http://hdl.handle.net/10366/4616 2026-06-05T05:02:46Z 2026-06-05T05:02:46Z Cacciato Salcedo, Sara Jaokar, Shreya Ingham, Neil J. Malmierca, Manuel S. Petrinovic, Marija M. http://hdl.handle.net/10366/171673 2026-06-02T00:02:37Z 2026-05-17T00:00:00Z

Auditory mismatch responses—mismatch negativity (MMN) and mismatch fields (MMF)—are well established electrophys-iological markers of automatic auditory discrimination supported by short-term sensory memory. These responses, typicallyelicited using passive oddball paradigms, are increasingly used to investigate sensory and language processing in autism. Thissystematic review synthesizes findings from 55 studies comparing MMN and MMF responses in autistic and typically developing(TD) individuals across childhood, adolescence, and adulthood. Using the Synthesis Without Meta-analysis (SWiM) framework,we identified consistent evidence for smaller MMN amplitudes and reduced MMF power in autistic children and adolescentsrelative to TD peers, particularly in response to frequency, duration, and speech-based deviants. Studies also frequently reportedlonger mismatch latencies in autistic participants and associated these delays with language difficulties and heightened auditorysensitivity. Although some studies reported age-related convergence in MMN and MMF measures between autistic and TDgroups in later childhood or adolescence, greater right-hemisphere lateralization in autistic individuals emerged as a consistentfinding across both speech and non-speech paradigms, suggesting differences in hemispheric weighting for auditory process-ing of linguistic and non-linguistic cues. To explain interindividual and developmental variability in mismatch responses, wepropose a precision-weighted predictive coding account, in which divergent assignment of confidence to sensory predictionerrors may contribute to autism-related differences. While study quality was generally fair, methodological heterogeneity, un-derrepresentation of females, and limited cross-cultural sampling constrain generalizability. Future research should prioritizelongitudinal, sex-stratified, and culturally diverse designs, using standardized protocols and collaborative data practices. MMNand MMF responses hold promise as non-invasive translational biomarkers of early-stage sensory prediction and neurodevelop-mental variation in autism

2026-05-17T00:00:00Z Cacciato Salcedo, Sara Lao Rodríguez, Ana Belén Malmierca, Manuel S. http://hdl.handle.net/10366/171672 2026-06-02T00:02:08Z 2026-05-10T00:00:00Z

[EN] In autism, sensory differences have been linked to altered contextual processing and to how temporal structure supports the formation of regularities and predictions. Here, we examined how temporal and contextual auditory processing are shaped by sex, development, and prenatal valproic acid (VPA) exposure in the non-lemniscal inferior colliculus at low sound levels. Single-unit recordings from control and VPA-exposed rats were obtained using oddball and cascade paradigms, allowing dissociation of mismatch (iMM), repetition suppression (iRS), and prediction-error (iPE) components in both response magnitude and latency.In control animals, maturation selectively reorganized contextual and predictive processing in females, shifting responses toward reduced repetition suppression and increased prediction-error signaling. This shift was accompanied by longer response latencies, indicating a broader temporal integration window. Compared to male rats, adult females displayed prediction-driven, with reduced adaptation bias, of mismatch responses.In contrast, prenatal VPA exposure disrupted this sex- and age-dependent pattern, particularly in females, producing reduced response magnitude together with earlier response peaks. These findings reveal a female-specific reorganization of subcortical contextual processing and demonstrate that sex, age, and prenatal VPA exposure-related effects can dissociate response strength from temporal deployment. Collectively, our results highlight the role of temporal dynamics in contextual computation within the auditory midbrain and support the contribution of early subcortical circuits to autism-related sensory processing

2026-05-10T00:00:00Z Varela Andrés, Natalia Hernández del Caño, Carlos Cebrián León, Alejandro Blanco de la Iglesia, Adrián Los Arcos-López de Pariza, Izaskun Santos Fernández del Campo, Inés García Losada, Sandra Arévalo Martín, Juan Carlos Sánchez Martín, Manuel Adolfo Bajo Grañeras, Raquel Martín, Ricardo Sánchez Aguilera, Alberto Merchán, Miguel.A. Deogracias, Rubén http://hdl.handle.net/10366/171671 2026-06-02T00:01:56Z 2026-05-18T00:00:00Z

