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1.
Obstet Gynecol ; 143(1): 83-91, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37562052

RESUMEN

OBJECTIVE: To assess whether coronavirus disease 2019 (COVID-19) is associated with menstrual cycle length changes and, if so, how that compares with those undergoing vaccination or no event (control). METHODS: We conducted a retrospective cohort analysis in which we analyzed prospectively tracked cycle-length data from users of a period tracker application who also responded to a survey regarding COVID-19 symptoms and vaccination. We restricted our sample to users aged 16-45 years, with normal cycle lengths (24-38 days) and regular tracking behavior during the five cycles around COVID-19 symptoms or vaccination or a similar time period for those experiencing no event (control group). We calculated the within-user change in cycle length (days) from the three consecutive cycles preevent average (either vaccination, disease, or neither; cycles 1-3) to the event (cycle 4) and postevent (cycle 5) cycles. We used mixed-effects models to estimate the age- and country-adjusted difference in change in cycle length across the groups. RESULTS: We included 6,514 users from 110 countries representing 32,570 cycles (COVID-19 symptoms: 1,450; COVID-19 vaccination: 4,643; control: 421). The COVID-19 cohort experienced a 1.45-day adjusted increase in cycle length during cycle 4 (COVID-19) compared with their three preevent cycles (95% CI 0.86-2.04). The vaccinated group experienced a 1.14-day adjusted increase in cycle length during cycle 4 (COVID-19 vaccine) compared with their preevent average (95% CI 0.60-1.69). The control group (neither vaccine nor disease) experienced a 0.68-day decrease (95% CI -1.18 to -0.19) in a similar time period. Post hoc tests showed no significant differences in the magnitude of changes between the COVID-19 and vaccination cohorts. In both cohorts, cycle length changes disappeared in the postevent cycle. CONCLUSION: Experiencing COVID-19 is associated with a small change in cycle length similar to COVID-19 vaccination. These changes resolve quickly within the next cycle.


Asunto(s)
COVID-19 , Femenino , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , Vacunas contra la COVID-19 , Estudios Retrospectivos , Vacunación , Ciclo Menstrual
2.
Death Stud ; 47(9): 983-993, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36519253

RESUMEN

Research indicates that final conversations with dying loved ones are significant but challenging relational events for survivors. Using a qualitative theme analysis, the present study documented survivors' (N = 44) retrospective reports of experiences of regret during final conversations. The analysis revealed experiences of validation regret, intersubjective regret, and encumbrance regret, and the use of regret management techniques. This knowledge is useful because it points to the impetus of regret experienced during final conversations and implicates communication patterns that could negatively impact bereavement.


Asunto(s)
Aflicción , Emociones , Humanos , Estudios Retrospectivos , Pesar , Comunicación , Sobrevivientes
3.
BMC Musculoskelet Disord ; 23(1): 488, 2022 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-35606809

RESUMEN

BACKGROUND: Low back pain has been associated with obesity or with being overweight. However, there are no high-quality systematic reviews that have been conducted on the effect of all types of weight loss programs focused on individuals with low back pain. Therefore, the present systematic review aims to evaluate the effectiveness of weight loss programs in reducing back pain and disability or increasing quality of life for individuals experiencing low back pain. MATERIALS AND METHODS: Searches for relevant studies were conducted on CINAHL, Web of Science, Ovid Medline, Ovid Embase and AMED. Studies were included if they were randomized controlled trials, non-randomized studies of intervention or quasi-experimental designs evaluating a weight loss program for persons with low back pain aimed at decreasing back pain and disability. The Effective Public Health Practice Project (EPHPP) Quality Assessment Tool was used to evaluate individual studies and GRADE was used to summarize the quality of the evidence. The review was prospectively registered; PROSPERO#: CRD42020196099. RESULTS: Eleven studies (n = 689 participants) including one randomized controlled trial, two non-randomized studies of intervention and eight single-arm studies were included (seven of which evaluated bariatric surgery). There was low-quality evidence that a lifestyle intervention was no better than waitlist for improving back pain and very low-quality evidence from single-arm studies that back pain improved from baseline after bariatric surgery. Most studies included were of poor quality, primarily due to selection bias, uncontrolled confounders, and lack of blinding, limiting the quality of evidence. CONCLUSION: There is very low-quality evidence that weight loss programs may improve back pain, disability, and quality of life in patients with LBP, although adherence and maintenance are potential barriers to implementation.


