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1.
Nutrients ; 16(11)2024 May 21.
Article in English | MEDLINE | ID: mdl-38892486

ABSTRACT

BACKGROUND: A nationwide, prospective, multicenter, cohort study (the Disease-Related caloric-protein malnutrition EChOgraphy (DRECO) study) was designed to assess the usefulness of ultrasound of the rectus femoris for detecting sarcopenia in hospitalized patients at risk of malnutrition and to define cut-off values of ultrasound measures. METHODS: Patients at risk of malnutrition according to the Malnutrition Universal Screening Tool (MUST) underwent handgrip dynamometry, bioelectrical impedance analysis (BIA), a Timed Up and Go (TUG) test, and rectus femoris ultrasound studies. European Working Group on Sarcopenia in Older People (EWGSOP2) criteria were used to define categories of sarcopenia (at risk, probable, confirmed, severe). Receiver operating characteristic (ROC) and area under the curve (AUC) analyses were used to determine the optimal diagnostic sensitivity, specificity, and predictive values of cut-off points of the ultrasound measures for the detection of risk of sarcopenia and probable, confirmed, and severe sarcopenia. RESULTS: A total of 1000 subjects were included and 991 of them (58.9% men, mean age 58.5 years) were evaluated. Risk of sarcopenia was detected in 9.6% patients, probable sarcopenia in 14%, confirmed sarcopenia in 9.7%, and severe sarcopenia in 3.9%, with significant differences in the distribution of groups between men and women (p < 0.0001). The cross-sectional area (CSA) of the rectus femoris showed a significantly positive correlation with body cell mass of BIA and handgrip strength, and a significant negative correlation with TUG. Cut-off values were similar within each category of sarcopenia, ranging between 2.40 cm2 and 3.66 cm2 for CSA, 32.57 mm and 40.21 mm for the X-axis, and 7.85 mm and 10.4 mm for the Y-axis. In general, these cut-off values showed high sensitivities, particularly for the categories of confirmed and severe sarcopenia, with male patients also showing better sensitivities than women. CONCLUSIONS: Sarcopenia in hospitalized patients at risk of malnutrition was high. Cut-off values for the better sensitivities and specificities of ultrasound measures of the rectus femoris are established. The use of ultrasound of the rectus femoris could be used for the prediction of sarcopenia and be useful to integrate nutritional study into real clinical practice.


Subject(s)
Malnutrition , Quadriceps Muscle , Sarcopenia , Ultrasonography , Humans , Male , Sarcopenia/diagnostic imaging , Sarcopenia/diagnosis , Sarcopenia/etiology , Female , Ultrasonography/methods , Middle Aged , Prospective Studies , Aged , Quadriceps Muscle/diagnostic imaging , Malnutrition/diagnosis , Nutritional Status , Hand Strength , Nutrition Assessment , Electric Impedance , ROC Curve , Sensitivity and Specificity , Risk Factors , Geriatric Assessment/methods
2.
Proc Natl Acad Sci U S A ; 121(23): e2320489121, 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38805278

ABSTRACT

Neural oscillations reflect fluctuations in excitability, which biases the percept of ambiguous sensory input. Why this bias occurs is still not fully understood. We hypothesized that neural populations representing likely events are more sensitive, and thereby become active on earlier oscillatory phases, when the ensemble itself is less excitable. Perception of ambiguous input presented during less-excitable phases should therefore be biased toward frequent or predictable stimuli that have lower activation thresholds. Here, we show such a frequency bias in spoken word recognition using psychophysics, magnetoencephalography (MEG), and computational modelling. With MEG, we found a double dissociation, where the phase of oscillations in the superior temporal gyrus and medial temporal gyrus biased word-identification behavior based on phoneme and lexical frequencies, respectively. This finding was reproduced in a computational model. These results demonstrate that oscillations provide a temporal ordering of neural activity based on the sensitivity of separable neural populations.


Subject(s)
Language , Magnetoencephalography , Speech Perception , Humans , Speech Perception/physiology , Male , Female , Adult , Temporal Lobe/physiology , Young Adult , Models, Neurological
3.
PLoS Biol ; 22(5): e3002656, 2024 May.
Article in English | MEDLINE | ID: mdl-38820496

ABSTRACT

Negation is key for cognition but has no physical basis, raising questions about its neural origins. A new study in PLOS Biology on the negation of scalar adjectives shows that negation acts in part by altering the response to the adjective it negates.


