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1.
Cell Rep ; 43(3): 113906, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38451812

RESUMEN

Kinesin 1 (KIF5) is one major type of motor protein in neurons, but its members' function in the intact brain remains less studied. Using in vivo two-photon imaging, we find that conditional knockout of Kif5b (KIF5B cKO) in CaMKIIα-Cre-expressing neurons shows heightened turnover and lower stability of dendritic spines in layer 2/3 pyramidal neurons with reduced spine postsynaptic density protein 95 acquisition in the mouse cortex. Furthermore, the RNA-binding protein fragile X mental retardation protein (FMRP) is translocated to the proximity of newly formed spines several hours before the spine formation events in vivo in control mice, but this preceding transport of FMRP is abolished in KIF5B cKO mice. We further find that FMRP is localized closer to newly formed spines after fear extinction, but this learning-dependent localization is disrupted in KIF5B cKO mice. Our findings provide the crucial in vivo evidence that KIF5B is involved in the dendritic targeting of synaptic proteins that underlies dendritic spine plasticity.


Asunto(s)
Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil , Síndrome del Cromosoma X Frágil , Animales , Ratones , Espinas Dendríticas/metabolismo , Extinción Psicológica , Miedo , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/metabolismo , Síndrome del Cromosoma X Frágil/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Plasticidad Neuronal
2.
J Neurophysiol ; 131(6): 1083-1100, 2024 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-38505898

RESUMEN

The striatum receives projections from multiple regions of the cerebral cortex consistent with the role of the basal ganglia in diverse motor, affective, and cognitive functions. Within the striatum, the caudate receives projections from association cortex, including multiple distinct regions of prefrontal cortex. Building on recent insights about the details of how juxtaposed cortical networks are specialized for distinct aspects of higher-order cognition, we revisited caudate organization using within-individual precision neuroimaging initially in two intensively scanned individuals (each scanned 31 times). Results revealed that the caudate has side-by-side regions that are coupled to at least five distinct distributed association networks, paralleling the organization observed in the cerebral cortex. We refer to these spatial groupings of regions as striatal association megaclusters. Correlation maps from closely juxtaposed seed regions placed within the megaclusters recapitulated the five distinct cortical networks, including their multiple spatially distributed regions. Striatal association megaclusters were explored in 15 additional participants (each scanned at least 8 times), finding that their presence generalizes to new participants. Analysis of the laterality of the regions within the megaclusters further revealed that they possess asymmetries paralleling their cortical counterparts. For example, caudate regions linked to the language network were left lateralized. These results extend the general notion of parallel specialized basal ganglia circuits with the additional discovery that, even within the caudate, there is fine-grained separation of multiple distinct higher-order networks that reflects the organization and lateralization found in the cerebral cortex.NEW & NOTEWORTHY An individualized precision neuroimaging approach reveals juxtaposed zones of the caudate that are coupled with five distinct networks in association cortex. The organization of these caudate zones recapitulates organization observed in the cerebral cortex and extends the notion of specialized basal ganglia circuits.


Asunto(s)
Núcleo Caudado , Humanos , Masculino , Adulto , Femenino , Núcleo Caudado/fisiología , Núcleo Caudado/diagnóstico por imagen , Cuerpo Estriado/fisiología , Cuerpo Estriado/diagnóstico por imagen , Corteza Cerebral/fisiología , Corteza Cerebral/diagnóstico por imagen , Imagen por Resonancia Magnética , Vías Nerviosas/fisiología , Vías Nerviosas/diagnóstico por imagen , Adulto Joven , Red Nerviosa/fisiología , Red Nerviosa/diagnóstico por imagen , Persona de Mediana Edad
3.
J Neurophysiol ; 131(6): 1014-1082, 2024 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-38489238