Brain-derived neurotrophic factor (BDNF) is a master regulator of neuronal differentiation and inhibitory circuit maturation in the mammalian brain. Yet, its downstream mediators in distinct neuronal populations remain incompletely defined. Here, we identify mitogen- and stress-activated kinase 1 (MSK1) as a critical mediator of BDNF signalling during postnatal striatal development. MSK1 expression predominates in GABAergic neurons across the cortex and striatum, with region-specific dynamics: MSK1 expression in cortical GABAergic interneurons declines from postnatal day 5 (P5) to day 30 (P30), while expression in striatal GABAergic medium spiny neurons (MSNs) persists into adulthood. Using a novel Msk1IV KO mouse model, generated by deleting exon IV of Msk1, we find that striatal volume and MSN dendritic complexity decrease by P60, without cortical neuron alterations, underscoring MSK1´s striatal-specific role. Mechanistically, MSK1 drives BDNF-induced MeCP2 phosphorylation at serine 421 in MSNs via MAPK/ERK, independently of CaMKII, forming a nuclear complex with MeCP2, thus amplifying MSK1´s role in transcriptional regulation. This MSK1-MeCP2 signalling is also involved in BDNF-dependent and independent morphological developmental processes of cultured striatal neurons. Accordingly, Msk1IV KO striatum shows dysregulated GABAergic (Gad1, Gabrg3) and dopaminergic (Drd1, Drd2, Drd3) gene expression, mirroring profiles in MeCP2 deficient models. Behaviourally, Msk1IV KO mice display hypersociability, impaired nest-building, and increased depressive-like behaviour in the forced swimming test, contributing to striatal circuit dysfunction. These findings link MSK1-mediated molecular disruptions to inhibitory circuit imbalances and behaviours reminiscent of psychiatric disorders, positioning MSK1 as a potential therapeutic target for neurodevelopmental and psychiatric disorders, including those associated with MeCP2 dysfunction.

2026-05-18T00:00:00Z Fernández del Campo, Inés S. Cebrián León, Alejandro Hernández del Caño, Carlos Varela Andrés, Natalia Plaza Gutiérrez, Juan Ignacio Deogracias, Rubén Merchán Cifuentes, Miguel Ángel http://hdl.handle.net/10366/170947 2026-04-14T00:01:21Z 2026-02-19T00:00:00Z

[EN]Age-related hearing loss (ARHL) disrupts ascending auditory inputs, impairing auditory signal transmission, triggering cortical hyperexcitability, and increasing the risk of age-related cognitive decline. In early aging, multisession epidural direct current stimulation (DCS) of the auditory cortex (AC) preserves auditory thresholds and prevents cortical hyperexcitability in Wistar rats. Here, we hypothesized that multisession DCS could halt transcriptional dysregulation in the AC at the earliest stages of aging. We have characterized age-related transcriptional changes in the AC to assess DCS-mediated effects by RNA-seq. At 18.13 months, non-stimulated, aged rats (NES) showed 194 differentially expressed genes (DEGs) in relation to young controls (YG), with enrichment in pathways associated with GABAergic, glutamatergic, and dopaminergic synapses, long-term potentiation/depression, inflammaging, autophagy, apoptosis and neurodegeneration. The upregulated genes included Gabrb1, Grin2b, Rac3c, Tnr, and Ndst1, suggesting compensatory hyperactivity, excitatory/inhibitory imbalance, and stiffening of perineuronal nets (PNN) around parvalbumin (PV) interneurons. Electrically stimulated (ES) rats showed 86 DEGs in relation to YG, with no significant enrichment in aging-related pathways. By contrast, NES vs ES showed 1393 DEGs, with strong enrichment in aging-related pathways. Also, many of the 121 common DEGs across comparisons, which are upregulated in NES and downregulated in ES, are related to neurotransmission (Gabrb1, Grin2b), synaptic scaffolding (Dlg2, Prkca), trophic signaling (Ntrk2, Igf1r) and PNN (Tnr, Ndst1). Based on these findings, multisession DCS curbs maladaptive genomic reprogramming in the aged AC most likely by preserving excitatory/inhibitory balance and maintaining PNN integrity, thereby protecting the AC from ARHL and cognitive vulnerability.