Asunto(s)
Dolor de la Región Lumbar , Programas de Reducción de Peso , Dolor de Espalda , Humanos , Dolor de la Región Lumbar/diagnóstico , Dolor de la Región Lumbar/terapia , Calidad de Vida
4.
Cereb Cortex ; 32(7): 1405-1418, 2022 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-34491301

RESUMEN

The neurobiology of sentence production has been largely understudied compared to the neurobiology of sentence comprehension, due to difficulties with experimental control and motion-related artifacts in neuroimaging. We studied the neural response to constituents of increasing size and specifically focused on the similarities and differences in the production and comprehension of the same stimuli. Participants had to either produce or listen to stimuli in a gradient of constituent size based on a visual prompt. Larger constituent sizes engaged the left inferior frontal gyrus (LIFG) and middle temporal gyrus (LMTG) extending to inferior parietal areas in both production and comprehension, confirming that the neural resources for syntactic encoding and decoding are largely overlapping. An ROI analysis in LIFG and LMTG also showed that production elicited larger responses to constituent size than comprehension and that the LMTG was more engaged in comprehension than production, while the LIFG was more engaged in production than comprehension. Finally, increasing constituent size was characterized by later BOLD peaks in comprehension but earlier peaks in production. These results show that syntactic encoding and parsing engage overlapping areas, but there are asymmetries in the engagement of the language network due to the specific requirements of production and comprehension.


Asunto(s)
Comprensión , Lenguaje , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Mapeo Encefálico , Comprensión/fisiología , Humanos , Imagen por Resonancia Magnética/métodos
5.
Children (Basel) ; 8(8)2021 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-34438514

RESUMEN

(1) Background: Carpal tunnel syndrome (CTS), a compressive mononeuropathy of the median nerve at the wrist, is rare in childhood and occurs most frequently due to secondary causes. (2) Methods: Medical history, electrodiagnostic findings, and imaging data of patients with CTS from two pediatric neuromuscular centers were analyzed retrospectively. The etiology of CTS was investigated and compared with the literature. (3) Results: We report on a cohort of 38 CTS patients (n = 22 females, n = 29 bilateral, mean age at diagnosis 9.8 years). Electrodiagnostic studies of all patients revealed slowing of the antidromic sensory or orthodromic mixed nerve conduction velocities across the carpal tunnel or lack of the sensory nerve action potential and/or prolonged distal motor latencies. Median nerve ultrasound was diagnostic for CTS and confirmed tumorous and vascular malformations. Etiology was secondary in most patients (n = 29; 76%), and mucopolysaccharidosis was the most frequent underlying condition (n = 14; 37%). Idiopathic CTS was rare in this pediatric cohort (n = 9; 24%). (4) Conclusion: Since CTS in childhood is predominantly caused by an underlying disorder, a thorough evaluation and search for a causative condition is recommended in this age group.

6.
Palliat Support Care ; 19(3): 335-340, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33155536

RESUMEN

OBJECTIVE: This is a pilot study with a primary goal to develop an effective, targeted educational intervention that can serve as a teaching tool to educate African American (AA) population, especially the elderly, on options of end of life (EOL) prior to critical care. METHOD: We first assessed the level of preparation for EOL in the AA community through a survey instrument. The survey was used to determine the deficits in knowledge in AA population in Mid-Michigan regarding EOL choices before and after the educational intervention. Paired-sample t-test was used to assess changes in understanding about EOL planning options. Regressions analysis was used to assess these changes while including several demographic covariates. P < 0.05 was considered statistically significant. RESULTS: Our pilot data indicated that the educational intervention could be used as an effective teaching tool in educating AA population on EOL choices. SIGNIFICANCE OF RESULTS: AA patients are more likely to choose life-sustaining measures at the end of their lives compared to other ethnic groups despite terminal illness. This decision is partly based on lack of knowledge of the available options of care at the EOL. Due to multiple life-sustaining measures, the AA patients are not receiving the care to help them peacefully die. This study provides evidence that physicians will need to increase their educational efforts with the AA population to help them better understand EOL options. An educational tool like the one developed in this study may be helpful and lessen the time of education so that the physician can answer any questions at the end of the session and also empower individuals and communities to take an active role in creating a culture of wellness at the EOL and decreasing morbidity.


