Frontiers in neuroimaging最新文献

{"title":"Distinct retinal oxygenation patterns in acute zonal occult outer retinopathy assessed by multimodal imaging.","authors":"Scott Tschuppert, Christophe Valmaggia, Margarita G Todorova","doi":"10.3389/fnimg.2026.1902215","DOIUrl":"10.3389/fnimg.2026.1902215","url":null,"abstract":"<p><strong>Purpose: </strong>Acute zonal occult outer retinopathy (AZOOR) is a rare outer retinal disorder that may mimic inherited retinal dystrophy. This study revises a retrospective AZOOR case series by integrating retinal oximetry as a metabolic imaging biomarker and comparing the oximetry findings with retinitis pigmentosa (RP) and healthy control data.</p><p><strong>Methods: </strong>Seven consecutive patients diagnosed with AZOOR at HOCH Health Ostschweiz in St. Gallen, Switzerland were retrospectively reviewed. Multimodal assessment included best-corrected visual acuity, fundus examination, spectral-domain optical coherence tomography (SD-OCT), fundus autofluorescence (FAF), near-infrared reflectance (NIR-R), fluorescein angiography, visual field testing, multifocal electroretinography (mfERG), full-field electroretinography (ffERG), laboratory work-up, and magnetic resonance imaging. Retinal vessel oxygen saturation data (arteriolar: A-SO<sub>2</sub>, venular: V-SO<sub>2</sub> and their difference: A-V SO<sub>2</sub>) were available in four AZOOR patients and compared with an existing institutional retinal oximetry dataset containing RP patients and healthy controls. Retinal oxygen saturation and vessel diameter were assessed using Oxymap T1 dual-wavelength retinal oximetry in a predefined peripapillary measurement area. Because of the limited AZOOR sample, all comparative analyses were exploratory.</p><p><strong>Results: </strong>The AZOOR cohort comprised seven patients (5 female, 2 male; median age 28 years, range 20-53). Six patients presented unilaterally; one patient had congenital aniridia bilaterally but AZOOR was clinically assigned to one presenting eye. Ellipsoid-zone disruption on SD-OCT was present in all affected eyes. MfERG demonstrated macular dysfunction in six of seven patients, whereas ffERG was abnormal in five of seven patients or showed normal full-field responses. Complete retinal oximetry data were available for eight eye/image measurements from four patients. Kruskal-Wallis testing across controls, RP, and AZOOR showed significant intergroup differences for A-SO<sub>2</sub> (<i>H</i> = 10.406, df = 2, <i>p</i> = 0.005) and A-V SO<sub>2</sub> (<i>H</i> = 9.538, df = 2, <i>p</i> = 0.008), but not for V-SO<sub>2</sub> (<i>H</i> = 1.002, df = 2, <i>p</i> = 0.606). Exploratory pairwise Mann-Whitney <i>U</i> tests showed lower A-SO<sub>2</sub> and lower A-V SO<sub>2</sub> in AZOOR compared with controls and RP, whereas V-SO<sub>2</sub> did not differ significantly.</p><p><strong>Conclusion: </strong>Retinal oximetry added a metabolic dimension to multimodal AZOOR assessment. In this small exploratory cohort, AZOOR showed reduced arterial saturation and reduced arteriovenous oxygen difference compared with controls and RP, whereas venous saturation was not altered. This distinct metabolic AZOOR profile indicates reduced oxygen delivery resulting in altered oxygen use contrary to the known RP pattern of increased oxygen","PeriodicalId":73094,"journal":{"name":"Frontiers in neuroimaging","volume":"5 ","pages":"1902215"},"PeriodicalIF":2.5,"publicationDate":"2026-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13597335/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149032133","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Environmental impact of portable MRI in remote Canadian settings.","authors":"Nawab Azizi, Zier Zhou, Alexander Ibrahim, Omar Islam","doi":"10.3389/fnimg.2026.1706184","DOIUrl":"10.3389/fnimg.2026.1706184","url":null,"abstract":"<p><strong>Background: </strong>Patients in remote communities often lack access to magnetic resonance imaging (MRI), necessitating long-distance transfers to tertiary centres for neuroimaging. Portable MRI (pMRI) addresses this gap by enabling bedside imaging without conventional scanner infrastructure. Its environmental profile, including energy consumption, patient transportation, and waste generation, compared with fixed MRI systems has not been comprehensively quantified in the literature.</p><p><strong>Methods: </strong>We conducted a mixed-methods analysis of an ultra-low-field pMRI scanner, focusing on three domains: (i) energy consumption, (ii) transportation-related greenhouse gas (GHG) emissions, and (iii) waste generation. Published data on energy use and emissions from 1.5 Tesla (T) and 3 T scanners were compared with modelled estimates for pMRI. Transportation emissions were calculated for patient travel between Weeneebayko General Hospital (Moose Factory, Ontario) and Kingston Health Sciences Centre (Kingston, Ontario) using commercial, charter, and air ambulance flights. Waste-related emissions were assessed based on shielding materials, helium consumption, and gadolinium-based contrast agent use.