Biology subjects

Osorio, S.

Publications and source records attributed to Osorio, S..

12 recordsLinked to original sources

bioRxiv2026

MEG Signatures of Differences in Auditory Cortex Responses to Trigger versus Non-Trigger Sounds in Misophonia

Misophonia is characterized by intense emotional and physiological reactions to specific trigger sounds that may vary across individuals. Despite greater recognition and increased research, the neural mechanisms underlying misophonia are still poorly understood. Using magnetoencephalography (MEG) with millisecond temporal resolution, we examined auditory cortex responses to trigger versus non-trigger sounds in 23 individuals (ages 14 - 32 years) that met criteria for misophonia on a screening assessment. We found that in the right hemisphere, trigger sounds elicited significantly smaller evoked responses, lower power of evoked alpha-band oscillations, and stronger alpha-gamma cross-frequency phase-amplitude coupling, compared to non-trigger sounds. We also found that evoked responses and power correlated with behaviorally assessed extent of misophonia symptoms. These findings support the idea that misophonia is characterized at least in part by altered neurophysiological processing of auditory trigger stimuli early in auditory cortex hierarchy. Our results provide novel insight into the neural basis of misophonia, and underscore the importance of examining brain activity even at the earliest levels of the cortical hierarchy, especially with high spatio-temporal resolution.

neuroscience↗

bioRxiv2026

Cortical Excitation-Inhibition Balance in Autism Varies by Brain Region and Age

Autism spectrum disorder (ASD) is characterized by differences in social communication, interaction, and restricted and repetitive behaviors. The hypothesis that ASD involves altered cortical excitation-inhibition (EI) balance has been extensively investigated, yet evidence remains mixed, partly because EI balance changes substantially during typical maturation. We used resting-state magnetoencephalography (MEG) to examine developmental trajectories of cortical EI alterations with regional specificity in a large cross-sectional cohort (N = 172; 92 typically developing, 80 ASD; ages 6-32). Functional EI (fEI), derived from critical brain dynamics, was estimated across 500 cortical parcellations. Group-averaged fEI maps revealed broadly similar large-scale topographic patterns across groups. Age-stratified analyses revealed increased global fEI in childhood and decreased fEI in adolescence in ASD, with no evidence of a group difference in adulthood. Parcel-wise regressions identified a significant main effect of diagnosis in right dorsolateral prefrontal cortex, where typically developing individuals showed higher fEI across all ages. A significant group-by-age interaction in left inferior parietal cortex indicated diverging developmental trajectories. Finally, fEI in paracentral and precuneus regions was associated with the magnitude of ASD symptoms. These findings indicate that EI imbalance in ASD is neither globally distributed nor static, but expressed through regionally and developmentally specific differences, with relevance for ASD heterogeneity.

neuroscience↗

bioRxiv2026

Context-dependent selection and genetic facilitation and constraint on rosette diameter and herbivore resistance across european outdoor common gardens under ambient and reduced precipitation in Fragaria vesca

The expression of plant defensive traits against herbivores often incurs costs to other essential functions, such as growth and reproduction. Understanding how selection acts on putatively functional traits that are expected to trade off across space and time is therefore critical for predicting evolutionary responses to ongoing and future environmental change. Here, we used multiple replicated genotypes of woodland strawberry (Fragaria vesca; Rosaceae) grown over two years in three outdoor common gardens in Spain, Belgium, and Sweden. In each garden, genotypes were exposed to both a reduced-precipitation treatment simulating drought and an ambient precipitation treatment. We estimated directional and correlational selection on rosette diameter (a proxy for growth) and herbivore resistance (measured as the inverse of chewing damage) using fruit and stolon production as proxies for sexual and asexual fitness across all environments (i.e., every site x year x treatment combination). We then combined selection gradients with environment-specific genetic (co)variance among genotypes to quantify the expected response to selection ({Delta}z = G{beta}) and to identify covariance-driven constraints or facilitation therein. Selection consistently favored larger rosette diameter for both fitness proxies across nearly all environments, which, in combination with genetic covariances among genotypes, resulted in a general evolutionary response toward increased rosette diameter, with the strongest response at the wettest site (Belgium). In contrast, selection on resistance and the corresponding among-genotype evolutionary responses were strongly context-dependent. Correlational selection on rosette diameter x resistance occurred in only a few environments, primarily under reduced precipitation. Environment-dependent genetic covariances constrained or facilitated selection on both traits only at the site with the highest herbivory (Sweden) under drought conditions. Overall, our results reveal a context-dependent interplay between selection and genetic architecture, underlining the difficulty of predicting evolutionary trajectories under environmental change, and highlighting how spatially and temporally variable conditions may maintain standing genetic variation in plant traits.