Subject(s)
Brain , Cognition , Brain/physiology , Humans , Cognition/physiology , Behavior/physiology
4.
Rev Esp Salud Publica ; 982024 May 28.
Article in Spanish | MEDLINE | ID: mdl-38804329

ABSTRACT

Harm reduction is a classic Public Health concept to refer to the reduction of the negative effect of drug use/abuse with a focus on justice and human rights, but the tobacco industry has been perverting this concept for years and using it as a tool for its own marketing. This publication details what real harm reduction action on tobacco use would be, when it should be implemented, and what pillars it should be based on. Different methods of reducing the harmful effects of tobacco and nicotine have been tried and tested over time, but the results have been poor; therefore, smoking cessation by the various officially recognised methods is recommended as a priority objective, using the tools that are truly supported by science. In contrast, it also explains the strategies developed by the industry to manipulate consumers and make them dependent on products that can eventually kill them: from the development of filtered cigarettes to light cigarettes, and from menthol to flavoured vapes. In all cases, they have falsely led people to believe that they were developing less toxic products when they were not. Nowadays, both light and menthol cigarettes are banned in Spain, filters have not reduced risk but increased the use, and vapes try to replace cigarettes with their attractive flavours and their false legend of healthier products when what they are really doing is maintaining the same addiction by changing the object, encouraging dual use, and attracting younger and younger non-smokers. At the same time, a strategy of dividing the opinion of health professionals has been developed, using medical doctors and researchers with recognised conflicts of interest but who manage to confuse consumers. In conclusion, we consider that, although nicotine releasing devices may be useful elements in some particular cases, they are not recommended at the population level as they can promote onset, prevent cessation, as well as maintaining the addictive capacity. The only nicotine products that are recommended are those of pharmacological use approved for the case and provided they are used as a transitional tool to complete cessation.


La reducción de daños es un concepto clásico de la Salud Pública para referirse a la reducción del impacto negativo del consumo de drogas con un enfoque de justicia y derechos humanos, pero la industria tabacalera lleva años pervirtiendo este concepto y utilizándolo como una herramienta de su propio marketing. La presente publicación detalla qué sería una verdadera acción de reducción de daños en tabaquismo, cuándo debería aplicarse y en qué pilares debería sostenerse. A lo largo del tiempo se han probado distintos métodos de minorar los efectos perjudiciales del tabaco y de la nicotina, si bien los resultados han sido escasos; así pues, se propone como objetivo prioritario la cesación tabáquica por los distintos métodos reconocidos, utilizando como herramientas las verdaderamente amparadas por la Ciencia. En contraste, se explican también las estrategias desarrolladas por la industria para manipular a los consumidores y hacerles dependientes de unos productos que eventualmente pueden acabar con sus vidas: desde el desarrollo de los cigarrillos con filtro a los light, y de los mentolados a los vapers de sabores. En todos los casos han hecho creer falsamente que desarrollaban productos menos tóxicos cuando no era así. Hoy en día, tanto los cigarrillos light como los mentolados están prohibidos en España, los filtros no han conseguido una disminución del riesgo y sí un aumento del consumo, y los vapers intentan sustituir a los cigarrillos con sus aromas atractivos y su falsa leyenda de productos más sanos cuando lo que están haciendo en realidad es mantener la misma adicción cambiando el objeto, fomentando el consumo dual, y atrayendo a consumidores no-fumadores previos cada vez más jóvenes. Paralelamente, se ha desarrollado una estrategia de división de la opinión de los profesionales sanitarios, con médicos e investigadores con reconocidos conflictos de interés pero que logran confundir al consumidor. Como conclusión consideramos que, si bien en algún caso particular los DSLN (dispositivos susceptibles de liberar nicotina) puedan ser elementos útiles, no son recomendables a nivel poblacional ya que pueden promover el inicio del consumo e impedir la cesación, además de mantener la capacidad adictógena. Los únicos productos de nicotina que se recomiendan son aquellos de uso farmacológico aprobados para el caso y siempre que se usen como herramienta transitoria para la cesación completa.