</p><p><strong>Results: </strong>pMRI consumed 11.8-17.4-fold less energy per scan than fixed 1.5 T and 3 T systems, corresponding to approximately 0.065 tons (t) CO₂ annually in a modelled 100-scan/year scenario. Based on published estimates, 56% of patients could avoid inter-facility transfer, which is estimated to reduce 14.3 t CO₂ emissions per year, equivalent to emissions from ~1.9 single-family homes. Waste analyses demonstrated that pMRI eliminated helium use, reduced shielding requirements, and minimized contrast-related waste, together preventing an additional ~5.4-9.8 t CO₂ per scanner over its lifecycle, which was equivalent to emissions produced by ~0.73-1.3 homes annually. This conservatively equates to a total carbon emissions reduction of 19.7-24.3 t per year or 2.6-3.1 home equivalents per year with pMRI implementation.</p><p><strong>Conclusion: </strong>In a remote Canadian setting, pMRI provided local neuroimaging access to a predominantly Indigenous population, with 56% of patients avoiding inter-facility transfer while maintaining diagnostic quality. These clinical benefits were accompanied by a markedly reduced carbon footprint, supporting pMRI as both a health-equity intervention and a sustainable imaging strategy for underserved, remote regions.</p>","PeriodicalId":73094,"journal":{"name":"Frontiers in neuroimaging","volume":"5 ","pages":"1706184"},"PeriodicalIF":2.5,"publicationDate":"2026-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13561834/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148957381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Repeatable tract-based diffusion metrics on a portable 64 mT MRI: a foundation for global population neuroscience.","authors":"William Royer, James Gholam, Mara Cercignani, Derek K Jones, Emre Kopanoglu","doi":"10.3389/fnimg.2026.1845201","DOIUrl":"https://doi.org/10.3389/fnimg.2026.1845201","url":null,"abstract":"<p><p>Diffusion MRI underpins much of modern population neuroscience, yet scanner access remains concentrated in high-income settings, excluding the genetic, developmental, and disease diversity needed for generalizable discovery. Portable low-field MRI systems (field strengths below 0.1 T) offer a cheaper, infrastructure-light alternative that could extend diffusion imaging to under-represented populations, but only if the measurements are sufficiently repeatable. Here we provide the first systematic test-retest evaluation of tract-based diffusion tensor MRI (DT-MRI) metrics at 64 mT. Ten healthy participants were scanned at two time-points (median interval 13 days) with an 18-direction (<i>b</i> = 900s/mm²) diffusion protocol and a <i>T</i> ₂-weighted structural sequence on a portable 64 mT scanner. After correction for distortions and gradient imperfections, diffusion tensors were estimated and constrained spherical deconvolution was performed to enable bundle-specific tractography. Tract averaged fractional anisotropy, mean diffusivity, and radial diffusivity were extracted from a selection of white-matter tracts spanning projection, association, and commissural fiber categories. Bland-Altman analysis and within-subject coefficients of variation indicated strong scan-rescan agreement, while intraclass correlation coefficients were variable across tracts and metrics. Compared with high-field data, coefficients of variation were 3-10 times larger and standard deviations in the means were approximately an order of magnitude higher. Despite this, statistical power calculations yielded feasible sample-size estimates for detecting group differences in a two-tailed <i>t</i>-test: for a 4% difference in means, approximately 25 participants per group were sufficient for the majority of tracts in MD and RD, and around 65 for FA. Although absolute DT-MRI metric values diverge from high-field references due to partial volume effects and noise-floor bias, continued advances in acquisition, reconstruction, and processing are expected to further narrow this gap. The results demonstrate that portable 64 mT MRI can deliver repeatable DT-MRI metrics, establishing a foundation for democratizing advanced neuroimaging and enabling population-scale studies in regions that have historically been excluded from brain research.