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1.
Cereb Cortex ; 33(8): 4384-4404, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36130104

RESUMO

A fronto-temporal brain network has long been implicated in language comprehension. However, this network's role in language production remains debated. In particular, it remains unclear whether all or only some language regions contribute to production, and which aspects of production these regions support. Across 3 functional magnetic resonance imaging experiments that rely on robust individual-subject analyses, we characterize the language network's response to high-level production demands. We report 3 novel results. First, sentence production, spoken or typed, elicits a strong response throughout the language network. Second, the language network responds to both phrase-structure building and lexical access demands, although the response to phrase-structure building is stronger and more spatially extensive, present in every language region. Finally, contra some proposals, we find no evidence of brain regions-within or outside the language network-that selectively support phrase-structure building in production relative to comprehension. Instead, all language regions respond more strongly during production than comprehension, suggesting that production incurs a greater cost for the language network. Together, these results align with the idea that language comprehension and production draw on the same knowledge representations, which are stored in a distributed manner within the language-selective network and are used to both interpret and generate linguistic utterances.


Assuntos
Mapeamento Encefálico , Imageamento por Ressonância Magnética , Imageamento por Ressonância Magnética/métodos , Mapeamento Encefálico/métodos , Idioma , Encéfalo/fisiologia , Compreensão/fisiologia
2.
Matern Child Nutr ; 18(4): e13390, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35712809

RESUMO

To evaluate the relationship between infant age of egg introduction and malnutrition-related growth outcomes in the United States, we analysed secondary data of 1716 mother-child dyads in the Infant Feeding Practices Study II and its Year 6 Follow-Up Study. Malnutrition-related growth outcomes included body mass index z-score (BMIZ), obesity (weight-for-height z-score [WHZ] ≥3 or BMIZ ≥ 2), WHZ, wasting (WHZ < -2), height-for-age z-score (HAZ), and stunting (HAZ < -2). Infant age at egg introduction was analysed as a continuous variable. We used generalised estimating equations to estimate the mean difference in continuous outcomes and relative risk [RR]) for binary outcomes, adjusting for related maternal and child confounders. We also explored interactions with child sex, maternal race/ethnicity, maternal educational level, ever breastfeeding, and formula feeding. In the total sample, a later infant age at egg introduction was associated with a lower mean difference in HAZ (confounder-adjusted mean difference = -0.08, 95% confidence interval [CI]: -0.12 to -0.03 per month) and a higher risk of stunting (confounder-adjusted RR = 1.17, 95% CI: 1.03-1.33 per month) at 6 years. The associations between infant age at egg introduction and 12-month growth outcomes differed by child sex. Among females but not among males, later introduction of eggs was associated with a lower mean WHZ (-0.06 [-0.12 to 0.00] per month) at 12 months. Later egg introduction during infancy was associated with a lower mean HAZ and a higher risk of stunting in 6-year-old children. Besides this, it was associated with a lower WHZ among females at 12 months.


Assuntos
Desnutrição , Estatura , Peso Corporal , Criança , Feminino , Seguimentos , Transtornos do Crescimento/complicações , Transtornos do Crescimento/epidemiologia , Humanos , Lactente , Masculino , Desnutrição/complicações , Desnutrição/epidemiologia , Estados Unidos/epidemiologia
3.
bioRxiv ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38798360

RESUMO

Left hemisphere damage in adulthood often leads to linguistic deficits, but many cases of early damage leave linguistic processing preserved, and a functional language system can develop in the right hemisphere. To explain this early apparent equipotentiality of the two hemispheres for language, some have proposed that the language system is bilateral during early development and only becomes left-lateralized with age. We examined language lateralization using functional magnetic resonance imaging with two large pediatric cohorts (total n=273 children ages 4-16; n=107 adults). Strong, adult-level left-hemispheric lateralization (in activation volume and response magnitude) was evident by age 4. Thus, although the right hemisphere can take over language function in some cases of early brain damage, and although some features of the language system do show protracted development (magnitude of language response and strength of inter-regional correlations in the language network), the left-hemisphere bias for language is robustly present by 4 years of age. These results call for alternative accounts of early equipotentiality of the two hemispheres for language.

