Frontiers in Neural Circuits最新文献

{"title":"Clustered architecture of ipsilateral and interhemispheric connections in macaque ventrolateral prefrontal cortex.","authors":"Danling Hu, Hangqi Li, Toru Takahata, Hisashi Tanigawa","doi":"10.3389/fncir.2025.1635105","DOIUrl":"10.3389/fncir.2025.1635105","url":null,"abstract":"<p><p>The fine-scale organization of intrinsic and extrinsic connections in the primate ventrolateral prefrontal cortex (VLPFC), a region essential for higher cognitive functions, remains poorly understood. This contrasts with, for example, the well-documented stripe-like intrinsic circuits of the dorsolateral prefrontal cortex (DLPFC). To elucidate the circuit architecture supporting VLPFC function, we investigated the spatial organization of connections targeting the caudal VLPFC (primarily area 45A) in macaque monkeys using multiple retrograde tracers. Analyzing the distribution of labeled neurons in flattened tangential sections revealed that laterally projecting connections within the same hemisphere formed distinct clusters, not only in the VLPFC but also in the DLPFC. These clusters often spanned multiple cortical layers, suggesting a columnar-like organization. The width (minor axis) of these clusters was approximately 1.2 mm. Similarly, contralateral callosal projection neurons were also arranged in clusters. Additionally, inputs originating from the superior temporal sulcus were found to arise from discrete clusters of neurons. Our findings demonstrate that both long-range ipsilateral and interhemispheric connections of the caudal VLPFC share a common, fine-scale clustered architecture. This study provides an anatomical framework for understanding the structural basis of information processing and interhemispheric coordination within this critical association cortex, suggesting that this architecture is fundamental to VLPFC's role in complex cognitive functions.</p>","PeriodicalId":12498,"journal":{"name":"Frontiers in Neural Circuits","volume":"19 ","pages":"1635105"},"PeriodicalIF":3.0,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12417498/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145039760","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spike-timing-dependent plasticity offers delay-gated oscillatory potentiation for autaptic weights.","authors":"Risa Onda, Mihoko Ishida, Kouhei Hattori, Hideaki Yamamoto, Takashi Tanii","doi":"10.3389/fncir.2025.1646317","DOIUrl":"10.3389/fncir.2025.1646317","url":null,"abstract":"<p><p>Neuronal networks in animal brains are considered to realize specific filter functions through the precise configuration of synaptic weights, which are autonomously regulated without external supervision. In this study, we employ a single Hodgkin-Huxley-type neuron with autapses as a minimum model to computationally investigate how spike-timing-dependent plasticity (STDP) adjusts synaptic weights through recurrent feedback. The results show that the weights undergo oscillatory potentiation or depression with respect to autaptic delay and high-frequency stimulation. Our findings suggest that the STDP-mediated modulation of autaptic weights, governed by autaptic delay and input frequency, may serve as a mechanism for promoting network-level synchronization in neural systems if the network contains neurons with autapses.</p>","PeriodicalId":12498,"journal":{"name":"Frontiers in Neural Circuits","volume":"19 ","pages":"1646317"},"PeriodicalIF":3.0,"publicationDate":"2025-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12414951/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145029520","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deviance detection and regularity sensitivity in dissociated neuronal cultures.","authors":"Zhuo D Zhang, Amit Yaron, Dai Akita, Tomoyo Isoguchi Shiramatsu, Zenas C Chao, Hirokazu Takahashi","doi":"10.3389/fncir.2025.1584322","DOIUrl":"10.3389/fncir.2025.1584322","url":null,"abstract":"<p><strong>Introduction: </strong>Understanding how neural networks process complex patterns of information is crucial for advancing both neuroscience and artificial intelligence. To investigate fundamental principles of neural computation, we examined whether dissociated neuronal cultures, one of the most primitive living neural networks, exhibit regularity sensitivity beyond mere stimulus-specific adaptation and deviance detection.</p><p><strong>Methods: </strong>We recorded activity to oddball electrical stimulation paradigms from dissociated rat cortical neurons cultured on high-resolution CMOS microelectrode arrays. We examined the effects of pharmacological manipulation on responses using the N-methyl-D-aspartate (NMDA) receptor antagonist. To assess regularity sensitivity, we compared neural responses between predictable periodic sequences and random sequences of stimuli.</p><p><strong>Results: </strong>In oddball electrical stimulation paradigms, we confirmed that the neuronal culture produced mismatch responses (MMRs) with true deviance detection beyond mere adaptation. These MMRs were dependent on the N-methyl-D-aspartate (NMDA) receptors, similar to mismatch negativity (MMN) in humans, which is known to have true deviance detection properties. Crucially, we also showed sensitivity to the statistical regularity of stimuli, a phenomenon previously observed only in intact brains: the MMRs in a predictable, periodic sequence were smaller than those in a commonly used sequence in which the appearance of the deviant stimulus was random and unpredictable.