RESUMEN

The cerebral cortex is populated by specialized regions that are organized into networks. Here we estimated networks from functional MRI (fMRI) data in intensively sampled participants. The procedure was developed in two participants (scanned 31 times) and then prospectively applied to 15 participants (scanned 8-11 times). Analysis of the networks revealed a global organization. Locally organized first-order sensory and motor networks were surrounded by spatially adjacent second-order networks that linked to distant regions. Third-order networks possessed regions distributed widely throughout association cortex. Regions of distinct third-order networks displayed side-by-side juxtapositions with a pattern that repeated across multiple cortical zones. We refer to these as supra-areal association megaclusters (SAAMs). Within each SAAM, two candidate control regions were adjacent to three separate domain-specialized regions. Response properties were explored with task data. The somatomotor and visual networks responded to body movements and visual stimulation, respectively. Second-order networks responded to transients in an oddball detection task, consistent with a role in orienting to salient events. The third-order networks, including distinct regions within each SAAM, showed two levels of functional specialization. Regions linked to candidate control networks responded to working memory load across multiple stimulus domains. The remaining regions dissociated across language, social, and spatial/episodic processing domains. These results suggest that progressively higher-order networks nest outward from primary sensory and motor cortices. Within the apex zones of association cortex, there is specialization that repeatedly divides domain-flexible from domain-specialized regions. We discuss implications of these findings, including how repeating organizational motifs may emerge during development.NEW & NOTEWORTHY The organization of cerebral networks was estimated within individuals with intensive, repeat sampling of fMRI data. A hierarchical organization emerged in each individual that delineated first-, second-, and third-order cortical networks. Regions of distinct third-order association networks consistently exhibited side-by-side juxtapositions that repeated across multiple cortical zones, with clear and robust functional specialization among the embedded regions.


Asunto(s)
Corteza Cerebral , Imagen por Resonancia Magnética , Red Nerviosa , Humanos , Corteza Cerebral/fisiología , Corteza Cerebral/diagnóstico por imagen , Masculino , Femenino , Adulto , Red Nerviosa/fisiología , Red Nerviosa/diagnóstico por imagen , Mapeo Encefálico , Adulto Joven , Persona de Mediana Edad
4.
Eur J Neurosci ; 59(7): 1743-1752, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38238909

RESUMEN

Perirhinal cortex is a brain area that has been considered crucial for the object recognition memory (ORM). However, with the use of an ORM enhancer named RGS14414 as gain-in-function tool, we show here that frontal association cortex and not the Perirhinal cortex is essential for the ORM of objects with complex features that consisted of detailed drawing on the object surface (complex ORM). An expression of RGS14414, in rat brain frontal association cortex, induced the formation of long-term complex ORM, whereas the expression of the same memory enhancer in Perirhinal cortex failed to produce this effect. Instead, RGS14414 expression in Perirhinal cortex caused the formation of ORM of objects with simple features that consisted of the shape of object (simple ORM). Further, a selective elimination of frontal association cortex neurons by treatment with an immunotoxin Ox7-SAP completely abrogated the formation of complex ORM. Thus, our results suggest that frontal association cortex plays a key role in processing of a high-order recognition memory information in brain.


Asunto(s)
Reconocimiento en Psicología , Percepción Visual , Ratas , Animales , Reconocimiento en Psicología/fisiología , Encéfalo , Memoria a Largo Plazo
5.
Front Hum Neurosci ; 17: 1298761, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38111674