2026-02-19T00:00:00Z Cacciato Salcedo, Sara Lao Rodríguez, Ana Belén Malmierca, Manuel S. http://hdl.handle.net/10366/170888 2026-04-09T00:01:03Z 2026-01-30T00:00:00Z

[EN] Atypical sensory processing is a common feature of autism, yet the neural computations that give rise to these differences, particularly in relation to biological sex and etiological origin, remain unclear. Here we examine predictive auditory processing at the single-neuron level in the inferior colliculus of two adult rat models of autism: a genetic model with a heterozygous Grin2b deletion (Grin2b + /-) and an environmental model based on prenatal valproic acid exposure. We recorded neuronal responses to an auditory oddball paradigm and a cascade control sequence across lemniscal and non-lemniscal IC divisions under high-intensity stimulation, allowing us to derive indices of repetition suppression, prediction error and neuronal mismatch. Using generalized linear mixed-effects models that accounted for animal identity, inferior colliculus division, sex, and rat model, followed by hierarchical group-level comparisons, we identified robust alterations in predictive processing in both autism-like models. These effects varied across inferior colliculus divisions and differed between sexes, revealing distinct phenotype-specific signatures. The results indicate that sex and etiology jointly modulate early auditory computations in autism. More broadly, our findings highlight the translational value of predictive coding frameworks and support the use of complementary animal models to capture neurobiological heterogeneity across the autism spectrum

2026-01-30T00:00:00Z Vázquez-Borsetti, Pablo Lao Rodríguez, Ana Belén Malmierca, Manuel S. Pérez González, David http://hdl.handle.net/10366/169921 2026-02-20T01:02:44Z 2026-01-10T00:00:00Z

[EN]This work presents three open datasets featuring various levels of processing, containing neural recordings from the auditory cortex of rats. These recordings were obtained during experiments using the auditory oddball paradigm before, during and after the local microiontophoretic application of acetylcholine. The primary objective of these datasets is to investigate how the brain processes predictable versus unexpected auditory stimuli, and the role of cholinergic inputs during such processing. The data include multi-unit recordings of neuronal activity during the presentation of standard and deviant tones, classified by stimulus type and cortical sub-region. These resources enable quantitative investigations of deviance detection, stimulus-specific adaptation, cholinergic modulation and predictive-coding mechanisms at multiple temporal scales.

2026-01-10T00:00:00Z Afonso, Gonçalo José Martins Cavaleiro, Carla Nunes, Sofia Marlene Pereira, Francisco Oliveira, Paulo Jorge Valero , Jorge Mota, Sandra Isabel Ferreiro, Elisabete http://hdl.handle.net/10366/169672 2026-02-11T01:00:37Z 2026-01-26T00:00:00Z

[EN] Background: Urine-derived stem cells (UDSC) are an emerging, non-invasive source of human stem cells combining easy collection, broad accessibility and high patient compliance with multilineage differentiation capacity. However, key gaps remain in UDSC research, particularly in understanding sex-related differences and the lack of a validated cryopreservation protocol, a critical aspect for primary cells, given their variability in colony formation, proliferation rates and experimental timing. To address these limitations, this study aimed to establish, for the first time, a reliable protocol for UDSC cryopreservation and to explore potential sex-related differences, with a specific focus on glycolysis and mitochondrial respiration. Methods: UDSC were isolated from urine samples of healthy donors (aged 27–50, 4 males and 4 females), cultured in 1:1 DMEM:KSFM supplemented with 10% fetal bovine serum and cryopreserved at passages 2–4 using the same medium with the sole addition of 5% dimethyl sulfoxide. Cells were evaluated for viability, apoptosis/necrosis, metabolic profile and multilineage differentiation potential. Comparisons were performed based on donor sex, as well as before and after cryopreservation. Results: Male- and female-derived UDSC displayed no significant differences in viability and cell death or metabolic profile. Moreover, supervised and unsupervised machine learning methods were unable to discriminate between the two groups, allowing for pooled data analysis and improved statistical power. Similarly, fresh and cryopreserved UDSC displayed comparable viability, metabolic activity and multilineage differentiation relative to fresh cells, with no detectable differences in computational analyses. Conclusions: These findings support UDSC adoption for biobanking, disease modelling and regenerative medicine.

