiological function of YAP is to antagonize VGLL4. We further show that the YAP-VGLL4 antagonism plays a widespread role in regulating Hippo pathway output beyond normal development, as inactivation of Vgll4 dramatically enhanced intrahepatic cholangiocarcinoma formation in Nf2-deficient livers and ameliorated CCl4-induced damage in normal livers. Interestingly, Vgll4 expression is temporally regulated in development and regeneration and, in certain contexts, provides a better indication of overall Hippo pathway output than YAP phosphorylation. Together, these findings highlight the central importance of VGLL4-mediated transcriptional repression in Hippo pathway regulation and inform potential strategies to modulate Hippo signaling in cancer and regenerative medicine.


Asunto(s)
Vía de Señalización Hippo , Factores de Transcripción , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Señalizadoras YAP , Factores de Transcripción de Dominio TEA
2.
Proc Natl Acad Sci U S A ; 121(27): e2306029121, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38913894

RESUMEN

Echolocating bats are among the most social and vocal of all mammals. These animals are ideal subjects for functional MRI (fMRI) studies of auditory social communication given their relatively hypertrophic limbic and auditory neural structures and their reduced ability to hear MRI gradient noise. Yet, no resting-state networks relevant to social cognition (e.g., default mode-like networks or DMLNs) have been identified in bats since there are few, if any, fMRI studies in the chiropteran order. Here, we acquired fMRI data at 7 Tesla from nine lightly anesthetized pale spear-nosed bats (Phyllostomus discolor). We applied independent components analysis (ICA) to reveal resting-state networks and measured neural activity elicited by noise ripples (on: 10 ms; off: 10 ms) that span this species' ultrasonic hearing range (20 to 130 kHz). Resting-state networks pervaded auditory, parietal, and occipital cortices, along with the hippocampus, cerebellum, basal ganglia, and auditory brainstem. Two midline networks formed an apparent DMLN. Additionally, we found four predominantly auditory/parietal cortical networks, of which two were left-lateralized and two right-lateralized. Regions within four auditory/parietal cortical networks are known to respond to social calls. Along with the auditory brainstem, regions within these four cortical networks responded to ultrasonic noise ripples. Iterative analyses revealed consistent, significant functional connectivity between the left, but not right, auditory/parietal cortical networks and DMLN nodes, especially the anterior-most cingulate cortex. Thus, a resting-state network implicated in social cognition displays more distributed functional connectivity across left, relative to right, hemispheric cortical substrates of audition and communication in this highly social and vocal species.


Asunto(s)
Corteza Auditiva , Quirópteros , Ecolocación , Imagen por Resonancia Magnética , Animales , Quirópteros/fisiología , Corteza Auditiva/fisiología , Corteza Auditiva/diagnóstico por imagen , Ecolocación/fisiología , Red en Modo Predeterminado/fisiología , Red en Modo Predeterminado/diagnóstico por imagen , Masculino , Femenino , Red Nerviosa/fisiología , Red Nerviosa/diagnóstico por imagen
3.
Proc Natl Acad Sci U S A ; 121(29): e2307221121, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-38980906

RESUMEN

Human cognitive capacities that enable flexible cooperation may have evolved in parallel with the expansion of frontoparietal cortical networks, particularly the default network. Conversely, human antisocial behavior and trait antagonism are broadly associated with reduced activity, impaired connectivity, and altered structure of the default network. Yet, behaviors like interpersonal manipulation and exploitation may require intact or even superior social cognition. Using a reinforcement learning model of decision-making on a modified trust game, we examined how individuals adjusted their cooperation rate based on a counterpart's cooperation and social reputation. We observed that learning signals in the default network updated the predicted utility of cooperation or defection and scaled with reciprocal cooperation. These signals were weaker in callous (vs. compassionate) individuals but stronger in those who were more exploitative (vs. honest and humble). Further, they accounted for associations between exploitativeness, callousness, and reciprocal cooperation. Separately, behavioral sensitivity to prior reputation was reduced in callous but not exploitative individuals and selectively scaled with responses of the medial temporal subsystem of the default network. Overall, callousness was characterized by blunted behavioral and default network sensitivity to cooperation incentives. Exploitativeness predicted heightened sensitivity to others' cooperation but not social reputation. We speculate that both compassion and exploitativeness may reflect cognitive adaptations to social living, enabled by expansion of the default network in anthropogenesis.