RESUMEN

Background: Transcranial static magnetic stimulation (tSMS) is a non-invasive brain stimulation technique that place a strong neodymium magnet on scalp to reduce cortical excitability. We have recently developed a new tSMS device with three magnets placed close to each other (triple tSMS) and confirmed that this new device can produce a stronger and broader static magnetic field than the conventional single tSMS. The aim of the present study was to investigate the effect of the conventional single tSMS as well as triple tSMS over the unilateral or bilateral motor association cortex (MAC) on simple and choice reaction time (SRT and CRT) task performance. Methods: There were two experiments: one involved the conventional tSMS, and the other involved the triple tSMS. In both experiments, right-handed healthy participants received each of the following stimulations for 20 min on different days: tSMS over the unilateral (left) MAC, tSMS over the bilateral MAC, and sham stimulation. The center of the stimulation device was set at the premotor cortex. The participants performed SRT and CRT tasks before, immediately after, and 15 min after the stimulation (Pre, Post 0, and Post 15). We evaluated RT, standard deviation (SD) of RT, and accuracy (error rate). Simulation was also performed to determine the spatial distribution of magnetic field induced by tSMS over the bilateral MAC. Results: The spatial distribution of induced magnetic field was centered around the PMd for both tSMS systems, and the magnetic field reached multiple regions of the MAC as well as the sensorimotor cortices for triple tSMS. SD of CRT was significantly larger at Post 0 as compared to Pre when triple tSMS was applied to the bilateral MAC. No significant findings were noted for the other conditions or variables. Discussion: We found that single tSMS over the unilateral or bilateral MAC did not affect performance of RT tasks, whereas triple tSMS over the bilateral MAC but not over the unilateral MAC increased variability of CRT. Our finding suggests that RT task performance can be modulated using triple tSMS.

6.
J Neurophysiol ; 130(6): 1602-1615, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37937340

RESUMEN

A recurring debate concerns whether regions of primate prefrontal cortex (PFC) support domain-flexible or domain-specific processes. Here we tested the hypothesis with functional MRI (fMRI) that side-by-side PFC regions, within distinct parallel association networks, differentially support domain-flexible and domain-specialized processing. Individuals (N = 9) were intensively sampled, and all effects were estimated within their own idiosyncratic anatomy. Within each individual, we identified PFC regions linked to distinct networks, including a dorsolateral PFC (DLPFC) region coupled to the medial temporal lobe (MTL) and an extended region associated with the canonical multiple-demand network. We further identified an inferior PFC region coupled to the language network. Exploration in separate task data, collected within the same individuals, revealed a robust functional triple dissociation. The DLPFC region linked to the MTL was recruited during remembering and imagining the future, distinct from juxtaposed regions that were modulated in a domain-flexible manner during working memory. The inferior PFC region linked to the language network was recruited during sentence processing. Detailed analysis of the trial-level responses further revealed that the DLPFC region linked to the MTL specifically tracked processes associated with scene construction. These results suggest that the DLPFC possesses a domain-specialized region that is small and easily confused with nearby (larger) regions associated with cognitive control. The newly described region is domain specialized for functions traditionally associated with the MTL. We discuss the implications of these findings in relation to convergent anatomical analysis in the monkey.NEW & NOTEWORTHY Competing hypotheses link regions of prefrontal cortex (PFC) to domain-flexible or domain-specific processes. Here, using a precision neuroimaging approach, we identify a domain-specialized region in dorsolateral PFC, coupled to the medial temporal lobe and recruited for scene construction. This region is juxtaposed to, but distinct from, broader PFC regions recruited flexibly for cognitive control. Region distinctions align with broader network differences, suggesting that PFC regions gain dissociable processing properties via segregated anatomical projections.


Asunto(s)
Mapeo Encefálico , Corteza Prefontal Dorsolateral , Animales , Mapeo Encefálico/métodos , Corteza Prefrontal/fisiología , Memoria a Corto Plazo/fisiología , Lóbulo Temporal/fisiología , Imagen por Resonancia Magnética/métodos
7.
Eur J Neurosci ; 58(10): 4181-4194, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37864365