</p>","PeriodicalId":73094,"journal":{"name":"Frontiers in neuroimaging","volume":"5 ","pages":"1845201"},"PeriodicalIF":2.5,"publicationDate":"2026-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13467770/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148762887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Functional neuroimaging of Cannabidiol in stress and anxiety: a systematic review.","authors":"Omar Rutledge, Richard B Goyette, Kimberly L Wang, Madelynn S Park, John D E Gabrieli","doi":"10.3389/fnimg.2026.1860919","DOIUrl":"10.3389/fnimg.2026.1860919","url":null,"abstract":"<p><p>Cannabidiol (CBD) is a non-intoxicating phytocannabinoid primarily derived from hemp (<i>cannabis sativa</i> L.) that has been investigated for its potential anxiolytic effects. Prior functional neuroimaging studies suggest that CBD may affect brain regions associated with stress and anxiety. However, it remains unclear if there is a consistent pattern of modulation within these regions and if there is a correlation with behavioral or physiological measures. We conducted a systematic review examining adult human neuroimaging investigations comparing CBD with placebo under conditions related to stress or anxiety. We searched PubMed, Web of Science, EBSCO, and ProQuest for studies published before June 30, 2025. The quality of the evidence was assessed with the revised Cochrane Risk of Bias Tool for Randomized Trials (RoB 2), findings were summarized using a Synthesis Without Meta-analysis (SWiM) approach, and certainty of evidence was rated using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) framework. A total of 12 studies with 146 participants in 7 cohorts met the eligibility criteria and were included in the synthesis. Results indicated a wide distribution of reported peaks across many cortical and subcortical regions with mixed directions of activation or perfusion, demonstrating substantial heterogeneity in the reported findings. Risk of bias assessments generally indicated either some concerns or high risk of bias, and the certainty of evidence was judged to be low to very low. Overall, there is a lack of consistent evidence showing the acute effects of CBD on the brain across various study designs. The current literature on the putative anxiolytic effects of CBD is constrained by methodological variability and limited statistical power. Future studies should employ standardized paradigms, improve reporting practices, and include more diverse and adequately powered samples to clarify the neural correlates of CBD-related effects on stress and anxiety.</p><p><strong>Systematic review registration: </strong>PROSPERO, CRD420251063369.</p>","PeriodicalId":73094,"journal":{"name":"Frontiers in neuroimaging","volume":"5 ","pages":"1860919"},"PeriodicalIF":2.5,"publicationDate":"2026-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13391337/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148581534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A rapid streamline-based extension of Tractfinder for white matter tract segmentation.","authors":"Dana Kanel, Fiona Young, Kiran K Seunarine, Chris A Clark, Kristian Aquilina, Jonathan D Clayden","doi":"10.3389/fnimg.2026.1873040","DOIUrl":"10.3389/fnimg.2026.1873040","url":null,"abstract":"<p><p>Accurate delineation of white matter tracts is critical in the pre-operative assessment of paediatric brain tumour patients, where preservation of eloquent pathways directly influences surgical planning and functional outcomes. Tractfinder is a recently introduced automated method for white matter tract segmentation in tumour patients, but its voxel-based (mask) outputs limit compatibility with streamline-based tractography tools, visualisation workflows, and downstream analytical frameworks. Here we introduce Tractfinder-constrained Tractography (TcT), a streamline-based extension that constrains probabilistic tractography to the probability maps produced by Tractfinder, generating streamline representations while preserving the speed and automation that make Tractfinder clinically appealing. We evaluated TcT in ten pre-operative paediatric patients with supratentorial tumours, targeting three clinically relevant tracts - the corticospinal tract, arcuate fasciculus, and optic radiation. Spatial agreement between TcT and conventional tractography was assessed using Bundle Adjacency (BA). Mean BA scores across all three tracts ranged from 2.1 to 2.6 mm, comparing favourably against published inter-protocol benchmarks for conventional probabilistic tractography (4.3 mm), and approaching within-protocol variability. The TcT pipeline was fully automated, required no manual region-of-interest placement, and completed in approximately 5-15 min per subject compared to 1-2 h for conventional tractography. These results demonstrate that TcT produces streamline-based tract segmentations with good spatial agreement to conventional tractography, while offering substantially reduced processing time and operator burden.</p>","PeriodicalId":73094,"journal":{"name":"Frontiers in neuroimaging","volume":"5 ","pages":"1873040"},"PeriodicalIF":2.5,"publicationDate":"2026-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13381243/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148610809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Addressing ethical challenges in the reporting of race and ethnicity population descriptors in human neuroscience research.","authors":"Lauren Lang, Julianna Gerold, Eric Little, Craig McFarland, Beri Tawe, Rishab Kumar Jain, Francis X Shen","doi":"10.3389/fnimg.2026.1744569","DOIUrl":"10.3389/fnimg.2026.1744569","url":null,"abstract":"<p><p>Increased racial and ethnic diversity in population neuroscience research is widely understood to facilitate better identification of subgroup effects and more generalizable findings. Consistency in reporting race and ethnicity population descriptor variables would allow the research community to better assess progress toward more representative datasets. One important lever for ensuring robust and consistent reporting of population descriptors are journal guidelines, and this review of current guidelines finds that there are opportunities for neuroscience journals to strengthen scientific rigor by more clearly delineating expectations with respect to reporting and operationalizing race and ethnicity population descriptors.