Subject(s)
Harm Reduction , Public Health , Humans , Public Health/methods , Smoking Cessation/methods , Tobacco Use/prevention & control , Spain , Tobacco Industry/legislation & jurisprudence
5.
J Cogn Neurosci ; 36(7): 1472-1492, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38652108

ABSTRACT

Human language offers a variety of ways to create meaning, one of which is referring to entities, objects, or events in the world. One such meaning maker is understanding to whom or to what a pronoun in a discourse refers to. To understand a pronoun, the brain must access matching entities or concepts that have been encoded in memory from previous linguistic context. Models of language processing propose that internally stored linguistic concepts, accessed via exogenous cues such as phonological input of a word, are represented as (a)synchronous activities across a population of neurons active at specific frequency bands. Converging evidence suggests that delta band activity (1-3 Hz) is involved in temporal and representational integration during sentence processing. Moreover, recent advances in the neurobiology of memory suggest that recollection engages neural dynamics similar to those which occurred during memory encoding. Integrating from these two research lines, we here tested the hypothesis that neural dynamic patterns, especially in delta frequency range, underlying referential meaning representation, would be reinstated during pronoun resolution. By leveraging neural decoding techniques (i.e., representational similarity analysis) on a magnetoencephalogram data set acquired during a naturalistic story-listening task, we provide evidence that delta-band activity underlies referential meaning representation. Our findings suggest that, during spoken language comprehension, endogenous linguistic representations such as referential concepts may be proactively retrieved and represented via activation of their underlying dynamic neural patterns.


Subject(s)
Delta Rhythm , Magnetoencephalography , Humans , Male , Female , Adult , Young Adult , Delta Rhythm/physiology , Comprehension/physiology , Brain/physiology , Speech Perception/physiology , Psycholinguistics
6.
eNeuro ; 11(4)2024 Apr.
Article in English | MEDLINE | ID: mdl-38490743

ABSTRACT

Research into the role of brain oscillations in basic perceptual and cognitive functions has suggested that the alpha rhythm reflects functional inhibition while the beta rhythm reflects neural ensemble (re)activation. However, little is known regarding the generalization of these proposed fundamental operations to linguistic processes, such as speech comprehension and production. Here, we recorded magnetoencephalography in participants performing a novel rule-switching paradigm. Specifically, Dutch native speakers had to produce an alternative exemplar from the same category or a feature of a given target word embedded in spoken sentences (e.g., for the word "tuna", an exemplar from the same category-"seafood"-would be "shrimp", and a feature would be "pink"). A cue indicated the task rule-exemplar or feature-either before (pre-cue) or after (retro-cue) listening to the sentence. Alpha power during the working memory delay was lower for retro-cue compared with that for pre-cue in the left hemispheric language-related regions. Critically, alpha power negatively correlated with reaction times, suggestive of alpha facilitating task performance by regulating inhibition in regions linked to lexical retrieval. Furthermore, we observed a different spatiotemporal pattern of beta activity for exemplars versus features in the right temporoparietal regions, in line with the proposed role of beta in recruiting neural networks for the encoding of distinct categories. Overall, our study provides evidence for the generalizability of the role of alpha and beta oscillations from perceptual to more "complex, linguistic processes" and offers a novel task to investigate links between rule-switching, working memory, and word production.


Subject(s)
Brain , Language , Humans , Brain/physiology , Magnetoencephalography , Comprehension/physiology , Linguistics , Alpha Rhythm/physiology
7.
Article in English | MEDLINE | ID: mdl-38490245

ABSTRACT

OBJECTIVES: To provide an overview on the current use of belimumab (BLM) in SLE patients in clinical practice and to examine its efficacy in terms of standardized outcomes, drug survival, as well as patient and safety profiles. METHODS: A longitudinal retrospective multicentre cohort including SLE patients treated with BLM at 18 Spanish centers. Data was collected upon initiation of BLM, at 6 and 12 months after initiation, and at the last recorded visit. Changes in SLEDAI-2K, the proportion of patients who achieved LLDAS and DORIS 2021, and number of flares were compared between visits. Changes in damage, glucocorticoids use and employment status pre-BLM and post-BLM were also assessed. RESULTS: A total of 324 patients were included with a mean follow-up of 3.8 (±2.7) years. LLDAS was attained by 45.8%, 62% and 71% of patients, and DORIS by 24%, 36.2% and 52.5% on successive visits, respectively. Twenty-seven-point two percent of patients were in DORIS ≥ 50% of the visits and a 46% in LLDAS-50. Flares and number of flares were significantly lower one year after treatment with BLM and no changes in damage accrual were observed. Mean (±SD) prednisone dose was significantly reduced over time, with 70 (24%) patients discontinuing GC. CONCLUSION: Our study not only demonstrates belimumab´s efficacy in attaining treat-to-target goals in SLE patients, but also confirms its GC-sparing effect, and its prevention of flares and organ damage accrual.

