Cerebral cortex最新文献

Autobiographic remembering often involves types of constructive processes for psychological experiences and hypothetical scenarios of past events. Previous psychological research revealed a range of phenomenological and functional characteristics associated with recalls of episodes with high autobiographical significance. However, neural bases of such psychological characteristics and their association with memory construction processes remain unclear. In this functional magnetic resonance imaging study, we collected autobiographical episodes from 28 young adults and their extensive metrics of phenomenological and functional characteristics related to autobiographical significance. We then sought to identify neural correlates of the psychological characteristics by measuring brain activity while participants recalled specified episodes as accurately as possible or in counterfactual simulation. Multiple-regression analysis using latent factors of psychological characteristics revealed that a factor representing autobiographical significance was associated with activation in the posterior medial memory system, including the angular cortex, precuneus, and posterior cingulate cortex, during counterfactual simulation. Furthermore, representation similarity analysis using patterns of factor scores revealed significant clusters in the posterior medial system and parts of cerebellar parcels, mainly during counterfactual simulation. These findings indicate that multidimensional psychological characteristics of episodes with autobiographical significance are associated with hypothetical constructive processes in the cortical posterior medial system and cerebellum.

The fascinating results of Lorenzi et al. (2025) suggest that the number sense is innate. Many readers might find this conclusion disturbing. Here, I explore the deep cognitive origins of this sentiment. Empiricism, I suggest, is deeply grounded in human nature. This conclusion obviously does not license us to assume that knowledge is innate, but it does suggest caution against heeding our skeptical gut reaction.

Gender differences in adaptation to high-altitude environments are evident, but the specific patterns in Tibetan brains remain unclear. We analyzed T1-weighted magnetic resonance imaging scans and neuropsychological test results from 61 male and 68 female Tibetans, with lowland Han participants as controls. Tibetan females had poorer performance than males in digit serial accumulation and forward digit span. Both Tibetan and Han males had significantly larger global gray matter volume and white matter volume than females, only Tibetan female brains contained a larger proportion of gray matter than male brains. Tibetan females (vs. males) had smaller regional gray matter volume in the left rostral middle frontal gyrus and pars opercularis and right caudal middle frontal gyrus, and gray matter volume in the left pars opercularis in all Tibetans had a significant positive correlation with forward digit span. Conversely, Tibetan females had greater cortical thickness in these regions, which negatively correlated with altitude. Han populations exhibited different gender-based patterns in gray matter volume and cortical thickness compared to Tibetans. These findings suggest that Tibetan female brains are more susceptible to high-altitude, and the observed gender differences in brain volume may relate to distinct neuropsychological performances.

As a unique form of empathy, pain empathy often has a close relationship with society and morality. Research has revealed that moral emotions can influence pain empathy. The underlying physiological mechanism still needs to be further examined to understand how moral emotions affect pain empathy. This study employs EEG and Machine Learning techniques, using a painful image induction paradigm to explore the impact of moral emotion (guilt)-on pain empathy and its neural mechanisms. Participants without pain sensation were instructed to observe and evaluate pictures of an anonymous hand in painful or non-painful pictures under feelings of guilt or neutral emotion. Results found slower reaction times and higher pain ratings for painful pictures. Furthermore, guilt led to higher pain ratings. Under conditions of painful pictures, guilt-induced greater P3(350-450ms) amplitudes and higher α oscillations and enhanced the functional connectivity between the prefrontal cortex, the central frontal region, and the parieto-occipital lobe. K-nearest neighbor can effectively classify high and low-pain empathy under guilt emotion. The result showed that guilt promotes the brain's processing of painful picture, causing individuals to pay high attention and engage in deep cognitive processing. This study provides insights into enhancing empathy and fostering interpersonal relationships.

Creativity is a multifaceted cognitive process that can be driven by either malevolent or benevolent intentions, leading to divergent social outcomes. There is still uncertainty about the similarities and differences in the underlying neural activities of creativity associated with malevolent and benevolent intentions. This study investigates how intentions shape creative ideation using functional magnetic resonance imaging during malevolent and benevolent creative tasks. Key findings include: (i) overlapping activation in the middle frontal gyrus and superior frontal gyrus across tasks, indicating a shared neural basis for creative thinking; (ii) distinct activation patterns, with the malevolent creative task showing greater activation and reduced functional connectivity in regions such as the right rolandic operculum and supramarginal gyrus compared to the benevolent creative task; (iii) similar neural activity patterns in regions like the middle frontal gyrus and lingual gyrus between the malevolent creative task and benevolent creative task may indicate overlapping cognitive processes. (iv) Correlations between task-specific neural activity and behavioral performance, including malevolence negatively correlating with functional connectivity in the rolandic operculum and middle cingulate cortex during the malevolent creative task, and benevolence correlating with functional connectivity in the parahippocampal gyrus and insula during the benevolent creative task. This study indicated distinct and shared neural correlates linked to malevolent and benevolent creativity.