evolutionary biology↗

bioRxiv2025

Variation in phenotypic plasticity of metabolic and performance traits along a latitudinal gradient in Woodland Strawberry

Phenotypic plasticity and local adaptation jointly determine plant responses to environmental variation, yet their relative contributions and evolutionary interactions remain poorly understood. We grew fifteen woodland strawberry (Fragaria vesca) genotypes from a European latitudinal gradient in four common gardens for two years, quantifying primary metabolites and biomass, reproduction and herbivore damage-related traits. Considering all measured traits combined, environment explained the largest variance (30%), followed by genotype-by-environment interactions (18%) and genotype effects (9%), indicating substantial heritable plasticity. However, plasticity was not uniform: northern genotypes showed greater plasticity in stress metabolites like succinic acid but more canalized growth traits, whereas southern genotypes maintained constitutively high protective metabolite levels. Latitude explained 4.4% of plasticity profile variation. Phenotypic variation was consistently better explained by long-term temperature than precipitation at the site of origin across all trait groups under study. Our results indicate that plasticity itself is an evolved, trait-specific characteristic shaped by climatic gradients, challenging simple hierarchies of trait lability. Significance StatementWe studied wild strawberries from across Europe and discovered that populations from different regions have evolved distinct adaptive strategies to cope with their local cli-mates. These differences highlight the remarkable diversity of plant solutions to environmental challenges. Understanding these natural adaptations could help us breed strawberries or other plant organisms better suited to future climate conditions.

ecology↗

bioRxiv2025

High-Capacity transcranial Direct Current Stimulation (HC-tDCS)

BackgroundEnhancing tDCS technology can support the delivery of higher current intensities, enabling broader dose-response studies in human trials. MethodsHigh-Capacity tDCS (HC-tDCS) integrates novel electrodes and adaptive current/voltage controlled electronics. Multi-layer HC electrodes include polarity-specific redox layers and designed hydrogel interfaces, shaped for a bifrontotemporal montage. The stimulator design includes adaptive ramps with hybrid voltage-current control and low (7.5 V) compliance voltage. Scanning electron microscopy (SEM) and electrical impedance spectroscopy (EIS) were used to characterize electrode properties. Tolerability of HD-tDCS was tested for target currents 1-6 mA (in 1 mA increments) for 30 min on 5 healthy subjects, and compared with conventional tDCS using 2 mA F3-F4 sponge-electrodes. MRI-derived computational models predicted cortical electric fields. Tolerability was assessed according to the 100 mm visual analogue scale for pain (VASP-100), skin erythema assessment, thermal imaging, and adverse event questionnaires. ResultsThe electrode design including high-roughness polarity-specific capacity, electrochemically supports high-charge direct current stimulation. In all subjects, HC-tDCS was well tolerated at all tested doses (1-6 mA) with minor transient adverse events and average VASP-100 less than 15. VASP-100 during sponge-electrode tDCS at 2 mA was comparable to 5 and 6 mA HC-tDCS. HC-tDCS operates at significantly lower voltage than sponge-tDCS, impacting tolerability and efficiency. Modeling predicts peak frontal electric fields of 0.65-1.08 V/m for 2 mA HC-tDCS and 1.95-3.25 V/m for 6 mA HC-tDCS, compared to 0.49-0.95 V/m for 2 mA sponge-tDCS. ConclusionsHC-tDCS allows increased cortical stimulation; at 6 mA achieving double the 1 V/m electric field threshold in all subjects. Enabled by pre-stimulation procedures, specialized electrodes, and adaptive low-voltage stimulators, HC-tDCS is well tolerated at intensities up to at least 6 mA.

bioengineering↗

bioRxiv2025

Molecular mechanisms underlying the early steps of floral initiation in seasonal flowering genotypes of cultivated strawberry