8.
Neuropsychopharmacology ; 49(5): 837-844, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37741905

ABSTRACT

The prefrontal cortex (PFC) and extended frontostriatal circuitry play a critical role in executive cognitive processes that guide goal-directed behavior. Dysregulation of frontostriatal-dependent cognition is implicated in a variety of cognitive/behavioral disorders, including addiction and attention deficit hyperactivity disorder (ADHD). Psychostimulants exert dose-dependent and opposing actions on frontostriatal cognitive function. Specifically, low and clinically-relevant doses improve, while higher doses associated with abuse and addiction impair, frontostriatal-dependent cognitive function. Frontostriatal cognition is supported by the coordinated activity of neurons across this circuit. To date, the neural coding mechanisms that support the diverse cognitive actions of psychostimulants are unclear. This represents a significant deficit in our understanding of the neurobiology of frontostriatal cognition and limits the development of novel treatments for frontostriatal cognitive impairment. The current studies examined the effects of cognition-enhancing and cognition-impairing doses of methylphenidate (MPH) on the spiking activity of dorsomedial PFC (dmPFC) and dorsomedial striatal (dmSTR) neurons in 17 male rats engaged in a working memory task. Across this frontostriatal circuit, we observed opposing actions of low- and high-dose MPH on the population-based representation of delay: low-dose strengthened, while high-dose weakened, representation of this event. MPH elicited a more complex pattern of actions on reward-related signaling, that were highly dose-, region- and neuron-dependent. These observations provide novel insight into the neurophysiological mechanisms that support the cognitive actions of psychostimulants.


Subject(s)
Attention Deficit Disorder with Hyperactivity , Central Nervous System Stimulants , Methylphenidate , Rats , Male , Animals , Memory, Short-Term , Rats, Sprague-Dawley , Central Nervous System Stimulants/pharmacology , Central Nervous System Stimulants/therapeutic use , Methylphenidate/pharmacology , Methylphenidate/therapeutic use , Cognition , Attention Deficit Disorder with Hyperactivity/drug therapy , Prefrontal Cortex
9.
J Cogn Neurosci ; 36(1): 167-186, 2024 01 01.
Article in English | MEDLINE | ID: mdl-37847823

ABSTRACT

From a brain's-eye-view, when a stimulus occurs and what it is are interrelated aspects of interpreting the perceptual world. Yet in practice, the putative perceptual inferences about sensory content and timing are often dichotomized and not investigated as an integrated process. We here argue that neural temporal dynamics can influence what is perceived, and in turn, stimulus content can influence the time at which perception is achieved. This computational principle results from the highly interdependent relationship of what and when in the environment. Both brain processes and perceptual events display strong temporal variability that is not always modeled; we argue that understanding-and, minimally, modeling-this temporal variability is key for theories of how the brain generates unified and consistent neural representations and that we ignore temporal variability in our analysis practice at the peril of both data interpretation and theory-building. Here, we review what and when interactions in the brain, demonstrate via simulations how temporal variability can result in misguided interpretations and conclusions, and outline how to integrate and synthesize what and when in theories and models of brain computation.


Subject(s)
Brain Mapping , Brain , Humans
10.
J Pharmacol Exp Ther ; 387(2): 180-187, 2023 11.
Article in English | MEDLINE | ID: mdl-37714687

ABSTRACT

Interleukin (IL)-23 exists as a heterodimer consisting of p19 and p40 and is a key cytokine for promoting inflammatory responses in a variety of target organs. IL-23 plays a key role in the differentiation and maintenance of T helper 17 cells, and deregulation of IL-23 can result in autoimmune pathologies of the skin, lungs, and gut. This study describes the generation and characterization of mirikizumab (miri), a humanized IgG4 monoclonal antibody directed against the p19 subunit of IL-23. Miri binds human and cynomolgus monkey IL-23 with high affinity and binds rabbit IL-23 weakly but does not bind to rodent IL-23 or the other IL-23 family members IL-12, IL-27, or IL-35. Miri effectively inhibits the interaction of IL-23 with its receptor, and potently blocks IL-23-induced IL-17 production in cell-based assays while preserving the function of IL-12. In both local and systemic in vivo mouse models, miri blocked IL-23-induced keratin mRNA or IL-17 production, respectively. These data provide a comprehensive preclinical characterization of miri, for which efficacy and safety have been demonstrated in human clinical trials for psoriasis, ulcerative colitis, and Crohn's disease. SIGNIFICANCE STATEMENT: This article describes the generation and characterization of mirikizumab, a high affinity, neutralizing IgG4 variant monoclonal antibody that is under development for the treatment of ulcerative colitis and Crohn's disease. Neutralization of interleukin (IL)-23 is achieved by preventing the binding of IL-23 p19 subunit to the IL-23 receptor and does not affect the IL-12 pathway.