Asunto(s)
Conducta Cooperativa , Humanos , Masculino , Femenino , Adulto , Motivación/fisiología , Toma de Decisiones/fisiología , Confianza/psicología , Adulto Joven , Red Nerviosa/fisiología , Empatía/fisiología , Encéfalo/fisiología , Encéfalo/diagnóstico por imagen
4.
Proc Natl Acad Sci U S A ; 121(12): e2309232121, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38466844

RESUMEN

Sociality is a defining feature of the human experience: We rely on others to ensure survival and cooperate in complex social networks to thrive. Are there brain mechanisms that help ensure we quickly learn about our social world to optimally navigate it? We tested whether portions of the brain's default network engage "by default" to quickly prioritize social learning during the memory consolidation process. To test this possibility, participants underwent functional MRI (fMRI) while viewing scenes from the documentary film, Samsara. This film shows footage of real people and places from around the world. We normed the footage to select scenes that differed along the dimension of sociality, while matched on valence, arousal, interestingness, and familiarity. During fMRI, participants watched the "social" and "nonsocial" scenes, completed a rest scan, and a surprise recognition memory test. Participants showed superior social (vs. nonsocial) memory performance, and the social memory advantage was associated with neural pattern reinstatement during rest in the dorsomedial prefrontal cortex (DMPFC), a key node of the default network. Moreover, it was during early rest that DMPFC social pattern reinstatement was greatest and predicted subsequent social memory performance most strongly, consistent with the "prioritization" account. Results simultaneously update 1) theories of memory consolidation, which have not addressed how social information may be prioritized in the learning process, and 2) understanding of default network function, which remains to be fully characterized. More broadly, the results underscore the inherent human drive to understand our vastly social world.


Asunto(s)
Mapeo Encefálico , Aprendizaje Social , Humanos , Corteza Prefrontal/diagnóstico por imagen , Encéfalo , Cognición , Descanso , Imagen por Resonancia Magnética/métodos
5.
Proc Natl Acad Sci U S A ; 121(1): e2306295121, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38150498

RESUMEN

Focusing on the upside of negative events often promotes resilience. Yet, the underlying mechanisms that allow some people to spontaneously see the good in the bad remain unclear. The broaden-and-build theory of positive emotion has long suggested that positive affect, including positivity in the face of negative events, is linked to idiosyncratic thought patterns (i.e., atypical cognitive responses). Yet, evidence in support of this view has been limited, in part, due to difficulty in measuring idiosyncratic cognitive processes as they unfold. To overcome this barrier, we applied Inter-Subject Representational Similarity Analysis to test whether and how idiosyncratic neural responding supports positive reactions to negative experience. We found that idiosyncratic functional connectivity patterns in the brain's default network while resting after a negative experience predicts more positive descriptions of the event. This effect persisted when controlling for connectivity 1) before and during the negative experience, 2) before, during, and after a neutral experience, and 3) between other relevant brain regions (i.e., the limbic system). The relationship between idiosyncratic default network responding and positive affect was largely driven by functional connectivity patterns between the ventromedial prefrontal cortex and the rest of the default network and occurred relatively quickly during rest. We identified post-encoding rest as a key moment and the default network as a key brain system in which idiosyncratic responses correspond with seeing the good in the bad.


Asunto(s)
Mapeo Encefálico , Imagen por Resonancia Magnética , Humanos , Vías Nerviosas/fisiología , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Corteza Prefrontal
6.
Proc Natl Acad Sci U S A ; 121(23): e2318641121, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38814872

RESUMEN

A balanced excitation-inhibition ratio (E/I ratio) is critical for healthy brain function. Normative development of cortex-wide E/I ratio remains unknown. Here, we noninvasively estimate a putative marker of whole-cortex E/I ratio by fitting a large-scale biophysically plausible circuit model to resting-state functional MRI (fMRI) data. We first confirm that our model generates realistic brain dynamics in the Human Connectome Project. Next, we show that the estimated E/I ratio marker is sensitive to the gamma-aminobutyric acid (GABA) agonist benzodiazepine alprazolam during fMRI. Alprazolam-induced E/I changes are spatially consistent with positron emission tomography measurement of benzodiazepine receptor density. We then investigate the relationship between the E/I ratio marker and neurodevelopment. We find that the E/I ratio marker declines heterogeneously across the cerebral cortex during youth, with the greatest reduction occurring in sensorimotor systems relative to association systems. Importantly, among children with the same chronological age, a lower E/I ratio marker (especially in the association cortex) is linked to better cognitive performance. This result is replicated across North American (8.2 to 23.0 y old) and Asian (7.2 to 7.9 y old) cohorts, suggesting that a more mature E/I ratio indexes improved cognition during normative development. Overall, our findings open the door to studying how disrupted E/I trajectories may lead to cognitive dysfunction in psychopathology that emerges during youth.