RESUMEN

Conventional transcranial direct-current stimulation (tDCS) delivered to the primary motor cortex (M1) has been shown to enhance implicit motor sequence learning (IMSL). Conventional tDCS targets M1 but also the motor association cortices (MAC), making the precise contribution of these areas to IMSL presently unclear. We aimed to address this issue by comparing conventional tDCS of M1 and MAC to 4 * 1 high-definition (HD) tDCS, which more focally targets M1. In this mixed-factorial, sham-controlled, crossover study in 89 healthy young adults, we used mixed-effects models to analyse sequence-specific and general learning effects in the acquisition and short- and long-term consolidation phases of IMSL, as measured by the serial reaction time task. Conventional tDCS did not influence general learning, improved sequence-specific learning during acquisition (anodal: M = 42.64 ms, sham: M = 32.87 ms, p = .041), and seemingly deteriorated it at long-term consolidation (anodal: M = 75.37 ms, sham: M = 86.63 ms, p = .019). HD tDCS did not influence general learning, slowed performance specifically in sequential blocks across all learning phases (all p's < .050), and consequently deteriorated sequence-specific learning during acquisition (anodal: M = 24.13 ms, sham: M = 35.67 ms, p = .014) and long-term consolidation (anodal: M = 60.03 ms, sham: M = 75.01 ms, p = .002). Our findings indicate that the observed superior conventional tDCS effects on IMSL are possibly attributable to a generalized stimulation of M1 and/or adjacent MAC, rather than M1 alone. Alternatively, the differential effects can be attributed to cathodal inhibition of other cortical areas involved in IMSL by the 4 * 1 HD tDCS return electrodes, and/or more variable electric field strengths induced by HD tDCS, compared with conventional tDCS.


Asunto(s)
Corteza Motora , Estimulación Transcraneal de Corriente Directa , Adulto Joven , Humanos , Corteza Motora/fisiología , Estudios Cruzados , Aprendizaje/fisiología , Tiempo de Reacción/fisiología
8.
Neuron ; 111(20): 3270-3287.e8, 2023 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-37557180

RESUMEN

The expression of defensive responses to alerting sensory cues requires both general arousal and a specific arousal state associated with defensive emotions. However, it remains unclear whether these two forms of arousal can be regulated by common brain regions. We discovered that the medial sector of the auditory thalamus (ATm) in mice is a thalamic hub controlling both general and defensive arousal. The spontaneous activity of VGluT2-expressing ATm (ATmVGluT2+) neurons was correlated with and causally contributed to wakefulness. In sleeping mice, sustained ATmVGluT2+ population responses were predictive of sensory-induced arousal, the likelihood of which was markedly decreased by inhibiting ATmVGluT2+ neurons or multiple downstream pathways. In awake mice, ATmVGluT2+ activation led to heightened arousal accompanied by excessive anxiety and avoidance behavior. Notably, blocking their neurotransmission abolished alerting stimuli-induced defensive behaviors. These findings may shed light on the comorbidity of sleep disturbances and abnormal sensory sensitivity in specific brain disorders.


Asunto(s)
Nivel de Alerta , Tálamo , Ratones , Animales , Nivel de Alerta/fisiología , Tálamo/fisiología , Vigilia/fisiología , Neuronas/fisiología , Transmisión Sináptica
9.
Neuron ; 111(14): 2258-2273.e10, 2023 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-37196659

RESUMEN

The prefrontal cortex (PFC) has dramatically expanded in primates, but its organization and interactions with other brain regions are only partially understood. We performed high-resolution connectomic mapping of the marmoset PFC and found two contrasting corticocortical and corticostriatal projection patterns: "patchy" projections that formed many columns of submillimeter scale in nearby and distant regions and "diffuse" projections that spread widely across the cortex and striatum. Parcellation-free analyses revealed representations of PFC gradients in these projections' local and global distribution patterns. We also demonstrated column-scale precision of reciprocal corticocortical connectivity, suggesting that PFC contains a mosaic of discrete columns. Diffuse projections showed considerable diversity in the laminar patterns of axonal spread. Altogether, these fine-grained analyses reveal important principles of local and long-distance PFC circuits in marmosets and provide insights into the functional organization of the primate brain.


Asunto(s)
Callithrix , Corteza Prefrontal , Animales , Encéfalo , Corteza Cerebral , Cuerpo Estriado , Vías Nerviosas , Mapeo Encefálico
10.
J Comp Neurol ; 531(18): 1909-1925, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36592397