Subject(s)
Colitis, Ulcerative , Crohn Disease , Humans , Animals , Mice , Rabbits , Interleukin-23 , Colitis, Ulcerative/drug therapy , Interleukin-17 , Interleukin-23 Subunit p19 , Macaca fascicularis , Interleukins , Antibodies, Monoclonal , Interleukin-12/therapeutic use , Immunoglobulin G
12.
Front Physiol ; 14: 1236430, 2023.
Article in English | MEDLINE | ID: mdl-37772064

ABSTRACT

Background: SARS-CoV-2 infection affects the vascular endothelium, which mediates the inflammatory and thrombotic cascade. Moreover, alterations in the endothelium are related to arterial stiffness, which has been established as a marker of cardiovascular disease. The objective of this study is to analyse how the structure, vascular function, vascular ageing and endothelial damage are related to the biopsychological situation in adults diagnosed with persistent COVID and the differences by gender. Methods: This cross-sectional, descriptive, observational study will be carried out in the Primary Care Research Unit of Salamanca (APISAL) and in the BioSepsis laboratory of the University of Salamanca. The sample will be selected from the persistent COVID monographic office at the Internal Medicine Service of the University Hospital of Salamanca, and from the population of subjects diagnosed with persistent COVID in the clinical history of Primary Care. Through consecutive sampling, the study will include 300 individuals diagnosed with persistent COVID who meet the diagnosis criteria established by the WHO, after they sign the informed consent. Endothelial damage biomarkers will be measured using ELLA-SimplePlexTM technology (Biotechne). Their vascular structure and function will be analysed by measuring the carotid intima-media thickness (Sonosite Micromax); the pulse wave and carotid-femoral pulse wave velocity (cfPWV) will be recorded with Sphygmocor System®. Cardio Ankle Vascular Index (CAVI), brachial-ankle pulse wave velocity (baPWV) and ankle-brachial index will be analysed with Vasera VS-2000®. The integral assessment of the subjects with persistent COVID will be conducted with different scales that evaluate fatigue, sleep, dyspnea, quality of life, attention, nutrition state, and fragility. We will also evaluate their lifestyles (diet, physical activity, smoking habits and alcohol consumption), psychological factors, and cognitive deterioration, which will be gathered through validated questionnaires; moreover, physical activity will be objectively measured using a pedometer for 7 days. Body composition will be measured through impedance using an Inbody 230. Vascular ageing will be calculated with 10 and 90 percentiles of cfPWV and baPWV. Furthermore, we will analyse the presence of vascular injury in the retina, heart, kidneys and brain, as well as cardiovascular risk. Demographic and analytical variables will also be gathered. Discussion: Arterial stiffness reflects the mechanic and functional properties of the arterial wall, showing the changes in arterial pressure, blood flow, and vascular diameter that occur with each heartbeat. SARS-CoV-2 affects the endothelial cells that are infected with this virus, increasing the production of pro-inflammatory cytokines and pro-thrombotic factors, which can cause early vascular ageing and an increase of arterial stiffness. Persistent COVID is a complex heterogeneous disorder that affects the lives of millions of people worldwide. The identifications of potential risk factors to better understand who is at risk of developing persistent COVID is important, since this would enable early and appropriate clinical support. It is unknown whether vascular alterations caused by COVID-19 resolve after acute infection or remain over time, favouring the increase of arterial stiffness and early vascular ageing. Therefore, it is necessary to propose studies that analyse the evolution of persistent COVID in this group of patients, as well as the possible variables that influence it. Clinical Trial registration: ClinicalTrials.gov, identifier NCT05819840.

13.
Int J Mol Sci ; 24(15)2023 Aug 02.
Article in English | MEDLINE | ID: mdl-37569727

ABSTRACT

Proper brain development essentially depends on the timed availability of sufficient amounts of thyroid hormone (TH). This, in turn, necessitates a tightly regulated expression of TH signaling components such as TH transporters, deiodinases, and TH receptors in a brain region- and cell-specific manner from early developmental stages onwards. Abnormal TH levels during critical stages, as well as mutations in TH signaling components that alter the global and/or local thyroidal state, result in detrimental consequences for brain development and neurological functions that involve alterations in central neurotransmitter systems. Thus, the question as to how TH signaling is implicated in the development and maturation of different neurotransmitter and neuromodulator systems has gained increasing attention. In this review, we first summarize the current knowledge on the regulation of TH signaling components during brain development. We then present recent advances in our understanding on how altered TH signaling compromises the development of cortical glutamatergic neurons, inhibitory GABAergic interneurons, cholinergic and dopaminergic neurons. Thereby, we highlight novel mechanistic insights and point out open questions in this evolving research field.