Asunto(s)
Corteza Cerebral , Cognición , Imagen por Resonancia Magnética , Humanos , Cognición/fisiología , Cognición/efectos de los fármacos , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/crecimiento & desarrollo , Corteza Cerebral/metabolismo , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/fisiología , Masculino , Imagen por Resonancia Magnética/métodos , Femenino , Adolescente , Niño , Conectoma/métodos , Alprazolam/farmacología , Receptores de GABA-A/metabolismo , Adulto Joven
7.
Proc Natl Acad Sci U S A ; 121(32): e2316021121, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39078679

RESUMEN

For the human brain to operate, populations of neurons across anatomical structures must coordinate their activity within milliseconds. To date, our understanding of such interactions has remained limited. We recorded directly from the hippocampus (HPC), posteromedial cortex (PMC), ventromedial/orbital prefrontal cortex (OFC), and the anterior nuclei of the thalamus (ANT) during two experiments of autobiographical memory processing that are known from decades of neuroimaging work to coactivate these regions. In 31 patients implanted with intracranial electrodes, we found that the presentation of memory retrieval cues elicited a significant increase of low frequency (LF < 6 Hz) activity followed by cross-regional phase coherence of this LF activity before select populations of neurons within each of the four regions increased high-frequency (HF > 70 Hz) activity. The power of HF activity was modulated by memory content, and its onset followed a specific temporal order of ANT→HPC/PMC→OFC. Further, we probed cross-regional causal effective interactions with repeated electrical pulses and found that HPC stimulations cause the greatest increase in LF-phase coherence across all regions, whereas the stimulation of any region caused the greatest LF-phase coherence between that particular region and ANT. These observations support the role of the ANT in gating, and the HPC in synchronizing, the activity of cortical midline structures when humans retrieve self-relevant memories of their past. Our findings offer a fresh perspective, with high temporal fidelity, about the dynamic signaling and underlying causal connections among distant regions when the brain is actively involved in retrieving self-referential memories from the past.


Asunto(s)
Memoria Episódica , Humanos , Masculino , Femenino , Adulto , Hipocampo/fisiología , Corteza Prefrontal/fisiología , Corteza Prefrontal/diagnóstico por imagen , Encéfalo/fisiología , Encéfalo/diagnóstico por imagen , Recuerdo Mental/fisiología , Mapeo Encefálico , Persona de Mediana Edad , Neuronas/fisiología , Núcleos Talámicos Anteriores/fisiología
8.
Annu Rev Neurosci ; 41: 277-297, 2018 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-29986165

RESUMEN

A major mystery of many types of neurological and psychiatric disorders, such as Alzheimer's disease (AD), remains the underlying, disease-specific neuronal damage. Because of the strong interconnectivity of neurons in the brain, neuronal dysfunction necessarily disrupts neuronal circuits. In this article, we review evidence for the disruption of large-scale networks from imaging studies of humans and relate it to studies of cellular dysfunction in mouse models of AD. The emerging picture is that some forms of early network dysfunctions can be explained by excessively increased levels of neuronal activity. The notion of such neuronal hyperactivity receives strong support from in vivo and in vitro cellular imaging and electrophysiological recordings in the mouse, which provide mechanistic insights underlying the change in neuronal excitability. Overall, some key aspects of AD-related neuronal dysfunctions in humans and mice are strikingly similar and support the continuation of such a translational strategy.