</p><p><strong>Discussion: </strong>These results challenge the traditional view that a hierarchically structured neural network is required to process complex temporal patterns, suggesting instead that deviant detection and regularity sensitivity are inherent properties arising from the primitive neural network. They also suggest new directions for the development of neuro-inspired artificial intelligence systems, emphasizing the importance of incorporating adaptive mechanisms and temporal dynamics in the design of neural networks.</p>","PeriodicalId":12498,"journal":{"name":"Frontiers in Neural Circuits","volume":"19 ","pages":"1584322"},"PeriodicalIF":2.9,"publicationDate":"2025-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12415055/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145029435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"How perceptual learning rewires brain connectivity: lessons from the visual system in a top-down perspective.","authors":"Alan Consorti, Alessandro Sale","doi":"10.3389/fncir.2025.1636023","DOIUrl":"10.3389/fncir.2025.1636023","url":null,"abstract":"<p><p>Neural circuits sculpt their structure and modify the strength of their connections to effectively adapt to the external stimuli throughout life. In response to practice and experience, the brain learns to distinguish previously undetectable stimulus features recurring in the external environment. The unconscious acquisition of improved perceptual abilities falls into a form of implicit learning known as perceptual learning. Despite more than a century of multidisciplinary studies, a thorough understanding of the neural mechanisms underlying perceptual learning is still missing. Increasing evidence suggests that the learning process induces global plastic remodeling across several cortical areas, tuning neural responses to changing environmental claims by reweighting the interaction between bottom-up and top-down information. Here, we will survey classic and novel findings in the field of perceptual learning research, with a particular focus on visual perceptual learning.</p>","PeriodicalId":12498,"journal":{"name":"Frontiers in Neural Circuits","volume":"19 ","pages":"1636023"},"PeriodicalIF":3.0,"publicationDate":"2025-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12415065/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145029504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Non-negative connectivity causes bow-tie architecture in neural circuits.","authors":"Zhaofan Liu, CongCong Du, KongFatt Wong-Lin, Da-Hui Wang","doi":"10.3389/fncir.2025.1574877","DOIUrl":"10.3389/fncir.2025.1574877","url":null,"abstract":"<p><p>Bow-tie architecture (BTA) is widely observed in biological neural systems, yet the underlying mechanism driving its spontaneous emergence remains unclear. In this study, we identify a novel formation mechanism by training multi-layer neural networks under biologically inspired non-negative connectivity constraints across diverse classification tasks. We show that non-negative weights reshape network dynamics by amplifying back-propagated error signals and suppressing hidden-layer activity, leading to the self-organization of BTA without pre-defined architecture. To our knowledge, this is the first demonstration that non-negativity alone can induce BTA formation. The resulting architecture confers distinct functional advantages, including lower wiring cost, robustness to scaling, and task generalizability, highlighting both its computational efficiency and biological relevance. Our findings offer a mechanistic account of BTA emergence and bridge biological structure with artificial learning principles.</p>","PeriodicalId":12498,"journal":{"name":"Frontiers in Neural Circuits","volume":"19 ","pages":"1574877"},"PeriodicalIF":3.0,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12399558/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144992052","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reward-optimizing learning using stochastic release plasticity.","authors":"Yuhao Sun, Wantong Liao, Jinhao Li, Xinche Zhang, Guan Wang, Zhiyuan Ma, Sen Song","doi":"10.3389/fncir.2025.1618506","DOIUrl":"10.3389/fncir.2025.1618506","url":null,"abstract":"<p><p>Synaptic plasticity underlies adaptive learning in neural systems, offering a biologically plausible framework for reward-driven learning. However, a question remains: how can plasticity rules achieve robustness and effectiveness comparable to error backpropagation? In this study, we introduce Reward-Optimized Stochastic Release Plasticity (RSRP), a learning framework where synaptic release is modeled as a parameterized distribution. Utilizing natural gradient estimation, we derive a synaptic plasticity learning rule that effectively adapts to maximize reward signals. Our approach achieves competitive performance and demonstrates stability in reinforcement learning, comparable to Proximal Policy Optimization (PPO), while attaining accuracy comparable with error backpropagation in digit classification. Additionally, we identify reward regularization as a key stabilizing mechanism and validate our method in biologically plausible networks. Our findings suggest that RSRP offers a robust and effective plasticity learning rule, especially in a discontinuous reinforcement learning paradigm, with potential implications for both artificial intelligence and experimental neuroscience.