</p>","PeriodicalId":73094,"journal":{"name":"Frontiers in neuroimaging","volume":"5 ","pages":"1744569"},"PeriodicalIF":2.5,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13388039/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148563939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Differential deficits in pattern- versus flash-visual evoked potentials in schizophrenia: relationship to subcortical visual systems, pulvinar nucleus and cognition.","authors":"Maria B Aburto-Ponce, Kristin Micceri, Antigona Martinez, Daniel C Javitt","doi":"10.3389/fnimg.2026.1833352","DOIUrl":"10.3389/fnimg.2026.1833352","url":null,"abstract":"<p><strong>Background: </strong>The human subcortical visual system is divided into distinct magnocellular, parvocellular and koniocellular pathways, which contribute differentially to specific aspects of early visual processing. Schizophrenia is associated with deficits in early-visual processing, especially involving N-methyl-D-aspartate receptor (NMDAR)-mediated non-linear gain within the subcortical magnocellular visual system. Nevertheless, methods for investigating the pathophysiological consequences remain limited. Flash-VEP can be obtained using either transient (tVEP) or steady-state (ssVEP) approaches. Flash stimuli also induce sustained reduction (\"blocking\") of the posterior alpha rhythm. Red (vs. white) flash stimuli selectively suppress activity in magnocellular-recipient layers of primary visual cortex. Here, we investigated flash-VEP responses in schizophrenia, with emphasis on the potential utility for assessing selective pathophysiological involvement of the magnocellular and koniocellular pathways.</p><p><strong>Methods: </strong>We obtained flash-VEP from 28 healthy control and 27 schizophrenia participants to white and red stimuli across a range of stimulation rates, and pattern-VEP from 29 control and 22 schizophrenia participants. A subset (17 control/15 schizophrenia) participated in both studies. We also obtained fMRI to 6-Hz white and red stimuli in an additional sample of 14 control and 14 schizophrenia participants. fMRI analyses focused on both visual cortex and inferior pulvinar nucleus.</p><p><strong>Results: </strong>Schizophrenia participants showed increased flash-tVEP responses (<i>d</i> = 0.99, <i>p</i> < 0.001) despite significantly reduced pattern-tVEP (<i>d</i> = -0.99, <i>p</i> < 0.001). In addition, the ssVEP (photic driving) response was significantly reduced in schizophrenia, as reflected by reduced intertrial trial coherence (ITC) within the alpha frequency band (<i>d</i> = -0.78, <i>p</i> < 0.001). Alpha blocking was induced equivalently by white and red stimuli in HC, suggesting magnocellular involvement via the retinotectal system. The degree of blocking was significantly reduced in schizophrenia (<i>d</i> = -0.83, <i>p</i> = 0.003) and correlated significantly with neurocognitive impairment (r_p = 0.65, <i>p</i> < 0.001). fMRI studies showed reduced pulvinar activation (<i>d</i> = -1.1, <i>p</i> = 0.008), along with aberrantly increased dorsal cortical activation (<i>d</i> = 0.98, <i>p</i> = 0.019).</p><p><strong>Conclusion: </strong>The findings reinforce the importance of subcortical visual dysfunction as a driver of impaired neurocognition in schizophrenia and provide a scalable mechanism for assessment of early-visual dysfunction within the clinical setting. Deficit patterns are consistent with concepts of impaired magnocellular and koniocellular visual function affecting both thalamocortical and retinotectal system function in schizophrenia.</p>","PeriodicalId":73094,"journal":{"name":"Frontiers in neuroimaging","volume":"5 ","pages":"1833352"},"PeriodicalIF":2.5,"publicationDate":"2026-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13322905/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148378396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Intraoperative contrast-enhanced ultrasound features of progressive multifocal leukoencephalopathy: a case report.","authors":"Lapo Bonosi, Giovanni Tringali","doi":"10.3389/fnimg.2026.1842218","DOIUrl":"10.3389/fnimg.2026.1842218","url":null,"abstract":"<p><p>We report the intraoperative ultrasound findings in a male patient with history of stage IVb mantle cell lymphoma who developed new-onset personality changes and gait instability. Brain imaging revealed an extensive right frontal white matter lesion with subtle multifocal spreading. Given the absence of contrast enhancement on MRI and considering the high-dose steroid therapy administered, an open biopsy was performed due to suspicion of cerebral lymphoma. During procedure, intraoperative ultrasound with and without microbubble contrast was carried out, demonstrating distinct echotexture features, determining the site of biopsy. The histological analysis led to a diagnosis of progressive multifocal leukoencephalopathy (PML). To the best of our knowledge, this may represent one of the first descriptions of intraoperative ultrasound characteristics in PML.