2026-01-26T00:00:00Z Sánchez Sánchez, Jazmín Pérez González, David Malmierca, Manuel S. http://hdl.handle.net/10366/169493 2026-02-05T01:01:01Z 2025-12-24T00:00:00Z

[EN] The hippocampus is classically linked to memory, yet increasing evidence points to a broader role in perceptual inference and deviance detection. Predictive coding theories propose that perception minimizes mismatches between expected and actual sensory input, expressed in neural signatures such as mismatch negativity (MMN) and P300. Although MMN arises mainly from sensory and prefrontal cortices, the hippocampus is anatomically interconnected with both and may also contribute to prediction error processing. We recorded single- and multi-unit activity and local field potentials (LFPs) from DG and CA1 in urethane-anesthetized rats during an auditory oddball paradigm and a no-repetition control sequence to dissociate prediction error from repetition suppression. Approximately 20% of hippocampal neurons were sound responsive, and a subset showed deviant selectivity. Spiking activity predominantly reflected prediction errors, while LFPs revealed complementary contributions from repetition suppression and prediction error. Early LFP components were enhanced for randomly presented deviants, whereas later components within the P300 latency range were stronger for predictable deviants, indicating temporally distinct phases of error signaling and top-down modulation. These findings identify the hippocampus as an active contributor to auditory deviance detection and support a hierarchical model in which hippocampal circuits participate in predictive sensory processing beyond memory.

2025-12-24T00:00:00Z Cerveró García, Pilar Jiménez Madrona, Enrique Álvarez Vázquez, Andrea Flores Hernández, Raquel García Vicente, Laura García Guerrero, Laura Alonso Amador, Juan José González Sánchez, Raúl Ollauri Ibáñez, Claudia Paniagua Sancho, María Talaverón Aguilocho, Rocío Rodrigues Teixeira, Telmo Martín Guerrero, Sandra M. Casado, Pedro Rajeeve, Vinothini Shields, Tommy Hijazi Vega, Maruan Cutillas, Pedro R Jaraíz Rodríguez, Myriam Tabernero Urbieta, María Aránzazu http://hdl.handle.net/10366/169127 2026-03-25T12:20:01Z 2026-01-01T00:00:00Z

[EN] Background: TAT-Cx43266-283 is a novel Src inhibitor, which has shown noteworthy antitumor effects in preclinical models of glioblastoma. Because Src plays a pivotal role in several tumor types, including lung cancer brain metastasis derived from non-small cell lung cancer (NSCLC) cells, we investigated the effect of TAT-Cx43266-283 in NSCLC-derived brain metastasis, a disease of unmet clinical need. Methods: The effect of TAT-Cx43266-283 was studied in Lewis Lung Carcinoma (LLC), LSZ4, A549 and H441 NSCLC cells. The non-adherent stem-like LLC cells (LLC-CSCs) were intracranially implanted in immunocompetent mice to study the effect of TAT-Cx43266-283 in vivo. Phosphoproteomic analysis was employed to identify signaling pathways affected by TATCx43266-283, and the most prominent were validated by Western blot and immunohistochemistry. Datasets of human NSCLC adenocarcinoma were also analyzed. Results: TAT-Cx43266-283 significantly reduced LLC-CSCs viability and increased the survival of mice bearing brain tumors derived from these cells. Phosphoproteomic analysis identified MEK and ERK as key effectors of this treatment. TAT-Cx43266-283 induced apoptosis, impaired cytoskeletal dynamics and disrupted tumor vascularization. Patient datasets revealed that the targets of TAT-Cx43266-283 were significantly enriched in KRAS-altered lung tumors. Functional validation in several human and mouse KRAS-mutated non-adherent NSCLC cells confirmed that TAT-Cx43266-283 reduced their growth and invasiveness. Conclusions: Our results suggest that TAT-Cx43266-283 is a promising antitumor drug for lung cancer brain metastasis, as judged by the dual inhibition of Src and the MEK-ERK pathway in KRAS-mutated NSCLC. This study opens new avenues for exploring TAT-Cx43266-283 in other tumor types driven by these molecular alterations.