Asunto(s)
Médicos , Cuidado Terminal , Negro o Afroamericano , Anciano , Muerte , Humanos , Proyectos Piloto
7.
Cortex ; 130: 111-126, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32652339

RESUMEN

Speakers and listeners usually interact in larger discourses than single words or even single sentences. The goal of the present study was to identify the neural bases reflecting how the mental representation of the situation denoted in a multi-sentence discourse (situation model) is constructed and shared between speakers and listeners. An fMRI study using a variant of the ambiguous text paradigm was designed. Speakers (n = 15) produced ambiguous texts in the scanner and listeners (n = 27) subsequently listened to these texts in different states of ambiguity: preceded by a highly informative, intermediately informative or no title at all. Conventional BOLD activation analyses in listeners, as well as inter-subject correlation analyses between the speakers' and the listeners' hemodynamic time courses were performed. Critically, only the processing of disambiguated, coherent discourse with an intelligible situation model representation involved (shared) activation in bilateral lateral parietal and medial prefrontal regions. This shared spatiotemporal pattern of brain activation between the speaker and the listener suggests that the process of memory retrieval in medial prefrontal regions and the binding of retrieved information in the lateral parietal cortex constitutes a core mechanism underlying the communication of complex conceptual representations.


Asunto(s)
Comprensión , Percepción del Habla , Encéfalo/diagnóstico por imagen , Humanos , Lenguaje , Imagen por Resonancia Magnética
8.
Schizophr Bull ; 46(6): 1558-1566, 2020 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-32432697

RESUMEN

It has been proposed that abnormalities in probabilistic prediction and dynamic belief updating explain the multiple features of schizophrenia. Here, we used electroencephalography (EEG) to ask whether these abnormalities can account for the well-established reduction in semantic priming observed in schizophrenia under nonautomatic conditions. We isolated predictive contributions to the neural semantic priming effect by manipulating the prime's predictive validity and minimizing retroactive semantic matching mechanisms. We additionally examined the link between prediction and learning using a Bayesian model that probed dynamic belief updating as participants adapted to the increase in predictive validity. We found that patients were less likely than healthy controls to use the prime to predictively facilitate semantic processing on the target, resulting in a reduced N400 effect. Moreover, the trial-by-trial output of our Bayesian computational model explained between-group differences in trial-by-trial N400 amplitudes as participants transitioned from conditions of lower to higher predictive validity. These findings suggest that, compared with healthy controls, people with schizophrenia are less able to mobilize predictive mechanisms to facilitate processing at the earliest stages of accessing the meanings of incoming words. This deficit may be linked to a failure to adapt to changes in the broader environment. This reciprocal relationship between impairments in probabilistic prediction and Bayesian learning/adaptation may drive a vicious cycle that maintains cognitive disturbances in schizophrenia.


Asunto(s)
Adaptación Psicológica/fisiología , Anticipación Psicológica/fisiología , Corteza Cerebral/fisiopatología , Aprendizaje por Probabilidad , Trastornos Psicóticos/fisiopatología , Esquizofrenia/fisiopatología , Adulto , Electroencefalografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Semántica
9.
J Cogn Neurosci ; 32(8): 1466-1483, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32319867