Floral initiation is required for sexual reproduction in angiosperm plants, and has a significant impact on crop yields. In cultivated strawberry, the molecular basis of floral initiation is poorly understood and most studies have focused on a single genotype grown under controlled conditions. To gain more insight into this process, we conducted a study under natural conditions in two countries using two seasonal flowering cultivars. We focused on the early steps of floral initiation by using samples spanning key developmental stages of the shoot apical meristem. The analysis of differential gene expression in leaf and terminal bud tissues revealed enrichment for genes involved in carbohydrate metabolism and phytohormone pathways in leaves. Other protein classes that were enriched during early floral initiation were associated with cytoskeleton organization, cell cycle regulation, and chromatin structure. We also identified genes associated with the photoperiodic pathway, well-characterized floral integrators such as TFL1 and SOC1, and several linked to phytohormone regulation, such as XTH23, PP2 and EIN3.

plant biology↗

bioRxiv2025

Decreased auditory cortical activations and altered long-range alpha-band connectivity characterize passive auditory spatial attention in ASD

Autism Spectrum Disorder (ASD) is a developmental condition characterized by difficulties in social interaction, communication and sensory processing. The ability to orient towards sounds is a key component of social interactions, yet auditory spatial attention remains relatively understudied in ASD, despite prior research indicating differences in this domain. Here, we investigate the neural signatures associated with passive auditory spatial attention in children with ASD (n = 21, ages 6-17) relative to age- and IQ-matched typically developing (TD) children (n = 31), using source-localized magnetoencephalography (MEG). Participants listened passively, while watching a silenced movie, to non-social auditory stimuli designed to either remain lateralized to one hemifield (stay trials), or to change in location from one side to the contralateral hemifield (jump trials). Linear mixed effects modeling showed lower cortical activation in the auditory cortex in the ASD group in response to jump trials, relative to the TD group. Additionally, functional connectivity analyses showed higher alpha-band functional connectivity in the ASD group between left auditory cortex seeds and right prefrontal and left parietal regions known to be recruited during auditory spatial attention. Right prefrontal alpha-band connectivity estimates were associated with behaviorally assessed auditory processing scores, whereas left parietal connectivity estimates were associated with ASD symptomatology. Our results align with the hypothesis that auditory spatial attention generally, and specifically orientation to sounds even when experienced passively, differs in ASD individuals.

neuroscience↗

bioRxiv2024

DeepMapper: Attention-Based AutoEncoder for System Identification in Wound Healing and Stage Prediction

Advancements in bioelectronic sensors and actuators have paved the way for real-time monitoring and control of wound healing progression. Real-time monitoring allows for precise adjustment in treatment strategies that align with an individuals unique biological response. However, due to the complexities of human-drug interactions and a lack of predictive models it is challenging to determine just how one should adjust drug dosage to achieve the desired biological response. This work proposes an adaptive closed-loop control framework that integrates deep learning, optimal control, and reinforcement learning to update treatment strategies in real-time with the goal of accelerating wound closure. The proposed approach eliminates the need for mathematical modeling of complex nonlinear wound healing dynamics. We demonstrate the convergence of the controller via an in silico experimental setup, where the proposed approach successfully accelerates the wound healing process by 17.71%. Finally, we share the experimental setup and results of an in vivo implementation to highlight the translational potential of our work. Our data-driven model estimates a 40% acceleration in wound closure.

systems biology↗

bioRxiv2024

Cortical tracking of naturalistic music and speech across frequency bands and brain regions: functional mapping and temporal dynamics

Music and speech encode hierarchically organized structural complexity at the service of human expressiveness and communication. Previous research has shown that populations of neurons in auditory regions track the envelope of acoustic signals within the range of slow and fast oscillatory activity. However, the extent to which cortical tracking is influenced by the interplay between stimulus type, frequency band, and brain anatomy remains an open question. In this study, we reanalyzed intracranial recordings from thirty subjects implanted with electrocorticography (ECoG) grids in the left cerebral hemisphere, drawn from an existing open-access ECoG database. Participants passively watched a movie where visual scenes were accompanied by either music or speech stimuli. Cross-correlation between brain activity and the envelope of music and speech signals, along with density-based clustering analyses and linear mixed effect modeling, revealed both anatomically overlapping and functionally distinct mapping of the tracking effect as a function of stimulus type and frequency band. We observed widespread left-hemisphere tracking of music and speech signals in the Slow Frequency Band (SFB, band-passed filtered low-frequency signal between 1-8Hz), with near zero temporal lags. In contrast, cortical tracking in the High Frequency Band (HFB, envelope of the 70-120Hz band-passed filtered signal) was higher during speech perception, was more densely concentrated in classical language processing areas, and showed a frontal-to-temporal gradient in lag values that was not observed during perception of musical stimuli. Our results highlight a complex interaction between cortical region and frequency band that shapes temporal dynamics during processing of naturalistic music and speech signals.