Asunto(s)
Enfermedad de Alzheimer/patología , Encéfalo/patología , Red Nerviosa/fisiopatología , Vías Nerviosas/fisiopatología , Animales , Encéfalo/fisiopatología , Modelos Animales de Enfermedad , Humanos , Ratones , Red Nerviosa/patología , Vías Nerviosas/patología
9.
Proc Natl Acad Sci U S A ; 120(40): e2218385120, 2023 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-37751554

RESUMEN

In the months before the 2020 U.S. election, several political campaign websites added prechecked boxes (defaults), automatically making all donations into recurring weekly contributions unless donors unchecked them. Since these changes occurred at different times for different campaigns, we use a staggered difference-in-differences design to measure the causal effects of defaults on donors' behavior. We estimate that defaults increased campaign donations by over $43 million while increasing requested refunds by almost $3 million. The weekly default only impacted weekly recurring donations, and not other donations, suggesting that donors may not have intended to make weekly donations. The longer defaults were displayed, the more money campaigns raised through weekly donations. Donors did not compensate by changing the amount they donated. We found that the default had a larger impact on smaller donors and on donors who had no prior experience with defaults, causing them to start more chains and donate a larger proportion of their money through weekly recurring donations.


Asunto(s)
Conducta de Elección , Organización de la Financiación , Política , Humanos , Internet
10.
J Neurosci ; 44(22)2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38527807

RESUMEN

Adaptive behavior relies both on specific rules that vary across situations and stable long-term knowledge gained from experience. The frontoparietal control network (FPCN) is implicated in the brain's ability to balance these different influences on action. Here, we investigate how the topographical organization of the cortex supports behavioral flexibility within the FPCN. Functional properties of this network might reflect its juxtaposition between the dorsal attention network (DAN) and the default mode network (DMN), two large-scale systems implicated in top-down attention and memory-guided cognition, respectively. Our study tests whether subnetworks of FPCN are topographically proximal to the DAN and the DMN, respectively, and how these topographical differences relate to functional differences: the proximity of each subnetwork is anticipated to play a pivotal role in generating distinct cognitive modes relevant to working memory and long-term memory. We show that FPCN subsystems share multiple anatomical and functional similarities with their neighboring systems (DAN and DMN) and that this topographical architecture supports distinct interaction patterns that give rise to different patterns of functional behavior. The FPCN acts as a unified system when long-term knowledge supports behavior but becomes segregated into discrete subsystems with different patterns of interaction when long-term memory is less relevant. In this way, our study suggests that the topographical organization of the FPCN and the connections it forms with distant regions of cortex are important influences on how this system supports flexible behavior.


Asunto(s)
Encéfalo , Red Nerviosa , Humanos , Masculino , Femenino , Adulto , Red Nerviosa/fisiología , Red Nerviosa/diagnóstico por imagen , Encéfalo/fisiología , Imagen por Resonancia Magnética , Atención/fisiología , Adulto Joven , Red en Modo Predeterminado/fisiología , Red en Modo Predeterminado/diagnóstico por imagen , Memoria a Largo Plazo/fisiología , Mapeo Encefálico/métodos , Lóbulo Parietal/fisiología , Memoria a Corto Plazo/fisiología
11.
J Neurosci ; 44(20)2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38589231

RESUMEN

The default mode network (DMN) typically deactivates to external tasks, yet supports semantic cognition. It comprises medial temporal (MT), core, and frontotemporal (FT) subsystems, but its functional organization is unclear: the requirement for perceptual coupling versus decoupling, input modality (visual/verbal), type of information (social/spatial), and control demands all potentially affect its recruitment. We examined the effect of these factors on activation and deactivation of DMN subsystems during semantic cognition, across four task-based human functional magnetic resonance imaging (fMRI) datasets, and localized these responses in whole-brain state space defined by gradients of intrinsic connectivity. FT showed activation consistent with a central role across domains, tasks, and modalities, although it was most responsive to abstract, verbal tasks; this subsystem uniquely showed more "tuned" states characterized by increases in both activation and deactivation when semantic retrieval demands were higher. MT also activated to both perceptually coupled (scenes) and decoupled (autobiographical memory) tasks and showed stronger responses to picture associations, consistent with a role in scene construction. Core DMN consistently showed deactivation, especially to externally oriented tasks. These diverse contributions of DMN subsystems to semantic cognition were related to their location on intrinsic connectivity gradients: activation was closer to the sensory-motor cortex than deactivation, particularly for FT and MT, while activation for core DMN was distant from both visual cortex and cognitive control. These results reveal distinctive yet complementary DMN responses: MT and FT support different memory-based representations that are accessed externally and internally, while deactivation in core DMN is associated with demanding, external semantic tasks.