RESUMEN

This neuroimaging study investigated the neural infrastructure of sentence-level language production. We compared brain activation patterns, as measured with BOLD-fMRI, during production of sentences that differed in verb argument structures (intransitives, transitives, ditransitives) and the lexical status of the verb (known verbs or pseudoverbs). The experiment consisted of 30 mini-blocks of six sentences each. Each mini-block started with an example for the type of sentence to be produced in that block. On each trial in the mini-blocks, participants were first given the (pseudo-)verb followed by three geometric shapes to serve as verb arguments in the sentences. Production of sentences with known verbs yielded greater activation compared to sentences with pseudoverbs in the core language network of the left inferior frontal gyrus, the left posterior middle temporal gyrus, and a more posterior middle temporal region extending into the angular gyrus, analogous to effects observed in language comprehension. Increasing the number of verb arguments led to greater activation in an overlapping left posterior middle temporal gyrus/angular gyrus area, particularly for known verbs, as well as in the bilateral precuneus. Thus, producing sentences with more complex structures using existing verbs leads to increased activation in the language network, suggesting some reliance on memory retrieval of stored lexical-syntactic information during sentence production. This study thus provides evidence from sentence-level language production in line with functional models of the language network that have so far been mainly based on single-word production, comprehension, and language processing in aphasia.


Asunto(s)
Afasia , Lenguaje , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Comprensión , Humanos
10.
Proc Natl Acad Sci U S A ; 116(42): 21185-21190, 2019 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-31570628

RESUMEN

Interactions between top-down and bottom-up information streams are integral to brain function but challenging to measure noninvasively. Laminar resolution, functional MRI (lfMRI) is sensitive to depth-dependent properties of the blood oxygen level-dependent (BOLD) response, which can be potentially related to top-down and bottom-up signal contributions. In this work, we used lfMRI to dissociate the top-down and bottom-up signal contributions to the left occipitotemporal sulcus (LOTS) during word reading. We further demonstrate that laminar resolution measurements could be used to identify condition-specific distributed networks on the basis of whole-brain connectivity patterns specific to the depth-dependent BOLD signal. The networks corresponded to top-down and bottom-up signal pathways targeting the LOTS during word reading. We show that reading increased the top-down BOLD signal observed in the deep layers of the LOTS and that this signal uniquely related to the BOLD response in other language-critical regions. These results demonstrate that lfMRI can reveal important patterns of activation that are obscured at standard resolution. In addition to differences in activation strength as a function of depth, we also show meaningful differences in the interaction between signals originating from different depths both within a region and with the rest of the brain. We thus show that lfMRI allows the noninvasive measurement of directed interaction between brain regions and is capable of resolving different connectivity patterns at submillimeter resolution, something previously considered to be exclusively in the domain of invasive recordings.


Asunto(s)
Encéfalo/fisiología , Transducción de Señal/fisiología , Mapeo Encefálico/métodos , Humanos , Lenguaje , Imagen por Resonancia Magnética/métodos , Lectura
11.
Brain Behav ; 9(7): e01308, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31197970

RESUMEN

INTRODUCTION: Words are not processed in isolation but in rich contexts that are used to modulate and facilitate language comprehension. Here, we investigate distinct neural networks underlying two types of contexts, the current linguistic environment and verb-based syntactic preferences. METHODS: We had two main manipulations. The first was the current linguistic environment, where the relative frequencies of two syntactic structures (prepositional object [PO] and double-object [DO]) would either follow everyday linguistic experience or not. The second concerned the preference toward one or the other structure depending on the verb; learned in everyday language use and stored in memory. German participants were reading PO and DO sentences in German while brain activity was measured with functional magnetic resonance imaging. RESULTS: First, the anterior cingulate cortex (ACC) showed a pattern of activation that integrated the current linguistic environment with everyday linguistic experience. When the input did not match everyday experience, the unexpected frequent structure showed higher activation in the ACC than the other conditions and more connectivity from the ACC to posterior parts of the language network. Second, verb-based surprisal of seeing a structure given a verb (PO verb preference but DO structure presentation) resulted, within the language network (left inferior frontal and left middle/superior temporal gyrus) and the precuneus, in increased activation compared to a predictable verb-structure pairing. CONCLUSION: In conclusion, (1) beyond the canonical language network, brain areas engaged in prediction and error signaling, such as the ACC, might use the statistics of syntactic structures to modulate language processing, (2) the language network is directly engaged in processing verb preferences. These two networks show distinct influences on sentence processing.