Subject(s)
Receptors, Thyroid Hormone , Thyroid Hormones , Thyroid Hormones/metabolism , Receptors, Thyroid Hormone/metabolism , Thyroid Gland/metabolism , Brain/metabolism , Membrane Transport Proteins/metabolism
14.
J Infus Nurs ; 46(4): 223-231, 2023.
Article in English | MEDLINE | ID: mdl-37406337

ABSTRACT

Infused biologics, such as pegloticase, are a core component of managing uncontrolled gout, which is increasing in prevalence. Pegloticase is often the last line of therapy for patients with uncontrolled gout; therefore, achieving a successful course of treatment is critical. The infusion nurse's role in patient education, serum uric acid monitoring, and patient medication compliance is essential for ensuring patient safety and maximizing the number of patients who benefit from a full treatment course of pegloticase. Infusion nurses are on the front lines with patients and need to be educated on potential negative effects associated with the medications they infuse, such as infusion reactions, as well as risk management methods like patient screening and monitoring. Further, patient education provided by the infusion nurse plays a large role in empowering the patient to become their own advocate during pegloticase treatment. This educational overview includes a model patient case for pegloticase monotherapy, as well as one for pegloticase with immunomodulation and a step-by-step checklist for infusion nurses to refer to throughout the pegloticase infusion process. A video abstract is available for this article at http://links.lww.com/JIN/A105.


Subject(s)
Gout Suppressants , Gout , Humans , Gout Suppressants/therapeutic use , Gout Suppressants/adverse effects , Uric Acid/therapeutic use , Gout/drug therapy , Gout/chemically induced , Polyethylene Glycols/adverse effects
15.
Elife ; 122023 Jul 07.
Article in English | MEDLINE | ID: mdl-37417736

ABSTRACT

When we comprehend language from speech, the phase of the neural response aligns with particular features of the speech input, resulting in a phenomenon referred to as neural tracking. In recent years, a large body of work has demonstrated the tracking of the acoustic envelope and abstract linguistic units at the phoneme and word levels, and beyond. However, the degree to which speech tracking is driven by acoustic edges of the signal, or by internally-generated linguistic units, or by the interplay of both, remains contentious. In this study, we used naturalistic story-listening to investigate (1) whether phoneme-level features are tracked over and above acoustic edges, (2) whether word entropy, which can reflect sentence- and discourse-level constraints, impacted the encoding of acoustic and phoneme-level features, and (3) whether the tracking of acoustic edges was enhanced or suppressed during comprehension of a first language (Dutch) compared to a statistically familiar but uncomprehended language (French). We first show that encoding models with phoneme-level linguistic features, in addition to acoustic features, uncovered an increased neural tracking response; this signal was further amplified in a comprehended language, putatively reflecting the transformation of acoustic features into internally generated phoneme-level representations. Phonemes were tracked more strongly in a comprehended language, suggesting that language comprehension functions as a neural filter over acoustic edges of the speech signal as it transforms sensory signals into abstract linguistic units. We then show that word entropy enhances neural tracking of both acoustic and phonemic features when sentence- and discourse-context are less constraining. When language was not comprehended, acoustic features, but not phonemic ones, were more strongly modulated, but in contrast, when a native language is comprehended, phoneme features are more strongly modulated. Taken together, our findings highlight the flexible modulation of acoustic, and phonemic features by sentence and discourse-level constraint in language comprehension, and document the neural transformation from speech perception to language comprehension, consistent with an account of language processing as a neural filter from sensory to abstract representations.


Subject(s)
Comprehension , Linguistics , Comprehension/physiology , Language , Speech/physiology , Acoustics , Acoustic Stimulation/methods
16.
J Neurosci ; 43(26): 4867-4883, 2023 06 28.
Article in English | MEDLINE | ID: mdl-37221093