</p>","PeriodicalId":73094,"journal":{"name":"Frontiers in neuroimaging","volume":"5 ","pages":"1842218"},"PeriodicalIF":2.5,"publicationDate":"2026-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13222789/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148152372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"SliceMap: a binary classification-driven 2D pipeline for detecting discriminative candidate regions in brain MRI.","authors":"Xiaoye Jiang, Zhijin Wu, Zhaohui S Qin","doi":"10.3389/fnimg.2026.1819355","DOIUrl":"10.3389/fnimg.2026.1819355","url":null,"abstract":"<p><p>Identifying spatially localized neuroanatomical signals from brain magnetic resonance imaging (MRI) is central to many clinical and scientific questions, including medical diagnosis and the investigation of disease mechanisms. However, reliably detecting such subtle and spatially localized signals from high-dimensional MRI data remains challenging. In our study, we propose a performance-guided two-dimensional (2D) slice-based pipeline for identifying candidate spatial regions in brain MRI. The pipeline employs efficient 2D convolutional neural networks trained on plane-specific MRI slices, using binary classification as a modeling task to evaluate slice-level performance. The best-performing slice from each anatomical plane is then subjected to occlusion-based attribution analysis, and the resulting maps are jointly examined to localize a candidate three-dimensional brain region. We demonstrate the proposed pipeline using sex classification as a controlled testbed, identifying a spatially localized candidate region corresponding to the anterior cingulate cortex and adjacent medial structures including portions of the corpus callosum genu, consistent with prior neuroanatomical findings on sex differences in these regions.</p>","PeriodicalId":73094,"journal":{"name":"Frontiers in neuroimaging","volume":"5 ","pages":"1819355"},"PeriodicalIF":2.5,"publicationDate":"2026-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13218861/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148139909","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pulvinar pathways as skip connections in deep neural networks for vision.","authors":"Narmin Zarinabadi, Christian Casanova, Nelson Cortes","doi":"10.3389/fnimg.2026.1800369","DOIUrl":"10.3389/fnimg.2026.1800369","url":null,"abstract":"<p><strong>Introduction: </strong>The pulvinar is thought to regulate cortico-cortical communication through transthalamic pathways, yet the computational consequences of such modulation remain unclear.</p><p><strong>Methods: </strong>A minimal pulvinar-inspired long-range skip pathway in a hierarchical convolutional vision model was tested, implemented as a learned projection from early to late feature maps coupled with a gain-controlled gating mechanism. The architecture was evaluated in two complementary experiments: CIFAR-10 categorization and a near-threshold contrast-detection task with noisy backgrounds.</p><p><strong>Results: </strong>In CIFAR-10 categorization, the pulvinar-augmented model did not primarily act as a uniform accuracy booster; instead, it reshaped contrast-dependent response scaling and stabilized internal representations, consistent with gain control. These effects persisted under matched representational regimes, indicating that performance differences cannot be explained by changes in representational geometry alone. In the near-threshold detection task, pulvinar-like modulation systematically redistributed detection outcomes, consistent with shifts in decision criterion under uncertainty, and in specific regimes supported improved discriminability.</p><p><strong>Discussion: </strong>Together, these findings indicate that pulvinar-inspired connectivity contributes primarily to gain and decision-criterion control. We propose that the pulvinar regulates how sensory evidence is weighted and converted into decisions, rather than directly enhancing task accuracy.</p>","PeriodicalId":73094,"journal":{"name":"Frontiers in neuroimaging","volume":"5 ","pages":"1800369"},"PeriodicalIF":2.5,"publicationDate":"2026-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13215803/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148139933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}