Asunto(s)
Comprensión/fisiología , Lenguaje , Imagen por Resonancia Magnética/métodos , Medio Social , Vocabulario , Adulto , Mapeo Encefálico/métodos , Femenino , Lóbulo Frontal/diagnóstico por imagen , Humanos , Masculino , Lóbulo Parietal/diagnóstico por imagen , Psicolingüística , Lóbulo Temporal/diagnóstico por imagen , Conducta Verbal/fisiología
12.
Soc Cogn Affect Neurosci ; 14(6): 613-621, 2019 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-31087068

RESUMEN

A large literature in social neuroscience has associated the medial prefrontal cortex (mPFC) with the processing of self-related information. However, only recently have social neuroscience studies begun to consider the large behavioral literature showing a strong self-positivity bias, and these studies have mostly focused on its correlates during self-related judgments and decision-making. We carried out a functional MRI (fMRI) study to ask whether the mPFC would show effects of the self-positivity bias in a paradigm that probed participants' self-concept without any requirement of explicit self-judgment. We presented social vignettes that were either self-relevant or non-self-relevant with a neutral, positive or negative outcome described in the second sentence. In previous work using event-related potentials, this paradigm has shown evidence of a self-positivity bias that influences early stages of semantically processing incoming stimuli. In the present fMRI study, we found evidence for this bias within the mPFC: an interaction between self-relevance and valence, with only positive scenarios showing a self vs other effect within the mPFC. We suggest that the mPFC may play a role in maintaining a positively biased self-concept and discuss the implications of these findings for the social neuroscience of the self and the role of the mPFC.


Asunto(s)
Comprensión/fisiología , Juicio/fisiología , Corteza Prefrontal/diagnóstico por imagen , Autoimagen , Percepción Social , Adolescente , Femenino , Humanos , Imagen por Resonancia Magnética , Adulto Joven
13.
Neuropsychologia ; 124: 337-349, 2019 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-30391565

RESUMEN

It has been hypothesized that schizophrenia is characterized by overly broad automatic activity within lexico-semantic networks. We used two complementary neuroimaging techniques, Magnetoencephalography (MEG) and functional Magnetic Resonance Imaging (fMRI), in combination with a highly automatic indirect semantic priming paradigm, to spatiotemporally localize this abnormality in the brain. Eighteen people with schizophrenia and 20 demographically-matched control participants viewed target words ("bell") preceded by directly related ("church"), indirectly related ("priest"), or unrelated ("hammer") prime words in MEG and fMRI sessions. To minimize top-down processing, the prime was masked, the target appeared only 140 ms after prime onset, and participants simply monitored for words within a particular semantic category that appeared in filler trials. Both techniques revealed a significantly larger automatic indirect priming effect in people with schizophrenia than in control participants. MEG temporally localized this enhanced effect to the N400 time window (300-500 ms) - the critical stage of accessing meaning from words. fMRI spatially localized the effect to the left temporal fusiform cortex, which plays a role in mapping of orthographic word-form on to meaning. There was no evidence of an enhanced automatic direct semantic priming effect in the schizophrenia group. These findings provide converging neural evidence for abnormally broad highly automatic lexico-semantic activity in schizophrenia. We argue that, rather than arising from an unconstrained spread of automatic activation across semantic memory, this broader automatic lexico-semantic activity stems from looser mappings between the form and meaning of words.


Asunto(s)
Encéfalo/fisiopatología , Esquizofrenia/fisiopatología , Psicología del Esquizofrénico , Semántica , Adulto , Mapeo Encefálico , Potenciales Evocados , Femenino , Humanos , Imagen por Resonancia Magnética , Magnetoencefalografía , Masculino , Persona de Mediana Edad , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/fisiopatología , Enmascaramiento Perceptual , Esquizofrenia/diagnóstico por imagen
14.
Scand J Pain ; 17: 146-149, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28946059