RESUMEN

We studied the organization of the inferior parietal cortex (IPC) in five capuchin monkey (6 hemispheres) using cytoarchitectonic (Nissl), myeloarchitectonic (Gallyas), and immune-architectonic (SMI-32 monoclonal antibody) techniques. We partitioned the IPC into five distinct areas: PFG, PG, Opt, PFop, and PGop. Since we used parasagittal sections, we were not able to study area PF due to its far lateral position, which yielded slices that were tangential to the pial surface. Areas PFG, PG, and Opt were in the convexity close to the lateral sulcus, while PFop and PGop were positioned more posteriorly, in the opercular region of IPC. Of all the five regions, area Opt was the one most similar to its analogue in the macaque, especially as revealed with SMI-32 staining. Namely, in both primate species area Opt showed a low density of large pyramidal neurons. Additionally, the apical dendrites of these neurons were sparse and vertically orientated, resembling columns. We also found area PG to be similar: both species exhibited cell body layers with a radial arrangement. On the other hand, Nissl staining revealed area PFG to be architectonically different between New and Old-World monkeys: PFG in the capuchin showed a comparatively higher cell density than in macaques, especially in layers II and IV. These results suggest that evolution may have enabled the functional specialization of these brain regions based on behavioral demands of upper limb use. The small differences in the IPC of the two primates may be linked to interspecies variability.


Asunto(s)
Cebus , Lóbulo Parietal , Animales , Macaca , Neuronas/fisiología , Mapeo Encefálico
11.
J Neurophysiol ; 129(1): 17-40, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36197013

RESUMEN

Multiple large-scale networks populate human association cortex. Here, we explored the functional properties of these networks by exploiting trial-to-trial variation in component-processing demands. In two behavioral studies (n = 136 and n = 238), participants quantified strategies used to solve individual task trials that spanned remembering, imagining future scenarios, and various control trials. These trials were also all scanned in an independent sample of functional MRI participants (n = 10), each with sufficient data to precisely define within-individual networks. Stable latent factors varied across trials and correlated with trial-level functional responses selectively across networks. One network linked to parahippocampal cortex, labeled Default Network A (DN-A), tracked scene construction, including for control trials that possessed minimal episodic memory demands. To the degree, a trial encouraged participants to construct a mental scene with imagery and awareness about spatial locations of objects or places, the response in DN-A increased. The juxtaposed Default Network B (DN-B) showed no such response but varied in relation to social processing demands. Another adjacent network, labeled Frontoparietal Network B (FPN-B), robustly correlated with trial difficulty. These results support that DN-A and DN-B are specialized networks differentially supporting information processing within spatial and social domains. Both networks are dissociable from a closely juxtaposed domain-general control network that tracks cognitive effort.NEW & NOTEWORTHY Tasks shown to differentially recruit parallel association networks are multifaceted, leaving open questions about network processes. Here, examining trial-to-trial network response properties in relation to trial traits reveals new insights into network functions. In particular, processes linked to scene construction selectively recruit a distributed network with links to parahippocampal and retrosplenial cortices, including during trials designed not to rely on the personal past. Adjacent networks show distinct patterns, providing novel evidence of functional specialization.


Asunto(s)
Corteza Cerebral , Memoria Episódica , Humanos , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/fisiología , Cognición , Recuerdo Mental/fisiología , Giro del Cíngulo , Imagen por Resonancia Magnética/métodos , Mapeo Encefálico
12.
Neuroscientist ; : 10738584221138032, 2022 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-36476177

RESUMEN

Scientific theories on the functioning and dysfunction of the human brain require an understanding of its development-before and after birth and through maturation to adulthood-and its evolution. Here we bring together several accounts of human brain evolution by focusing on the central role of oxygen and brain metabolism. We argue that evolutionary expansion of human transmodal association cortices exceeded the capacity of oxygen delivery by the vascular system, which led these brain tissues to rely on nonoxidative glycolysis for additional energy supply. We draw a link between the resulting lower oxygen tension and its effect on cytoarchitecture, which we posit as a key driver of genetic developmental programs for the human brain-favoring lower intracortical myelination and the presence of biosynthetic materials for synapse turnover. Across biological and temporal scales, this protracted capacity for neural plasticity sets the conditions for cognitive flexibility and ongoing learning, supporting complex group dynamics and intergenerational learning that in turn enabled improved nutrition to fuel the metabolic costs of further cortical expansion. Our proposed model delineates explicit mechanistic links among metabolism, molecular and cellular brain heterogeneity, and behavior, which may lead toward a clearer understanding of brain development and its disorders.