2026-01-01T00:00:00Z Martín Rodríguez, Carlos Song, Minseok Anta, Begoña González Calvo, Francisco J. Deogracias, Rubén Jing, Deqiang Lee, Francis S. Arévalo Martín, Juan Carlos http://hdl.handle.net/10366/169126 2026-01-22T01:01:55Z 2020-12-23T00:00:00Z

[EN] Ubiquitylation of receptor tyrosine kinases (RTKs) regulates both the levels and functions of these receptors. The neurotrophin receptor TrkB (also known as NTRK2), a RTK, is ubiquitylated upon activation by brain-derived neurotrophic factor (BDNF) binding. Although TrkB ubiquitylation has been demonstrated, there is a lack of knowledge regarding the precise repertoire of proteins that regulates TrkB ubiquitylation. Here, we provide mechanistic evidence indicating that ubiquitin carboxyl-terminal hydrolase 8 (USP8) modulates BDNF- and TrkB-dependent neuronal differentiation. USP8 binds to the C-terminus of TrkB using its microtubule-interacting domain (MIT). Immunopurified USP8 deubiquitylates TrkB in vitro, whereas knockdown of USP8 results in enhanced ubiquitylation of TrkB upon BDNF treatment in neurons. As a consequence of USP8 depletion, TrkB levels and its activation are reduced. Moreover, USP8 protein regulates the differentiation and correct BDNF-dependent dendritic formation of hippocampal neurons in vitro and in vivo. We conclude that USP8 positively regulates the levels and activation of TrkB, modulating BDNF-dependent neuronal differentiation.

2020-12-23T00:00:00Z Moradi Chekan, Ahmad Mesri Gundoshmian, Tarahom Latifi Amoghin, Meysam Shahgholi, Gholamhossein Shirzad Iraj, Mohammad Arribas, Juan Ignacio http://hdl.handle.net/10366/168924 2026-01-17T01:00:40Z 2026-01-01T00:00:00Z

[EN] Aflatoxins are toxic and carcinogenic mycotoxins posing a significant threat to human health and food safety. A non-destructive hyperspectral imaging (HSI) system to automatically detect aflatoxin contamination in olive fruit and powder by machine learning was proposed. Imaging was conducted in the 418–1072 nm wavelength range. For whole fruit analysis, Linear Discriminant Analysis (LDA) achieved 100 % accuracy in binary classifying healthy and contaminated samples. The Support Vector Machine method also reached 98.75 % accuracy for the same purpose. For powdered olive samples, PLSR based on full spectral data, yielded coefficient of determination (R2) values of 0.9986 and 0.9858, for calibration and validation disjoint data sets, respectively. Furthermore, combining Decision Tree with a Learning Automata algorithm extracted the 15 optimal most discriminant (effective) wavelength (EW) values, enabling data dimension reduction without a significant loss of discrimination power. Using 15 effective wavelengths, LDA model had a maximum accuracy of 100 %. PLSR model developed using the selected effective wavelengths also had robust performance, with R2 of 0.89, validation set. Findings confirm the high potential of hyperspectral imaging for non-destructive and accurate detection of fungal toxin contamination in plant food, suggesting its potential as a rapid and reliable method in food industry.