RESUMEN

BACKGROUND AND PURPOSE: The purpose of this case report is to describe a multimodal pain therapeutic concept including the adjunct use of pregabalin in a 4.5 year-old child after forefoot amputation. Phantom limb pain and sensation is a complex pain syndrome that is difficult to treat and prevent. 70-75% of all children develop such a pain syndrome after amputation. We describe here a paediatric patient who underwent forefoot amputation following traumatic foot injury and received multimodal pain therapy including pregabalin. METHODS: A 4.5 year-old otherwise healthy girl suffered severe injuries of the right foot and lower leg during a motor vehicle accident. Due to development of severe necrosis, forefoot amputation had to be performed during the hospital stay. RESULTS: Initial pain therapy included paracetamol, ibuprofen, metamizol, morphine and fentanyl. With mounting pain and anxiety, regional anaesthesia of the distal sciatic nerve was administered in combination with a ketamine and morphine patient controlled analgesia pump (PCA). The peripheral blockade of the distal sciatic nerve was placed with the guidance of ultrasound and nerve stimulator. The PCA concept included a continuous basal rate combined with a bolus function. Although the regional anaesthesia was well positioned and functioning, there was inadequate pain control. The pain was described by the patient as short, highly intense and sharp sensations with intensity on the visual analogue scale (VAS) of 10 (out of 10). Furthermore, she suffered from anxiety episodes and sleep disturbance. The medical team decided to treat with pregabalin to resolve these issues while awaiting amputation (Lisfranc line). She received psychological counselling as adjunct treatment. This multimodal concept enabled an early and efficient pain reduction pre- and post-amputation and allowed for the possibility of a hospital discharge without any opioid pain medication. CONCLUSION: The multimodal pain therapy including pregabalin was well tolerated, safe and highly effective in this case of traumatic limb injury and subsequent amputation. The use of pregabalin allowed significant pain and anxiety reduction for the patient. IMPLICATIONS: Pregabalin is frequently used in adult patients for severe complex pain syndromes. There are only few reports of such adjunct medication (pregabalin) in paediatric pain syndromes. These reports focus mainly on the paediatric oncologic population. The case reported here encourages physicians to consider adjunct medications when treating complex pain, which are well established in the adult population. The benefits of such therapy in complex pain and anxiety can be extended to the paediatric population in select cases. Of course, one must always take into account that many routine medications used in children are well established but are off-label use. The authors are well aware of this problem and have conducted a critical literature review prior to pregabalin administration, including the search for randomized trials examining safety and tolerability. The parents or legal guardians of a minor must be thoroughly informed and consent to such a constellation of medical treatment.


Asunto(s)
Amputación Quirúrgica/métodos , Analgesia Controlada por el Paciente/métodos , Analgésicos/uso terapéutico , Pie/cirugía , Miembro Fantasma/tratamiento farmacológico , Pregabalina/uso terapéutico , Preescolar , Femenino , Humanos , Dimensión del Dolor
15.
Qual Health Res ; 27(10): 1575-1585, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28728531

RESUMEN

In this article, we offer insights into how individuals with cystic fibrosis (CF) share information about their disease with a romantic partner. Using communication privacy management as a sensitizing theoretical construct, four themes emerged following 13 qualitative interviews with persons with CF. Themes about sharing CF-related information with a romantic partner include weighing the risks and benefits of sharing information, the role of health-related triggered rules, the motivations for disclosures, and the reactions from outsiders. Implications of the research suggest a need for more nuanced understandings of how privacy rules are communicated in relationships, how the mismanagement of co-owned information influences future disclosures, how the public-private nature of rare genetic illnesses is managed, and how people with genetic illnesses make disclosure decisions.


Asunto(s)
Comunicación , Fibrosis Quística/psicología , Revelación , Difusión de la Información , Parejas Sexuales/psicología , Adulto , Femenino , Humanos , Masculino
16.
J Neurosci ; 36(26): 6872-80, 2016 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-27358446