13.
J Neurosci ; 42(26): 5254-5267, 2022 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-35613891

RESUMEN

The brain areas that mediate the formation of auditory threat memory and perceptual decisions remain uncertain to date. Candidates include the primary (A1) and secondary (A2) auditory cortex, the medial division of the medial geniculate body (MGm), amygdala, and the temporal association cortex. We used chemogenetic and optogenetic manipulations with in vivo and in vitro patch-clamp recordings to assess the roles of these brain regions in threat memory learning in female mice. We found that conditioned sound (CS) frequency-dependent plasticity resulted in the formation of auditory threat memory in the temporal association cortex. This neural correlated auditory threat memory depended on CS frequency information from A1 glutamatergic subthreshold monosynaptic inputs, CS lateral inhibition from A2 glutamatergic disynaptic inputs, and non-frequency-specific facilitation from MGm glutamatergic monosynaptic inputs. These results indicate that the A2 and MGm work together in an inhibitory-facilitative role.SIGNIFICANCE STATEMENT: The ability to recognize specific sounds to avoid predators or seek prey is a useful survival tool. Improving this ability through experiential learning is an added advantage requiring neural plasticity. As an example, humans must learn to distinguish the sound of a car horn, and thus avoid oncoming traffic. Our research discovered that the temporal association cortex can encode this kind of auditory information through tonal receptive field plasticity. In addition, the results revealed the underlying synaptic mechanisms of this process. These results extended our understanding of how meaningful auditory information is processed in an animal's brain.


Asunto(s)
Corteza Auditiva , Estimulación Acústica , Amígdala del Cerebelo/fisiología , Animales , Corteza Auditiva/fisiología , Condicionamiento Clásico/fisiología , Femenino , Cuerpos Geniculados/fisiología , Ratones , Plasticidad Neuronal/fisiología
14.
Curr Biol ; 32(7): 1563-1576.e8, 2022 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-35245458

RESUMEN

Postrhinal cortex (POR) and neighboring lateral visual association areas are necessary for identifying objects and interpreting them in specific contexts, but how POR neurons encode the same object across contexts remains unclear. Here, we imaged excitatory neurons in mouse POR across tens of days prior to and throughout initial cue-reward learning and reversal learning. We assessed responses to the same cue when it was rewarded or unrewarded, during both locomotor and stationary contexts. Surprisingly, a large class of POR neurons were minimally cue-driven prior to learning. After learning, distinct clusters within this class responded selectively to a given cue when presented in a specific conjunction of reward and locomotion contexts. In addition, another class contained clusters of neurons whose cue responses were more transient, insensitive to reward learning, and adapted over thousands of presentations. These two classes of POR neurons may support context-dependent interpretation and context-independent identification of sensory cues.


Asunto(s)
Señales (Psicología) , Corteza Visual , Animales , Corteza Cerebral/fisiología , Ratones , Neuronas/fisiología , Recompensa , Corteza Visual/fisiología
15.
Biol Psychiatry Glob Open Sci ; 2(1): 17-27, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35252949

RESUMEN

BACKGROUND: A general psychopathology 'p' factor captures shared variance across mental disorders in diverse samples and may partly reflect executive dysfunction. Higher p factor scores have been related to structural alterations within the visual association cortex (VAC) and a cerebello-thalamo-cerebrocortical circuit (CTCC), both of which are important for executive control. Here, we tested replicability of these direct associations as well as the indirect role of executive functioning in a sample of healthy and cross-diagnostic adult patients. METHODS: We conducted hypothesis-driven (i.e., region-of-interest) and exploratory whole-brain structural neuroimaging analyses using data from the Consortium for Neuropsychiatric Phenomics study of 272 adults who met diagnostic criteria for schizophrenia, bipolar disorder, or attention deficit-hyperactivity disorder or were healthy controls. Using structural equation modeling, we examined direct and indirect relations between structural neural alterations (within regions-of-interest and regions identified from exploratory analyses) and p and executive function factors. RESULTS: Higher levels of p were associated with decreased executive functioning and VAC grey matter volume, replicating previous research. In contrast, we failed to replicate prior negative relations between the p factor and CTCC structure. A significant indirect relation between VAC grey matter volume and p via executive function also emerged. Whole-brain analyses identified additional structural alterations in supplementary motor area/cingulate cortex, anterior corona radiata, and corpus callosum genu related to the p factor. CONCLUSIONS: Executive dysfunction may be one mechanism underlying relations between brain structure and general psychopathology. Replication of VAC structural alterations related to p encourages further focus on this brain structure.