Asunto(s)
Cognición , Red en Modo Predeterminado , Imagen por Resonancia Magnética , Semántica , Humanos , Masculino , Femenino , Adulto , Cognición/fisiología , Red en Modo Predeterminado/fisiología , Red en Modo Predeterminado/diagnóstico por imagen , Adulto Joven , Red Nerviosa/fisiología , Red Nerviosa/diagnóstico por imagen , Mapeo Encefálico/métodos , Encéfalo/fisiología , Encéfalo/diagnóstico por imagen
12.
J Neurosci ; 44(11)2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38316564

RESUMEN

We recorded directly from the orbital (oPFC) and ventromedial (vmPFC) subregions of the orbitofrontal cortex (OFC) in 22 (9 female, 13 male) epilepsy patients undergoing intracranial electroencephalography (iEEG) monitoring during an experimental task in which the participants judged the accuracy of self-referential autobiographical statements as well as valenced self-judgments (SJs). We found significantly increased high-frequency activity (HFA) in ∼13% of oPFC sites (10/18 subjects) and 16% of vmPFC sites (4/12 subjects) during both of these self-referential thought processes, with the HFA power being modulated by the content of self-referential stimuli. The location of these activated sites corresponded with the location of fMRI-identified limbic network. Furthermore, the onset of HFA in the vmPFC was significantly earlier than that in the oPFC in all patients with simultaneous recordings in both regions. In 11 patients with available depression scores from comprehensive neuropsychological assessments, we documented diminished HFA in the OFC during positive SJ trials among individuals with higher depression scores; responses during negative SJ trials were not related to the patients' depression scores. Our findings provide new temporal and anatomical information about the mode of engagement in two important subregions of the OFC during autobiographical memory and SJ conditions. Our findings from the OFC support the hypothesis that diminished brain activity during positive self-evaluations, rather than heightened activity during negative self-evaluations, plays a key role in the pathophysiology of depression.


Asunto(s)
Epilepsia , Memoria Episódica , Humanos , Masculino , Femenino , Juicio , Corteza Prefrontal/diagnóstico por imagen , Corteza Prefrontal/fisiología , Encéfalo/fisiología , Mapeo Encefálico , Imagen por Resonancia Magnética
13.
Brain ; 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38889248

RESUMEN

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.

14.
Cereb Cortex ; 34(1)2024 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-38044469

RESUMEN

Brain function changes affect cognitive functions in older adults, yet the relationship between cognition and the dynamic changes of brain networks during naturalistic stimulation is not clear. Here, we recruited the young, middle-aged and older groups from the Cambridge Center for Aging and Neuroscience to investigate the relationship between dynamic metrics of brain networks and cognition using functional magnetic resonance imaging data during movie-watching. We found six reliable co-activation pattern (CAP) states of brain networks grouped into three pairs with opposite activation patterns in three age groups. Compared with young and middle-aged adults, older adults dwelled shorter time in CAP state 4 with deactivated default mode network (DMN) and activated salience, frontoparietal and dorsal-attention networks (DAN), and longer time in state 6 with deactivated DMN and activated DAN and visual network, suggesting altered dynamic interaction between DMN and other brain networks might contribute to cognitive decline in older adults. Meanwhile, older adults showed easier transfer from state 6 to state 3 (activated DMN and deactivated sensorimotor network), suggesting that the fragile antagonism between DMN and other cognitive networks might contribute to cognitive decline in older adults. Our findings provided novel insights into aberrant brain network dynamics associated with cognitive decline.


Asunto(s)
Encéfalo , Imagen por Resonancia Magnética , Imagen por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Cognición/fisiología , Mapeo Encefálico , Red Nerviosa/diagnóstico por imagen , Red Nerviosa/fisiología
15.
Cereb Cortex ; 34(1)2024 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-38061695

RESUMEN

Self-related information is crucial in our daily lives, which has led to the proposal that there is a specific brain mechanism for processing it. Neuroimaging studies have consistently demonstrated that the default mode network (DMN) is strongly associated with the representation and processing of self-related information. However, the precise relationship between DMN activity and self-related information, particularly in terms of neural oscillations, remains largely unknown. We electrically stimulated the superior temporal and fusiform areas, using stereo-electroencephalography to investigate neural oscillations associated with elicited self-related auditory hallucinations. Twenty-two instances of auditory hallucinations were recorded and categorized into self-related and other-related conditions. Comparing oscillatory power changes within the DMN between self-related and other-related auditory hallucinations, we discovered that self-related hallucinations are associated with significantly stronger positive power changes in both alpha and gamma bands compared to other-related hallucinations. To ensure the validity of our findings, we conducted controlled analyses for factors of familiarity and clarity, which revealed that the observed effects within the DMN remain independent of these factors. These results underscore the significance of the functional role of the DMN during the processing of self-related auditory hallucinations and shed light on the relationship between self-related perception and neural oscillatory activity.