RESUMEN

UNLABELLED: When learning a new language, we build brain networks to process and represent the acquired words and syntax and integrate these with existing language representations. It is an open question whether the same or different neural mechanisms are involved in learning and processing a novel language compared with the native language(s). Here we investigated the neural repetition effects of repeating known and novel word orders while human subjects were in the early stages of learning a new language. Combining a miniature language with a syntactic priming paradigm, we examined the neural correlates of language learning on-line using functional magnetic resonance imaging. In left inferior frontal gyrus and posterior temporal cortex, the repetition of novel syntactic structures led to repetition enhancement, whereas repetition of known structures resulted in repetition suppression. Additional verb repetition led to an increase in the syntactic repetition enhancement effect in language-related brain regions. Similarly, the repetition of verbs led to repetition enhancement effects in areas related to lexical and semantic processing, an effect that continued to increase in a subset of these regions. Repetition enhancement might reflect a mechanism to build and strengthen a neural network to process novel syntactic structures and lexical items. By contrast, the observed repetition suppression points to overlapping neural mechanisms for native and new language constructions when these have sufficient structural similarities. SIGNIFICANCE STATEMENT: Acquiring a second language entails learning how to interpret novel words and relations between words, and to integrate them with existing language knowledge. To investigate the brain mechanisms involved in this particularly human skill, we combined an artificial language learning task with a syntactic repetition paradigm. We show that the repetition of novel syntactic structures, as well as words in contexts, leads to repetition enhancement, whereas repetition of known structures results in repetition suppression. We thus propose that repetition enhancement might reflect a brain mechanism to build and strengthen a neural network to process novel syntactic regularities and novel words. Importantly, the results also indicate an overlap in neural mechanisms for native and new language constructions with sufficient structural similarities.


Asunto(s)
Mapeo Encefálico , Lenguaje , Imagen por Resonancia Magnética , Semántica , Percepción del Habla/fisiología , Lóbulo Temporal/fisiología , Aprendizaje Verbal/fisiología , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Oxígeno/sangre , Lóbulo Temporal/diagnóstico por imagen , Factores de Tiempo , Traducción
17.
PLoS One ; 11(3): e0148637, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27010386

RESUMEN

Probabilistic prediction plays a crucial role in language comprehension. When predictions are fulfilled, the resulting facilitation allows for fast, efficient processing of ambiguous, rapidly-unfolding input; when predictions are not fulfilled, the resulting error signal allows us to adapt to broader statistical changes in this input. We used functional Magnetic Resonance Imaging to examine the neuroanatomical networks engaged in semantic predictive processing and adaptation. We used a relatedness proportion semantic priming paradigm, in which we manipulated the probability of predictions while holding local semantic context constant. Under conditions of higher (versus lower) predictive validity, we replicate previous observations of reduced activity to semantically predictable words in the left anterior superior/middle temporal cortex, reflecting facilitated processing of targets that are consistent with prior semantic predictions. In addition, under conditions of higher (versus lower) predictive validity we observed significant differences in the effects of semantic relatedness within the left inferior frontal gyrus and the posterior portion of the left superior/middle temporal gyrus. We suggest that together these two regions mediated the suppression of unfulfilled semantic predictions and lexico-semantic processing of unrelated targets that were inconsistent with these predictions. Moreover, under conditions of higher (versus lower) predictive validity, a functional connectivity analysis showed that the left inferior frontal and left posterior superior/middle temporal gyrus were more tightly interconnected with one another, as well as with the left anterior cingulate cortex. The left anterior cingulate cortex was, in turn, more tightly connected to superior lateral frontal cortices and subcortical regions-a network that mediates rapid learning and adaptation and that may have played a role in switching to a more predictive mode of processing in response to the statistical structure of the wider environmental context. Together, these findings highlight close links between the networks mediating semantic prediction, executive function and learning, giving new insights into how our brains are able to flexibly adapt to our environment.


Asunto(s)
Corteza Prefrontal/fisiología , Lóbulo Temporal/fisiología , Adulto , Mapeo Encefálico/métodos , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Semántica , Yin-Yang , Adulto Joven
18.
Brain Connect ; 6(4): 345-55, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26746708

RESUMEN

When we learn a second language later in life, do we integrate it with the established neural networks in place for the first language or is at least a partially new network recruited? While there is evidence that simple grammatical structures in a second language share a system with the native language, the story becomes more multifaceted for complex sentence structures. In this study, we investigated the underlying brain networks in native speakers compared with proficient second language users while processing complex sentences. As hypothesized, complex structures were processed by the same large-scale inferior frontal and middle temporal language networks of the brain in the second language, as seen in native speakers. These effects were seen both in activations and task-related connectivity patterns. Furthermore, the second language users showed increased task-related connectivity from inferior frontal to inferior parietal regions of the brain, regions related to attention and cognitive control, suggesting less automatic processing for these structures in a second language.