16.
Soc Cogn Affect Neurosci ; 17(9): 802-818, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-35086149

RESUMEN

Elaborate social interaction is a pivotal asset of the human species. The complexity of people's social lives may constitute the dominating factor in the vibrancy of many individuals' environment. The neural substrates linked to social cognition thus appear especially susceptible when people endure periods of social isolation: here, we zoom in on the systematic inter-relationships between two such neural substrates, the allocortical hippocampus (HC) and the neocortical default network (DN). Previous human social neuroscience studies have focused on the DN, while HC subfields have been studied in most detail in rodents and monkeys. To bring into contact these two separate research streams, we directly quantified how DN subregions are coherently co-expressed with specific HC subfields in the context of social isolation. A two-pronged decomposition of structural brain scans from ∼40 000 UK Biobank participants linked lack of social support to mostly lateral subregions in the DN patterns. This lateral DN association co-occurred with HC patterns that implicated especially subiculum, presubiculum, CA2, CA3 and dentate gyrus. Overall, the subregion divergences within spatially overlapping signatures of HC-DN co-variation followed a clear segregation into the left and right brain hemispheres. Separable regimes of structural HC-DN co-variation also showed distinct associations with the genetic predisposition for lacking social support at the population level.


Asunto(s)
Hipocampo , Imagen por Resonancia Magnética , Hipocampo/diagnóstico por imagen , Humanos , Neuroimagen , Red Social , Apoyo Social
17.
Cereb Cortex ; 32(8): 1608-1624, 2022 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-34518890

RESUMEN

Comparative neuroimaging has been used to identify changes in white matter architecture across primate species phylogenetically close to humans, but few have compared the phylogenetically distant species. Here, we acquired postmortem diffusion imaging data from ring-tailed lemurs (Lemur catta), black-capped squirrel monkeys (Saimiri boliviensis), and rhesus macaques (Macaca mulatta). We were able to establish templates and surfaces allowing us to investigate sulcal, cortical, and white matter anatomy. The results demonstrate an expansion of the frontal projections of the superior longitudinal fasciculus complex in squirrel monkeys and rhesus macaques compared to ring-tailed lemurs, which correlates with sulcal anatomy and the lemur's smaller prefrontal granular cortex. The connectivity of the ventral pathway in the parietal region is also comparatively reduced in ring-tailed lemurs, with the posterior projections of the inferior longitudinal fasciculus not extending toward parietal cortical areas as in the other species. In the squirrel monkeys we note a very specific occipito-parietal anatomy that is apparent in their surface anatomy and the expansion of the posterior projections of the optical radiation. Our study supports the hypothesis that the connectivity of the prefrontal-parietal regions became relatively elaborated in the simian lineage after divergence from the prosimian lineage.