</p>","PeriodicalId":12498,"journal":{"name":"Frontiers in Neural Circuits","volume":"19 ","pages":"1618506"},"PeriodicalIF":3.0,"publicationDate":"2025-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12390965/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144949864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Volitional and forced running ability in mice lacking intact primary motor cortex.","authors":"Ryusei Abo, Mei Ishikawa, Rio Shinohara, Takayuki Michikawa, Itaru Imayoshi","doi":"10.3389/fncir.2025.1630932","DOIUrl":"10.3389/fncir.2025.1630932","url":null,"abstract":"<p><p>The coordination of various brain regions achieves both volitional and forced motor control, but the role of the primary motor cortex in proficient running motor control remains unclear. This study trained mice to run at high performance (>10,000 rotations per day or >2,700 rotations per hour) using a running wheel, and then assessed the effects of the removal of bilateral cortical areas including the primary motor cortex on volitional (self-initiated) and forced (externally driven) running locomotion. The control sham-operated group revealed a quick recovery of volitional running, reaching half of the maximum daily rotation in 3.9 ± 2.6 days (<i>n</i> = 10). In contrast, the cortical injury group took a significantly longer period (7.0 ± 3.3 days, <i>n</i> = 15, <i>p</i> < 0.05) to reach half of the maximum volitional daily rotation, but recovered to preoperative levels in about two weeks. Furthermore, even 3 days after surgery to remove cortical regions, the running time on a treadmill moving at 35.3 cm/s, which is difficult for naïve mice to run on, was not significantly different from that in the sham-operated group. These results suggest that the intact primary motor cortex is not necessarily required to execute trained fast-running locomotion, but rather contributes to the spontaneity of running in mice.</p>","PeriodicalId":12498,"journal":{"name":"Frontiers in Neural Circuits","volume":"19 ","pages":"1630932"},"PeriodicalIF":2.9,"publicationDate":"2025-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12391011/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144949785","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effective training procedure for a simultaneous bimanual movement task in head-fixed mice.","authors":"Kotaro Tezuka, Hironobu Osaki, Kaneyasu Nishimura, Shin-Ichiro Terada, Masanori Matsuzaki, Yoshito Masamizu","doi":"10.3389/fncir.2025.1633843","DOIUrl":"10.3389/fncir.2025.1633843","url":null,"abstract":"<p><p>Bimanual movements consist of simultaneous and nonsimultaneous movements. The neural mechanisms of unimanual and nonsimultaneous bimanual movements have been explored in rodent studies through electrophysiological recordings and calcium imaging techniques. However, the neural bases of simultaneous bimanual movements remain poorly understood because of a lack of effective training procedures for such movements in head-fixed rodents. To address this issue, we developed a task in which mice simultaneously pull right and left levers with their forelimbs in a head-fixed condition. Here, we conducted sessions with the link plate in which both levers were mechanically linked to help mice learn the importance of simultaneous bimanual movements. These sessions with the link plate enabled the mice to maintain high success rates even during independent sessions, where the right and left levers could move independently. In these independent sessions, mice were not required to pull both levers at the same time, but rather simply to hold levers simultaneously for a specific period. The mice that experienced sessions with the link plate showed a significantly higher ratio of simultaneous (i.e., lag < 20 ms) than nonsimultaneous lever pulls. In contrast, mice without experience in sessions with the link plate showed no significant increase in simultaneous over nonsimultaneous pulls. This study demonstrates the efficacy of our new task in facilitating repetitive simultaneous forelimb movements in rodents and provides a basis for understanding the neural mechanisms underlying bimanual movements.