ABSTRACT

To understand language, we need to recognize words and combine them into phrases and sentences. During this process, responses to the words themselves are changed. In a step toward understanding how the brain builds sentence structure, the present study concerns the neural readout of this adaptation. We ask whether low-frequency neural readouts associated with words change as a function of being in a sentence. To this end, we analyzed an MEG dataset by Schoffelen et al. (2019) of 102 human participants (51 women) listening to sentences and word lists, the latter lacking any syntactic structure and combinatorial meaning. Using temporal response functions and a cumulative model-fitting approach, we disentangled delta- and theta-band responses to lexical information (word frequency), from responses to sensory and distributional variables. The results suggest that delta-band responses to words are affected by sentence context in time and space, over and above entropy and surprisal. In both conditions, the word frequency response spanned left temporal and posterior frontal areas; however, the response appeared later in word lists than in sentences. In addition, sentence context determined whether inferior frontal areas were responsive to lexical information. In the theta band, the amplitude was larger in the word list condition ∼100 milliseconds in right frontal areas. We conclude that low-frequency responses to words are changed by sentential context. The results of this study show how the neural representation of words is affected by structural context and as such provide insight into how the brain instantiates compositionality in language.SIGNIFICANCE STATEMENT Human language is unprecedented in its combinatorial capacity: we are capable of producing and understanding sentences we have never heard before. Although the mechanisms underlying this capacity have been described in formal linguistics and cognitive science, how they are implemented in the brain remains to a large extent unknown. A large body of earlier work from the cognitive neuroscientific literature implies a role for delta-band neural activity in the representation of linguistic structure and meaning. In this work, we combine these insights and techniques with findings from psycholinguistics to show that meaning is more than the sum of its parts; the delta-band MEG signal differentially reflects lexical information inside and outside sentence structures.


Subject(s)
Brain , Language , Humans , Female , Brain/physiology , Linguistics , Psycholinguistics , Brain Mapping , Semantics
17.
Front Immunol ; 14: 1163198, 2023.
Article in English | MEDLINE | ID: mdl-37207229

ABSTRACT

Background: Fibrostenotic disease is a common complication in Crohn's disease (CD) patients hallmarked by transmural extracellular matrix (ECM) accumulation in the intestinal wall. The prevention and medical therapy of fibrostenotic CD is an unmet high clinical need. Although targeting IL36R signaling is a promising therapy option, downstream mediators of IL36 during inflammation and fibrosis have been incompletely understood. Candidate molecules include matrix metalloproteinases which mediate ECM turnover and are thereby potential targets for anti-fibrotic treatment. Here, we have focused on understanding the role of MMP13 during intestinal fibrosis. Methods: We performed bulk RNA sequencing of paired colon biopsies taken from non-stenotic and stenotic areas of patients with CD. Corresponding tissue samples from healthy controls and CD patients with stenosis were used for immunofluorescent (IF) staining. MMP13 gene expression was analyzed in cDNA of intestinal biopsies from healthy controls and in subpopulations of patients with CD in the IBDome cohort. In addition, gene regulation on RNA and protein level was studied in colon tissue and primary intestinal fibroblasts from mice upon IL36R activation or blockade. Finally, in vivo studies were performed with MMP13 deficient mice and littermate controls in an experimental model of intestinal fibrosis. Ex vivo tissue analysis included Masson's Trichrome and Sirius Red staining as well as evaluation of immune cells, fibroblasts and collagen VI by IF analysis. Results: Bulk RNA sequencing revealed high upregulation of MMP13 in colon biopsies from stenotic areas, as compared to non-stenotic regions of patients with CD. IF analysis confirmed higher levels of MMP13 in stenotic tissue sections of CD patients and demonstrated αSMA+ and Pdpn+ fibroblasts as a major source. Mechanistic experiments demonstrated that MMP13 expression was regulated by IL36R signaling. Finally, MMP13 deficient mice, as compared to littermate controls, developed less fibrosis in the chronic DSS model and showed reduced numbers of αSMA+ fibroblasts. These findings are consistent with a model suggesting a molecular axis involving IL36R activation in gut resident fibroblasts and MMP13 expression during the pathogenesis of intestinal fibrosis. Conclusion: Targeting IL36R-inducible MMP13 could evolve as a promising approach to interfere with the development and progression of intestinal fibrosis.


Subject(s)
Crohn Disease , Animals , Mice , Matrix Metalloproteinase 13 , Crohn Disease/metabolism , Colon , Fibrosis , Constriction, Pathologic , Interleukins/metabolism
18.
Psychol Rev ; 130(4): 935-952, 2023 07.
Article in English | MEDLINE | ID: mdl-37166848