Asunto(s)
Red Nerviosa/fisiología , Percepción del Habla/fisiología , Adulto , Atención/fisiología , Encéfalo/fisiología , Mapeo Encefálico/métodos , Femenino , Humanos , Lenguaje , Aprendizaje/fisiología , Imagen por Resonancia Magnética , Masculino , Lóbulo Parietal/fisiología , Lóbulo Temporal/fisiología
19.
Cereb Cortex ; 26(4): 1377-87, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25316341

RESUMEN

Although there is broad agreement that top-down expectations can facilitate lexical-semantic processing, the mechanisms driving these effects are still unclear. In particular, while previous electroencephalography (EEG) research has demonstrated a reduction in the N400 response to words in a supportive context, it is often challenging to dissociate facilitation due to bottom-up spreading activation from facilitation due to top-down expectations. The goal of the current study was to specifically determine the cortical areas associated with facilitation due to top-down prediction, using magnetoencephalography (MEG) recordings supplemented by EEG and functional magnetic resonance imaging (fMRI) in a semantic priming paradigm. In order to modulate expectation processes while holding context constant, we manipulated the proportion of related pairs across 2 blocks (10 and 50% related). Event-related potential results demonstrated a larger N400 reduction when a related word was predicted, and MEG source localization of activity in this time-window (350-450 ms) localized the differential responses to left anterior temporal cortex. fMRI data from the same participants support the MEG localization, showing contextual facilitation in left anterior superior temporal gyrus for the high expectation block only. Together, these results provide strong evidence that facilitatory effects of lexical-semantic prediction on the electrophysiological response 350-450 ms postonset reflect modulation of activity in left anterior temporal cortex.


Asunto(s)
Semántica , Lóbulo Temporal/fisiología , Adolescente , Adulto , Mapeo Encefálico , Electroencefalografía , Potenciales Evocados , Femenino , Lateralidad Funcional , Humanos , Imagen por Resonancia Magnética , Magnetoencefalografía , Masculino , Lectura , Procesamiento de Señales Asistido por Computador , Adulto Joven
20.
Neuropsychologia ; 76: 79-91, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25858603

RESUMEN

In using language, people not only exchange information, but also navigate their social world - for example, they can express themselves indirectly to avoid losing face. In this functional magnetic resonance imaging study, we investigated the neural correlates of interpreting face-saving indirect replies, in a situation where participants only overheard the replies as part of a conversation between two other people, as well as in a situation where the participants were directly addressed themselves. We created a fictional job interview context where indirect replies serve as a natural communicative strategy to attenuate one's shortcomings, and asked fMRI participants to either pose scripted questions and receive answers from three putative job candidates (addressee condition) or to listen to someone else interview the same candidates (overhearer condition). In both cases, the need to evaluate the candidate ensured that participants had an active interest in comprehending the replies. Relative to direct replies, face-saving indirect replies increased activation in medial prefrontal cortex, bilateral temporo-parietal junction (TPJ), bilateral inferior frontal gyrus and bilateral middle temporal gyrus, in active overhearers and active addressees alike, with similar effect size, and comparable to findings obtained in an earlier passive listening study (Basnáková et al., 2014). In contrast, indirectness effects in bilateral anterior insula and pregenual ACC, two regions implicated in emotional salience and empathy, were reliably stronger in addressees than in active overhearers. Our findings indicate that understanding face-saving indirect language requires additional cognitive perspective-taking and other discourse-relevant cognitive processing, to a comparable extent in active overhearers and addressees. Furthermore, they indicate that face-saving indirect language draws upon affective systems more in addressees than in overhearers, presumably because the addressee is the one being managed by a face-saving reply. In all, face-saving indirectness provides a window on the cognitive as well as affect-related neural systems involved in human communication.


Asunto(s)
Encéfalo/fisiología , Comunicación , Comprensión/fisiología , Percepción Social , Percepción del Habla/fisiología , Adulto , Mapeo Encefálico , Femenino , Humanos , Relaciones Interpersonales , Imagen por Resonancia Magnética , Masculino , Adulto Joven
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