Asunto(s)
Esquizofrenia , Humanos , Red en Modo Predeterminado , Alucinaciones/complicaciones , Encéfalo , Estimulación Eléctrica , Imagen por Resonancia Magnética/métodos
16.
Cereb Cortex ; 34(7)2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-39010819

RESUMEN

Learning how others perceive us helps us tune our behavior to form adaptive relationships. But which perceptions stick with us? And when in the learning process are they codified in memory? We leveraged a popular television series-The Office-to answer these questions. Prior to their functional magnetic resonance imaging (fMRI) session, viewers of The Office reported which characters they identified with, as well as which characters they perceived another person (i.e. counterpart) was similar to. During their fMRI scan, participants found out which characters other people thought they and the counterpart were like, and also completed rest scans. Participants remembered more feedback inconsistent with their self-views (vs. views of the counterpart). Although neural activity while encoding self-inconsistent feedback did not meaningfully predict memory, returning to the inconsistent self feedback during subsequent rest did. During rest, participants reinstated neural patterns engaged while receiving self-inconsistent feedback in the dorsomedial prefrontal cortex (DMPFC). DMPFC reinstatement also quadratically predicted self-inconsistent memory, with too few or too many reinstatements compromising memory performance. Processing social feedback during rest may impact how we remember and integrate the feedback, especially when it contradicts our self-views.


Asunto(s)
Encéfalo , Imagen por Resonancia Magnética , Humanos , Masculino , Femenino , Adulto Joven , Adulto , Encéfalo/fisiología , Encéfalo/diagnóstico por imagen , Memoria/fisiología , Descanso/fisiología , Percepción Social , Corteza Prefrontal/fisiología , Corteza Prefrontal/diagnóstico por imagen , Mapeo Encefálico , Retroalimentación Psicológica/fisiología , Adolescente , Autoimagen
17.
Cereb Cortex ; 34(3)2024 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-38521993

RESUMEN

Alzheimer's disease (AD) and mild cognitive impairment (MCI) both show abnormal resting-state functional connectivity (rsFC) of default mode network (DMN), but it is unclear to what extent these abnormalities are shared. Therefore, we performed a comprehensive meta-analysis, including 31 MCI studies and 20 AD studies. MCI patients, compared to controls, showed decreased within-DMN rsFC in bilateral medial prefrontal cortex/anterior cingulate cortex (mPFC/ACC), precuneus/posterior cingulate cortex (PCC), right temporal lobes, and left angular gyrus and increased rsFC between DMN and left inferior temporal gyrus. AD patients, compared to controls, showed decreased rsFC within DMN in bilateral mPFC/ACC and precuneus/PCC and between DMN and left inferior occipital gyrus and increased rsFC between DMN and right dorsolateral prefrontal cortex. Conjunction analysis showed shared decreased rsFC in mPFC/ACC and precuneus/PCC. Compared to MCI, AD had decreased rsFC in left precuneus/PCC and between DMN and left inferior occipital gyrus and increased rsFC in right temporal lobes. MCI and AD share a decreased within-DMN rsFC likely underpinning episodic memory deficits and neuropsychiatric symptoms, but differ in DMN rsFC alterations likely related to impairments in other cognitive domains such as language, vision, and execution. This may throw light on neuropathological mechanisms in these two stages of dementia.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Enfermedad de Alzheimer/diagnóstico por imagen , Red en Modo Predeterminado , Disfunción Cognitiva/patología , Giro del Cíngulo , Lóbulo Temporal/patología , Imagen por Resonancia Magnética , Encéfalo , Mapeo Encefálico
18.
Cereb Cortex ; 34(3)2024 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-38494417