ABSTRACT

Since the cognitive revolution, language and action have been compared as cognitive systems, with cross-domain convergent views recently gaining renewed interest in biology, neuroscience, and cognitive science. Language and action are both combinatorial systems whose mode of combination has been argued to be hierarchical, combining elements into constituents of increasingly larger size. This structural similarity has led to the suggestion that they rely on shared cognitive and neural resources. In this article, we compare the conceptual and formal properties of hierarchy in language and action using set theory. We show that the strong compositionality of language requires a particular formalism, a magma, to describe the algebraic structure corresponding to the set of hierarchical structures underlying sentences. When this formalism is applied to actions, it appears to be both too strong and too weak. To overcome these limitations, which are related to the weak compositionality and sequential nature of action structures, we formalize the algebraic structure corresponding to the set of actions as a trace monoid. We aim to capture the different system properties of language and action in terms of the distinction between hierarchical sets and hierarchical sequences and discuss the implications for the way both systems could be represented in the brain. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Subject(s)
Brain , Language , Humans , Cognitive Science
19.
J Neurosci ; 43(20): 3718-3732, 2023 05 17.
Article in English | MEDLINE | ID: mdl-37059462

ABSTRACT

Brain oscillations are prevalent in all species and are involved in numerous perceptual operations. α oscillations are thought to facilitate processing through the inhibition of task-irrelevant networks, while ß oscillations are linked to the putative reactivation of content representations. Can the proposed functional role of α and ß oscillations be generalized from low-level operations to higher-level cognitive processes? Here we address this question focusing on naturalistic spoken language comprehension. Twenty-two (18 female) Dutch native speakers listened to stories in Dutch and French while MEG was recorded. We used dependency parsing to identify three dependency states at each word: the number of (1) newly opened dependencies, (2) dependencies that remained open, and (3) resolved dependencies. We then constructed forward models to predict α and ß power from the dependency features. Results showed that dependency features predict α and ß power in language-related regions beyond low-level linguistic features. Left temporal, fundamental language regions are involved in language comprehension in α, while frontal and parietal, higher-order language regions, and motor regions are involved in ß. Critically, α- and ß-band dynamics seem to subserve language comprehension tapping into syntactic structure building and semantic composition by providing low-level mechanistic operations for inhibition and reactivation processes. Because of the temporal similarity of the α-ß responses, their potential functional dissociation remains to be elucidated. Overall, this study sheds light on the role of α and ß oscillations during naturalistic spoken language comprehension, providing evidence for the generalizability of these dynamics from perceptual to complex linguistic processes.SIGNIFICANCE STATEMENT It remains unclear whether the proposed functional role of α and ß oscillations in perceptual and motor function is generalizable to higher-level cognitive processes, such as spoken language comprehension. We found that syntactic features predict α and ß power in language-related regions beyond low-level linguistic features when listening to naturalistic speech in a known language. We offer experimental findings that integrate a neuroscientific framework on the role of brain oscillations as "building blocks" with spoken language comprehension. This supports the view of a domain-general role of oscillations across the hierarchy of cognitive functions, from low-level sensory operations to abstract linguistic processes.


Subject(s)
Comprehension , Speech Perception , Female , Humans , Comprehension/physiology , Magnetoencephalography , Brain/physiology , Language , Linguistics , Brain Mapping/methods , Speech Perception/physiology
20.
Cereb Cortex ; 33(12): 7857-7869, 2023 06 08.
Article in English | MEDLINE | ID: mdl-36935095

ABSTRACT

Goal-directed behavior is dependent on neuronal activity in the prefrontal cortex (PFC) and extended frontostriatal circuitry. Stress and stress-related disorders are associated with impaired frontostriatal-dependent cognition. Our understanding of the neural mechanisms that underlie stress-related cognitive impairment is limited, with the majority of prior research focused on the PFC. To date, the actions of stress across cognition-related frontostriatal circuitry are unknown. To address this gap, the current studies examined the effects of acute noise-stress on the spiking activity of neurons and local field potential oscillatory activity within the dorsomedial PFC (dmPFC) and dorsomedial striatum (dmSTR) in rats engaged in a test of spatial working memory. Stress robustly suppressed responses of both dmPFC and dmSTR neurons strongly tuned to key task events (delay, reward). Additionally, stress strongly suppressed delay-related, but not reward-related, theta and alpha spectral power within, and synchrony between, the dmPFC and dmSTR. These observations provide the first demonstration that stress disrupts the neural coding and functional connectivity of key task events, particularly delay, within cognition-supporting dorsomedial frontostriatal circuitry. These results suggest that stress-related degradation of neural coding within both the PFC and striatum likely contributes to the cognition-impairing effects of stress.


Subject(s)
Corpus Striatum , Memory, Short-Term , Rats , Animals , Memory, Short-Term/physiology , Corpus Striatum/physiology , Neostriatum , Prefrontal Cortex/physiology , Neurons/physiology
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