neuroscience↗

bioRxiv2020

Pupil-linked arousal is sensitive to subconscious processing of auditory novelty

Detection of novel stimuli that violate statistical regularities in the sensory scene is of paramount importance for the survival of biological organisms. Event-related potentials, phasic increases in pupil size, and evoked changes in oscillatory power in the theta (4-8 Hz) frequency range have been proposed as markers of sensory novelty detection. However, how conscious access to novelty modulates these different brain responses is not well understood. Here, we studied the neural responses to sensory novelty in the auditory modality with and without conscious access. We identified individual thresholds for conscious auditory discrimination and presented to our participants sequences of tones, where the last stimulus could be another standard, a subthreshold target or a suprathreshold target. Participants were instructed to report whether the last tone of each sequence was the same or different from those preceding it. Results indicate that stimulus evaluation and overt decision-making mechanisms, indexed by the P3 event-related response and reaction times, best predict whether a novel stimulus will be consciously accessed or not. In contrast, increased pupil size does not predict conscious access to novelty but reflects unexpected sensory uncertainty. These results highlight the interplay between bottom-up and top-down mechanisms and how the brain weights neural responses to novelty and uncertainty during perception and goal-directed behavior.

neuroscience↗

bioRxiv2020

Allelic Variation of MYB10 is the Major Force Controlling Natural Variation of Skin and Flesh Color in Strawberry (Fragaria spp.) fruit

Anthocyanins are the principal color-producing compounds synthesized in developing fruits of strawberry (Fragaria spp.). Substantial natural variation in color have been observed in fruits of diploid and octoploid accessions, resulting from distinct accumulation and distribution of anthocyanins in fruits. Anthocyanin biosynthesis is controlled by a clade of R2R3 MYB transcription factors, among which MYB10 has been shown as the main activator in strawberry fruit. Here, we show that MYB10 mutations cause most of the anthocyanin variation observed in diploid woodland strawberry (F. vesca) and octoploid cultivated strawberry (F. xananassa). Using a mapping-by-sequencing approach, we identified a gypsy-transposon insertion in MYB10 that truncates the protein and knocks out anthocyanin biosynthesis in a white-fruited F. vesca ecotype. Two additional loss-of-function MYB10 mutations were identified among geographically diverse white-fruited F. vesca ecotypes. Genetic and transcriptomic analyses in octoploid Fragaria spp. revealed that FaMYB10-2, one of three MYB10 homoeologs identified, residing in the F. iinumae-derived subgenome, regulates the biosynthesis of anthocyanins in developing fruit. Furthermore, independent mutations in MYB10-2 are the underlying cause of natural variation in fruit skin and flesh color in octoploid strawberry. We identified a CACTA-like transposon (FaEnSpm-2) insertion in the MYB10-2 promoter of red-fleshed accessions that was associated with enhanced expression and anthocyanin accumulation. Our findings suggest that putative cis regulatory elements provided by FaEnSpm-2 are required for high and ectopic MYB10-2 expression and induction of anthocyanin biosynthesis in fruit flesh. We developed MYB10-2 (sub-genome) specific DNA markers for marker-assisted selection that accurately predicted anthocyanin phenotypes in octoploid segregating populations.

plant biology↗

bioRxiv2018

Vascular brassinosteroid receptors confer drought resistance without penalizing plant growth

Drought represents a major threat to food security. Mechanistic data describing plant responses to drought have been studied extensively and genes conferring drought resistance have been introduced into crop plants. However, plants with enhanced drought resistance usually display lower growth, highlighting the need for strategies to uncouple drought resistance from growth. Here, we show that overexpression of BRL3, a vascular-enriched member of the brassinosteroid receptor family, can confer drought stress tolerance in Arabidopsis. Whereas loss-of-function mutations in the ubiquitously expressed BRI1 receptor leads to drought resistance at the expense of growth, overexpression of BRL3 receptor confers drought tolerance without penalizing overall growth. Systematic analyses reveal that upon drought stress, increased BRL3 triggers the accumulation of osmoprotectant metabolites including proline and sugars. Transcriptomic analysis suggests that this results from differential expression of genes in the vascular tissues. Altogether, this data suggests that manipulating BRL3 expression could be used to engineer drought tolerant crops.

plant biology↗