Asunto(s)
Sustancia Blanca , Animales , Mapeo Encefálico/métodos , Macaca mulatta , Vías Nerviosas/anatomía & histología , Vías Nerviosas/diagnóstico por imagen , Lóbulo Parietal , Sustancia Blanca/anatomía & histología , Sustancia Blanca/diagnóstico por imagen
18.
Front Neurosci ; 15: 746894, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34720865

RESUMEN

The association cortices of the brain are essential for integrating multimodal information that subserves complex and high-order cognitive functions. To delineate the changing pattern of associative cortices can provide critical insight into brain development, aging, plasticity, and disease-triggered functional abnormalities. However, how to quantitatively characterize the association capability of the brain is elusive. Here, we developed a new method of association index (Asso) at the voxel level to quantitatively characterize the brain association ability. Using the Asso method, we found high Asso values in association cortical networks, and low values in visual and limbic networks, suggesting a pattern of significant gradient distribution in neural functions. The spatial distribution patterns of Asso show high similarities across different thresholds suggesting that Asso mapping is a threshold-free method. In addition, compared with functional connectivity strength, i.e., degree centrality method, Asso mapping showed different patterns for association cortices and primary cortices. Finally, the Asso method was applied to investigate aging effects and identified similar findings with previous studies. All these results indicated that Asso can characterize the brain association patterns effectively and open a new avenue to reveal a neural basis for development, aging, and brain disorders.

19.
J Neurophysiol ; 126(6): 2138-2157, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34817294

RESUMEN

Social interaction complexity makes humans unique. But in times of social deprivation, this strength risks exposure of important vulnerabilities. Human social neuroscience studies have placed a premium on the default network (DN). In contrast, hippocampus (HC) subfields have been intensely studied in rodents and monkeys. To bridge these two literatures, we here quantified how DN subregions systematically covary with specific HC subfields in the context of subjective social isolation (i.e., loneliness). By codecomposition using structural brain scans of ∼40,000 UK Biobank participants, loneliness was specially linked to midline subregions in the uncovered DN patterns. These association cortex patterns coincided with concomitant HC patterns implicating especially CA1 and molecular layer. These patterns also showed a strong affiliation with the fornix white matter tract and the nucleus accumbens. In addition, separable signatures of structural HC-DN covariation had distinct associations with the genetic predisposition for loneliness at the population level.NEW & NOTEWORTHY The hippocampus and default network have been implicated in rich social interaction. Yet, these allocortical and neocortical neural systems have been interrogated in mostly separate literatures. Here, we conjointly investigate the hippocampus and default network at a subregion level, by capitalizing structural brain scans from ∼40,000 participants. We thus reveal unique insights on the nature of the "lonely brain" by estimating the regimes of covariation between the hippocampus and default network at population scale.


Asunto(s)
Red en Modo Predeterminado/anatomía & histología , Predisposición Genética a la Enfermedad , Hipocampo/anatomía & histología , Soledad , Adulto , Anciano , Bases de Datos Factuales , Femenino , Fórnix/anatomía & histología , Fórnix/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Herencia Multifactorial , Núcleo Accumbens/anatomía & histología , Núcleo Accumbens/diagnóstico por imagen , Sustancia Blanca/anatomía & histología , Sustancia Blanca/diagnóstico por imagen
20.
Dev Cogn Neurosci ; 52: 101025, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34700196

RESUMEN

Children from low-socioeconomic status (SES) households on average exhibit lower academic achievement than their higher-SES peers. We investigated a novel hypothesis that differences in early-developing sensory networks-specifically the ventral visual stream (VVS), which is involved in processing visual stimuli-contribute to SES-related disparities in executive functions (EF) and academic outcomes. We used fMRI to investigate SES-related differences in neural function in children (6-8 years, n = 62) during two attentional tasks involving attention to visual information: cued attention and memory-guided attention. Recruitment of VVS during both tasks was associated with EF and academic achievement, and SES-related differences in VVS activation during cued attention were marginally explained by differences in cognitive stimulation. VVS activation during cued attention mediated SES-related differences in academic achievement. Finally, the link between VVS activation during both tasks and academic achievement was mediated by differences in EF. We extend previous work by highlighting that: (i) early-developing visual processing regions play a role in supporting complex attentional processes, (ii) childhood SES is associated with VVS function, which is explained in part by SES-related differences in cognitive stimulation and (iii) provide preliminary evidence that individual differences in VVS function may play a role in the emergence of the income-achievement gap.


Asunto(s)
Éxito Académico , Clase Social , Logro , Niño , Cognición , Función Ejecutiva/fisiología , Humanos
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