RESUMEN

During NREM sleep, hippocampal sharp-wave ripple (SWR) events are thought to stabilize memory traces for long-term storage in downstream neocortical structures. Within the neocortex, a set of distributed networks organized around retrosplenial cortex (RS-network) interact preferentially with the hippocampus purportedly to consolidate those traces. Transient bouts of slow oscillations and sleep spindles in this RS-network are often observed around SWRs, suggesting that these two activities are related and that their interplay possibly contributes to memory consolidation. To investigate how SWRs interact with the RS-network and spindles, we combined cortical wide-field voltage imaging, Electrocorticography, and hippocampal LFP recordings in anesthetized and sleeping mice. Here, we show that, during SWR, "up-states" and spindles reliably co-occur in a cortical subnetwork centered around the retrosplenial cortex. Furthermore, retrosplenial transient activations and spindles predict slow gamma oscillations in CA1 during SWRs. Together, our results suggest that retrosplenial-hippocampal interaction may be a critical pathway of information exchange between the cortex and hippocampus.


Asunto(s)
Neocórtex , Sueño de Onda Lenta , Ratones , Animales , Giro del Cíngulo , Hipocampo , Sueño
19.
Cereb Cortex ; 34(5)2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38745558

RESUMEN

Arousal state is regulated by subcortical neuromodulatory nuclei, such as locus coeruleus, which send wide-reaching projections to cortex. Whether higher-order cortical regions have the capacity to recruit neuromodulatory systems to aid cognition is unclear. Here, we hypothesized that select cortical regions activate the arousal system, which, in turn, modulates large-scale brain activity, creating a functional circuit predicting cognitive ability. We utilized the Human Connectome Project 7T functional magnetic resonance imaging dataset (n = 149), acquired at rest with simultaneous eye tracking, along with extensive cognitive assessment for each subject. First, we discovered select frontoparietal cortical regions that drive large-scale spontaneous brain activity specifically via engaging the arousal system. Second, we show that the functionality of the arousal circuit driven by bilateral posterior cingulate cortex (associated with the default mode network) predicts subjects' cognitive abilities. This suggests that a cortical region that is typically associated with self-referential processing supports cognition by regulating the arousal system.


Asunto(s)
Nivel de Alerta , Encéfalo , Cognición , Conectoma , Imagen por Resonancia Magnética , Descanso , Humanos , Nivel de Alerta/fisiología , Cognición/fisiología , Masculino , Femenino , Conectoma/métodos , Adulto , Descanso/fisiología , Encéfalo/fisiología , Encéfalo/diagnóstico por imagen , Adulto Joven , Red Nerviosa/fisiología , Red Nerviosa/diagnóstico por imagen , Vías Nerviosas/fisiología , Vías Nerviosas/diagnóstico por imagen
20.
Proc Natl Acad Sci U S A ; 119(52): e2209960119, 2022 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-36538479

RESUMEN

Sensorimotor learning is a dynamic, systems-level process that involves the combined action of multiple neural systems distributed across the brain. Although much is known about the specialized cortical systems that support specific components of action (such as reaching), we know less about how cortical systems function in a coordinated manner to facilitate adaptive behavior. To address this gap, our study measured human brain activity using functional MRI (fMRI) while participants performed a classic sensorimotor adaptation task and used a manifold learning approach to describe how behavioral changes during adaptation relate to changes in the landscape of cortical activity. During early adaptation, areas in the parietal and premotor cortices exhibited significant contraction along the cortical manifold, which was associated with their increased covariance with regions in the higher-order association cortex, including both the default mode and fronto-parietal networks. By contrast, during Late adaptation, when visuomotor errors had been largely reduced, a significant expansion of the visual cortex along the cortical manifold was associated with its reduced covariance with the association cortex and its increased intraconnectivity. Lastly, individuals who learned more rapidly exhibited greater covariance between regions in the sensorimotor and association cortices during early adaptation. These findings are consistent with a view that sensorimotor adaptation depends on changes in the integration and segregation of neural activity across more specialized regions of the unimodal cortex with regions in the association cortex implicated in higher-order processes. More generally, they lend support to an emerging line of evidence implicating regions of the default mode network (DMN) in task-based performance.


Asunto(s)
Mapeo Encefálico , Corteza Motora , Humanos , Encéfalo , Corteza Motora/diagnóstico por imagen , Imagen por Resonancia Magnética , Aprendizaje
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