2026-01-01T00:00:00Z López Benito, Saray Sánchez Sánchez, Julia Brito, Verónica Calvo Enrique, Laura Lisa, Silvia Torres Valle, María Palko, Mary E. Vicente García, Cristina Fernándz Fernández, Seila Bolaños Hernández, Juan Pedro Ginés, Silvia Tessarollo, Lino Arévalo Martín, Juan Carlos http://hdl.handle.net/10366/168404 2025-12-20T01:00:47Z 2018-06-06T00:00:00Z

[EN]BDNF is a growth factor with important roles in the nervous system in both physiological and pathological conditions, but the mechanisms controlling its secretion are not completely understood. Here, we show that ARMS/Kidins220 negatively regulates BDNF secretion in neurons from the CNS and PNS. Downregulation of the ARMS/Kidins220 protein in the adult mouse brain increases regulated BDNF secretion, leading to its accumulation in the striatum. Interestingly, two mouse models of Huntington’s disease (HD) showed increased levels of ARMS/Kidins220 in the hippocampus and regulated BDNF secretion deficits. Importantly, reduction of ARMS/Kidins220 in hippocampal slices from HD mice reversed the impaired regulated BDNF release. Moreover, there are increased levels of ARMS/Kidins220 in the hippocampus and PFC of patients with HD. ARMS/Kidins220 regulates Synaptotagmin-IV levels, which has been previously observed to modulate BDNF secretion. These data indicate that ARMS/Kidins220 controls the regulated secretion of BDNF and might play a crucial role in the pathogenesis of HD

2018-06-06T00:00:00Z Sousa Valente, J. Calvo, L. Vacca, Antonio Simeoli, R. Arévalo Martín, Juan Carlos malcangio, M. http://hdl.handle.net/10366/168403 2025-12-19T01:00:57Z 2017-08-24T00:00:00Z

[EN]Objective Aiming to delineate novel neuro-immune mechanisms for NGF/TrkA signalling in osteoarthritis (OA) pain, we evaluated inflammatory changes in the knee joints following injection of monoiodoacetate (MIA) in mice carrying a TrkA receptor mutation (P782S; TrkA KI mice). Method In behavioural studies we monitored mechanical hypersensitivity following intra-articular MIA and oral prostaglandin D2 (PGD2) synthase inhibitor treatments. In immunohistochemical studies we quantified joint mast cell numbers, calcitonin gene-related peptide expression in synovia and dorsal root ganglia, spinal cord neuron activation and microgliosis. We quantified joint leukocyte infiltration by flow cytometry analysis, and PGD2 generation and cyclooxygenase-2 (COX-2) expression in mast cell lines by ELISA and Western blot. Results In TrkA KI mice we observed rapid development of mechanical hypersensitivity and amplification of dorsal horn neurons and microglia activation 7 days after MIA. In TrkA KI knee joints we detected significant leukocyte infiltration and mast cells located in the vicinity of synovial nociceptive fibres. We demonstrated that mast cells exposure to NGF results in up-regulation of COX-2 and increase of PGD2 production. Finally, we observed that a PGD2 synthase inhibitor prevented MIA-mechanical hypersensitivity in TrkA KI, at doses which were ineffective in wild type (WT) mice. Conclusion Using the TrkA KI mouse model, we delineated a novel neuro-immune pathway and suggest that NGF-induced production of PGD2 in joint mast cells is critical for referred mechanical hypersensitivity in OA, probably through the activation of PGD2 receptor 1 in nociceptors: TrkA blockade in mast cells constitutes a potential target for OA pain

2017-08-24T00:00:00Z Lao Rodríguez, Ana Belén Schröger, Erich Malmierca, Manuel S. http://hdl.handle.net/10366/168399 2025-12-19T01:00:59Z 2025-12-05T00:00:00Z

[EN]Omission responses have been proposed as neural signatures of predictive coding mechanisms that arise when expected sensory events fail to occur. These responses support the view that the brain actively generates and updates internal models to anticipate future events, rather than passively processing incoming sensory input. Importantly, omission responses offer a direct index of prediction error and prediction. They are modulated by the behavioral relevance and predictability of the omitted stimulus. Emerging studies have shown that omission responses occur across a range of auditory paradigms and involve complex interactions between excitatory and inhibitory neurons, particularly via feedforward inhibition of pyramidal cells by specific interneuron populations. When an anticipated stimulus is omitted, the resulting disinhibition of pyramidal neurons generates a prediction error signal; crucial for updating internal models and driving synaptic plasticity. This mechanism shares key features with mismatch negativity and corollary discharge, suggesting that overlapping cortical circuits are engaged in predictive processing. Taken together, these findings highlight the value of omission responses as electrophysiological markers of the brain's active prediction and prediction error signaling in auditory perception.