4.
Neuropsychologia ; 169: 108184, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35183561

RESUMO

Language processing relies on a left-lateralized fronto-temporal brain network. How this network emerges ontogenetically remains debated. We asked whether frontal language areas emerge in the absence of temporal language areas through a 'deep-data' investigation of an individual (EG) born without her left temporal lobe. Using fMRI methods that have been validated to elicit reliable individual-level responses, we find that-as expected for early left-hemisphere damage-EG has a fully functional language network in her right hemisphere (comparable to the LH network in n = 145 controls) and intact linguistic abilities. However, we detect no response to language in EG's left frontal lobe (replicated across two sessions, 3 years apart). Another network-the multiple demand network-is robustly present in frontal lobes bilaterally, suggesting that EG's left frontal cortex can support non-linguistic cognition. The existence of temporal language areas therefore appears to be a prerequisite for the emergence of the frontal language areas.


Assuntos
Mapeamento Encefálico , Idioma , Mapeamento Encefálico/métodos , Feminino , Lobo Frontal/fisiologia , Lateralidade Funcional/fisiologia , Humanos , Imageamento por Ressonância Magnética/métodos , Lobo Temporal/fisiologia
5.
Sci Data ; 9(1): 529, 2022 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-36038572

RESUMO

Two analytic traditions characterize fMRI language research. One relies on averaging activations across individuals. This approach has limitations: because of inter-individual variability in the locations of language areas, any given voxel/vertex in a common brain space is part of the language network in some individuals but in others, may belong to a distinct network. An alternative approach relies on identifying language areas in each individual using a functional 'localizer'. Because of its greater sensitivity, functional resolution, and interpretability, functional localization is gaining popularity, but it is not always feasible, and cannot be applied retroactively to past studies. To bridge these disjoint approaches, we created a probabilistic functional atlas using fMRI data for an extensively validated language localizer in 806 individuals. This atlas enables estimating the probability that any given location in a common space belongs to the language network, and thus can help interpret group-level activation peaks and lesion locations, or select voxels/electrodes for analysis. More meaningful comparisons of findings across studies should increase robustness and replicability in language research.


Assuntos
Encéfalo , Idioma , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Mapeamento Encefálico , Humanos
6.
J Gen Physiol ; 150(11): 1583-1593, 2018 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-30266757

RESUMO

Action potentials (APs) are the functional units of fast electrical signaling in excitable cells. The upstroke and downstroke of an AP is generated by the competing and asynchronous action of Na+- and K+-selective voltage-gated conductances. Although a mixture of voltage-gated channels has been long recognized to contribute to the generation and temporal characteristics of the AP, understanding how each of these proteins function and are regulated during electrical signaling remains the subject of intense research. AP properties vary among different cellular types because of the expression diversity, subcellular location, and modulation of ion channels. These complexities, in addition to the functional coupling of these proteins by membrane potential, make it challenging to understand the roles of different channels in initiating and "temporally shaping" the AP. Here, to address this problem, we focus our efforts on finding conditions that allow reliable AP recordings from Xenopus laevis oocytes coexpressing Na+ and K+ channels. As a proof of principle, we show how the expression of a variety of K+ channel subtypes can modulate excitability in this minimal model system. This approach raises the prospect of studies on the modulation of APs by pharmacological or biological means with a controlled background of Na+ and K+ channel expression.


Assuntos
Potenciais de Ação , Modelos Animais , Técnicas de Patch-Clamp , Xenopus , Animais , Oócitos/metabolismo , Potássio/metabolismo , Sódio/metabolismo
7.
JMIR Ment Health ; 4(4): e46, 2017 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-29066426