</p>","PeriodicalId":12498,"journal":{"name":"Frontiers in Neural Circuits","volume":"19 ","pages":"1633843"},"PeriodicalIF":3.0,"publicationDate":"2025-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12370711/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144949835","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Localization and connections of the tail of caudate and caudal putamen in mouse brain.","authors":"Run-Zhe Ma, Sheng-Qiang Chen, Ge Zhu, Hui-Ru Cai, Jin-Yuan Zhang, Yi-Min Peng, Dian Lian, Song-Lin Ding","doi":"10.3389/fncir.2025.1611199","DOIUrl":"10.3389/fncir.2025.1611199","url":null,"abstract":"<p><p>The neural circuits of the striatum (caudate and putamen) constitute a crucial component of the extrapyramidal motor system, and dysfunction in these circuits is correlated with significant neurological disorders including Parkinson's disease and Huntington's disease. Many previous studies in rodents revealed the neural connections of the rostral and intermediate parts of the striatum, but relatively fewer studies focused on the caudal striatum, which likely contains both the tail of caudate (CaT) and caudal putamen (PuC). In this study, we investigate the gene markers for the CaT and PuC and brain-wide afferent and efferent projections of the caudal striatum in mice using both anterograde and retrograde neural tracing methods. Some genes such as <i>prodynorphin</i>, <i>otoferlin</i>, and <i>Wolfram syndrome 1 homolog</i> are strongly expressed in CaT and PuC while some others such as neurotensin are almost exclusively expressed in CaT. The major afferent projections of the CaT originate from the substantia nigra (SN), ventral tegmental area, basolateral amygdala, parafascicular nucleus, and visual, somatosensory, auditory and parietal association cortices. The PuC receives its main inputs from the posterior intralaminar nucleus, ventroposterior medial nucleus (VPM), medial geniculate nucleus, and entorhinal, motor and auditory cortices. Both CaT and PuC neurons (including dopamine receptor 1 expressing ones) project in a rough topographical manner to the external and internal divisions of globus pallidus (GP) and SN. However, dopamine receptor 2 expressing neurons in nearly all striatal regions (including CaT and PuC) exclusively target the external GP. In conclusion, the present study has identified the mouse equivalent of the primate CaT and revealed detailed brain-wide connections of the CaT and PuC in rodent. These findings would offer new insights into the functional correlation and disease-related neural circuits related to the caudal striatum.</p>","PeriodicalId":12498,"journal":{"name":"Frontiers in Neural Circuits","volume":"19 ","pages":"1611199"},"PeriodicalIF":3.0,"publicationDate":"2025-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12358408/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144882693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Differentiation between bipolar disorder and major depressive disorder based on AMPA receptor distribution.","authors":"Sakiko Tsugawa, Yuichi Kimura, Junichi Chikazoe, Hiroki Abe, Tetsu Arisawa, Mai Hatano, Waki Nakajima, Hiroyuki Uchida, Tomoyuki Miyazaki, Yuuki Takada, Akane Sano, Kotaro Nakano, Tsuyoshi Eiro, Akira Suda, Takeshi Asami, Akitoyo Hishimoto, Hideaki Tani, Nobuhiro Nagai, Teruki Koizumi, Shinichiro Nakajima, Shunya Kurokawa, Yohei Ohtani, Kie Takahashi, Yuhei Kikuchi, Taisuke Yatomi, Ryo Mitoma, Shunsuke Tamura, Shingo Baba, Osamu Togao, Yoji Hirano, Hirotaka Kosaka, Hidehiko Okazawa, Masaru Mimura, Takuya Takahashi","doi":"10.3389/fncir.2025.1624179","DOIUrl":"10.3389/fncir.2025.1624179","url":null,"abstract":"<p><p>An accurate diagnostic method using biological indicators is critically needed for bipolar disorder (BD) and major depressive disorder (MDD). The excitatory glutamate α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) is a crucial regulator of synaptic function, and its dysregulation may play a central role in the pathophysiology of psychiatric disorders. Our recently developed positron emission tomography (PET) tracer, [¹¹C]K-2, enables the quantitative visualization of AMPAR distribution and is considered useful for characterizing synaptic phenotypes in patients with psychiatric disorders. This study aimed to develop a machine learning-based method to differentiate bipolar disorder from major depressive disorder using AMPAR density. Sixteen patients with BD and 27 patients with MDD, all in depressive episodes, underwent PET scans with [¹¹C]K-2 and structural magnetic resonance imaging. AMPAR density was estimated using the standardized uptake value ratio from 30 to 50 min after tracer injection, normalized to whole brain radioactivity. A partial least squares model was trained to predict diagnoses based on AMPAR density, and its performance was evaluated using a leave-one-pair-out cross-validation. Significant differences in AMPAR density were observed in the parietal lobe, cerebellum, and frontal lobe, notably the dorsolateral prefrontal cortex between patients with BD and patients with MDD during a depressive episode. The model achieved an area under the curve of 0.80, sensitivity of 75.0%, and specificity of 77.8%. These findings suggest that AMPAR density measured with [¹¹C]K-2 can effectively distinguish BD from MDD and may aid diagnosis, especially in patients with ambiguous symptoms or incomplete clinical presentation.</p>","PeriodicalId":12498,"journal":{"name":"Frontiers in Neural Circuits","volume":"19 ","pages":"1624179"},"PeriodicalIF":3.0,"publicationDate":"2025-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12358400/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144882692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}