2025-12-05T00:00:00Z Amoghin, Meysam Latifi Arribas, Juan Ignacio Abbaspour Gilandeh, Yousef Tahmasebi, Mohammad http://hdl.handle.net/10366/168359 2025-12-17T01:02:12Z 2026-03-15T00:00:00Z

[EN]We explored the application of hyperspectral imaging (400–1100 nm) for non-destructive evaluation of peroxidase (POD) and polyphenol oxidase (PPO) enzymes responsible for browning processes in bell pepper (Capsicum annuum L.) cultivars. Several preprocessing techniques, including Standard Normal Variate (SNV), were applied to spectral data to enhance signal quality. Analysis using Partial Least Squares Regression (PLSR) showed that raw spectral data provided stronger correlations and lower prediction errors compared to processed. Discriminant spectral bands were identified using Support Vector Machine (SVM) combined with metaheuristic optimization, with SVM–Learning Automata (LA) resulting as the most effective wavelength selection strategy. Enzyme activities were then predicted using selected wavelengths with Artificial Neural Network (ANN) and PLSR models. Model performance was evaluated using the coefficient of determination (R2), Root Mean Square Error (RMSE), and Ratio of Performance to Deviation (RPD) on independent validation sets. ANN consistently outperformed PLSR, achieving high cultivar-specific R2 values for POD of 0.86, 0.93, and 0.98, for Orange, Yellow, and Red pepper varieties, respectively and PPO R2 values of 0.91, 0.97, and 0.99, for the same pepper cultivars. A combined “Total Model” integrating data from all cultivars further demonstrated robust generalization, with R2 values of 0.9082 for POD and 0.9604 for PPO. Findings confirm that hyperspectral imaging, coupled with an effective wavelength selection technique and ANN modeling provides a rapid, reliable, and robust approach for industrial evaluation of enzymatic activity in bell peppers. The proposed methodology offers significant potential for quality monitoring, process optimization, and large-scale application in industrial environments.

2026-03-15T00:00:00Z Bohórquez, Laura H. Malmierca, Manuel S. Hockley, Adam http://hdl.handle.net/10366/168358 2025-12-17T01:00:56Z 2025-11-25T00:00:00Z

[EN]Context-dependent sensory processing within the predictive coding framework relies on detecting mismatches between incoming stimuli and internal predictive models. Sensory deviants elicit prediction errors, seen as enhanced neural responses, that update these models and influence attention and behaviour. Although prediction errors have been widely observed across brain regions, the downstream processes remain poorly understood. In this study, we recorded electrocorticography in five urethane-anaesthetised rats and identified cortical slow oscillations, characterised by spontaneous transitions between ‘Up’ and ‘Down’ states. Deviant stimuli in an auditory oddball paradigm evoked an initial positive prediction error, followed by a prolonged, all-or-nothing response which spread in a travelling wave across the cortex. Identified as putative evoked cortical Up states, these responses were not evoked by standards, omissions or a many-standards control. Up states following deviants occurred more recently after a previous Up state when compared to spontaneous Up states. In preliminary data from an awake rat, long-latency Up states were not present spontaneously or evoked. In a different rat, anaesthetic depth was key to spontaneous and evoked Up states, with more robust Up/Down states and more reliable triggering of Up states under deeper anaesthesia. These results suggest that sensory deviants may cause shifts in cortical state under anaesthesia, explaining the long-latency mismatch response under anaesthesia and sleep.

2025-11-25T00:00:00Z