The microgravity environment results in transient changes in sensorimotor behavior upon astronauts' return to Earth; the effects on behavior inflight are less understood. We examined whether adaptation to sensory conflict is disrupted in microgravity, suggesting competition for adaptive resources. We evaluated sensorimotor adaptation pre-, in-, and post-flight, as well as functional brain changes at pre- and post-flight, in astronauts participating in International Space Station missions. Astronauts (n = 13) performed this task pre- and four times post-flight within an MRI scanner and performed the task three times in microgravity during a 6-mo mission. We collected behavioral data from Earth-bound controls (n = 13) along the same timeline. Astronauts displayed no change in adaptation from pre- to inflight or following their return to Earth. They showed greater aftereffects of adaptation inflight; controls did not. Astronauts also displayed increased brain activity from pre- to post-flight. These increases did not return to baseline levels until 90 d post-flight. This pattern of brain activity may reflect compensation, allowing astronauts to maintain pre-flight performance levels. These findings indicate that microgravity does not alter short-term visuomotor adaptation; however, it does affect de-adaptation, and post-flight sensorimotor neural activation can take up to 90 d to return to pre-flight levels.

Concurrent application of transcranial alternating current stimulation over distant cortical regions has been shown to modulate functional connectivity between stimulated regions; however, the precise mechanisms remain unclear. Here, we investigated how bifocal transcranial alternating current stimulation applied over the bilateral primary sensorimotor cortices modulates connectivity between the left and right primary motor cortices (M1). Using a cross-over sham-controlled triple-blind design, 37 (27 female, age: 18 to 37 yrs) healthy participants received transcranial alternating current stimulation (1.0 mA, 20 Hz, 20 min) over the bilateral sensorimotor cortices. Before and after transcranial alternating current stimulation, functional connectivity between the left and right M1s was assessed using imaginary coherence measured via resting-state electroencephalography and interhemispheric inhibition via dual-site transcranial magnetic stimulation protocol. Additionally, manual dexterity was assessed using the Purdue pegboard task. While imaginary coherence remained unchanged after stimulation, beta (20 Hz) power decreased during the transcranial alternating current stimulation session. Bifocal transcranial alternating current stimulation but not sham strengthened interhemispheric inhibition between the left and right M1s and improved bimanual assembly performance. These results suggest that improvement in bimanual performance may be explained by modulation in interhemispheric inhibition, rather than by coupling in the oscillatory activity. As functional connectivity underlies many clinical symptoms in neurological and psychiatric disorders, these findings are invaluable in developing noninvasive therapeutic interventions that target neural networks to alleviate symptoms.

The prefrontal cortex regulates emotions and is influenced by serotonin. Rodents lacking the serotonin transporter (5-HTT) show increased anxiety and changes in excitatory and inhibitory cell markers in the prefrontal cortex. However, these observations are constrained by limitations in brain representation and cell segmentation, as standard immunohistochemistry is inadequate to consider volume variations in regions of interest. We utilized the deep learning network of the StarDist method in combination with novel open-source methods for automated cell counts in a wide range of prefrontal cortex subregions. We found that 5-HTT knockout rats displayed increased anxiety and diminished relative numbers of subclass excitatory VGluT2+ and activated ΔFosB+ cells in the infralimbic and prelimbic cortices and of inhibitory GAD67+ cells in the prelimbic cortex. Anxiety levels and ΔFosB cell counts were positively correlated in wild-type, but not in knockout, rats. In conclusion, we present a novel method to quantify whole brain subregions of multilabeled cells in animal models and demonstrate reduced excitatory and inhibitory neuronal marker expression in prefrontal cortex subregions of 5-HTT knockout rats.

Maple syrup urine disease is a rare metabolic disorder that results in neurodevelopmental injury despite dietary therapy. While structural neuroimaging has shown a characteristic pattern of edema and white matter injury, no functional neuroimaging studies of maple syrup urine disease have been performed. Using widefield optical imaging, we investigated resting-state functional connectivity in two brain-specific mouse models of maple syrup urine disease (an astrocyte-specific knockout and a whole-brain knockout). At 8 weeks, mouse functional neuroimaging was performed using a custom-built widefield optical imaging system. Imaging was performed before and after initiation of a high-protein diet for 1 week to mimic metabolic crisis, which we hypothesized would result in decreased functional connectivity strength. Data were analyzed using seed-based functional connectivity and cluster-based inference. Astrocyte-specific knockout mice developed increased contralateral functional connectivity within the posteromedial somatosensory cortex after diet initiation. Whole-brain knockout mice had a similar pattern present at baseline, which persisted after diet initiation. Thus, contrary to expectations, maple syrup urine disease resulted in increased functional connectivity strength, especially after diet initiation. While the underlying etiology of these changes is unclear, these results demonstrate that inborn errors of metabolism result in changes to functional connectivity networks. Further research may demonstrate functional neuroimaging biomarkers that could be translated to clinical care.

Qualitatively different topographical patterns of connections are thought to underlie individual differences in thought and behavior, particularly at heteromodal association areas. As such, we hypothesized that connections unique to 16p11.2 deletion carriers compared to controls, rather than hyper- or hypo-connectivity, would serve as a better model to explain the cognitive and behavioral changes observed in individuals carrying this autism-risk copy number variation. Using a spatially-unbiased, data-driven approach we found that differential links clustered non-uniformly across the cortex-particularly at the superior temporal gyrus and sulcus, posterior insula, cingulate sulcus, and inferior parietal lobule bilaterally. At these hotspots, altered local connectivity that spanned across the borders of cortical large-scale networks coincided with aberrant distant interconnectivity between large-scale networks. This was most evident between the auditory and the dorsomedial default (DNb) networks-such that greater between-network interconnectivity was associated with greater communication and social impairment. Entangled connectivity between large-scale networks may preclude each network from having the necessary fidelity to operate properly, particularly when the 2 networks have opposing organization principles-namely, local specialization (segregation) versus global coherency (integration).