RESUMO

BACKGROUND: Web-based typed exchanges are increasingly used by professionals to provide emotional support to patients. Although some empirical evidence exists to suggest that various strategies may be used to convey emotion during Web-based text communication, there has been no critical review of these data in patients with chronic conditions. OBJECTIVES: The objective of this review was to identify the techniques used to convey emotion in written or typed Web-based communication and assess the empirical evidence regarding impact on communication and psychological outcomes. METHODS: An electronic search of databases, including MEDLINE, CINAHL, PsycINFO, EMBASE, and the Cochrane Library was conducted to identify literature published from 1990 to 2016. Searches were also conducted using Google Scholar, manual searching of reference lists of identified papers and manual searching of tables of contents for selected relevant journals. Data extraction and coding were completed by 2 reviewers (10.00% [573/5731] of screened papers, at abstract/title screening stage; 10.0% of screened [69/694] papers, at full-text screening stage). Publications were assessed against the eligibility criteria and excluded if they were duplicates, were not published in English, were published before 1990, referenced animal or nonhuman subjects, did not describe original research, were not journal papers, or did not empirically test the effect of one or more nonverbal communication techniques (for eg, smileys, emoticons, emotional bracketing, voice accentuation, trailers [ellipsis], and pseudowords) as part of Web-based or typed communication on communication-related variables, including message interpretation, social presence, the nature of the interaction (eg, therapeutic alliance), patient perceptions of the interaction (eg, participant satisfaction), or psychological outcomes, including depression, anxiety, and distress. RESULTS: A total of 6902 unique publications were identified. Of these, six publications met the eligibility criteria and were included in a narrative synthesis. All six studies addressed the effect of smileys or emoticons on participant responses, message interpretation, or social presence of the writer. None of these studies specifically targeted chronic conditions. It was found that emoticons were more effective in influencing the emotional impact of a message than no cue and that smileys and emoticons were able to convey a limited amount of emotion. No studies addressed other techniques for conveying emotion in written communication. No studies addressed the effects of any techniques on the nature of the interaction (eg, therapeutic alliance), patient perceptions of the interaction (eg, participant satisfaction), or psychological outcomes (depression, anxiety, or distress). CONCLUSIONS: There is a need for greater empirical attention to the effects of the various proposed techniques for conveying emotion in Web-based typed communications to inform health service providers regarding best-practice communication skills in this setting.

8.
Crit Rev Oncol Hematol ; 97: 247-62, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26412718

RESUMO

To conduct a comprehensive review to examine among hematological cancer patients: (1) rates of adherence to self-administered cancer treatments; and (2) factors impacting on their adherence. Fifty two eligible publications were identified. The majority focused on Chronic Myeloid Leukaemia (CML) (n=40) and Acute Lymphoid Leukaemia (ALL) (n=11) patients. Adherence rates varied and depended on the definition and measures used. Patient understanding about their disease and treatment, and forgetting to take their medication impacted on patients' level of adherence; while the use of reminders reduced forgetfulness. There is a lack of valid and reliable information relating to medication adherence of hematological cancer patients. Based on the limited data available we provide a profile of CML and ALL patients at potential risk of medication non-adherence, as well as a proposed checklist that can be used by health care providers in assessing and supporting patients in adhering to their medication.


Assuntos
Neoplasias Hematológicas/tratamento farmacológico , Adesão à Medicação , Antineoplásicos/uso terapêutico , Humanos
9.
Br J Gen Pract ; 64(620): e122-7, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24567650

RESUMO

BACKGROUND: General practice is a common setting for the provision of weight-management advice, as well as the treatment of depression. While there is some evidence of a reciprocal relationship between obesity and depression, there are limited data about the rates of depression among general practice patients who are underweight, normal weight, overweight, and obese. AIM To explore the prevalence of depression among underweight, normal weight, overweight, and obese general practice patients. DESIGN AND SETTING: A cross-sectional survey was conducted in 12 Australian general practices. METHOD Patients aged ≥18 years and older who were presenting for general practice care were eligible to participate. Consenting patients completed a touchscreen computer survey assessing self-reported weight and height. Depression was assessed by the Patient Health Questionnaire-9 (PHQ-9), with a score of ≥10 used to indicate possible depression. RESULTS: Data were obtained from 3361 participants. The prevalence of depression was 24% (95% confidence interval [CI] = 11.86 to 39.28) among underweight participants, 11% (95% CI = 8.5 to 14.0) among normal weight participants, 12% (95% CI = 0.9 to 15.2) among overweight participants, and 23% (95% CI = 17.8 to 29.0) among obese participants. The prevalence of depression was higher for women than for men across all weight categories except underweight. CONCLUSION: Weight and depression demonstrated a U-shaped relationship, with higher prevalence of depression observed among underweight and obese general practice patients. These conditions may act as red flags for opportunistic screening of depression in the general practice setting.


Assuntos
Depressão/epidemiologia , Medicina Geral , Obesidade/epidemiologia , Magreza/epidemiologia , Adolescente , Adulto , Austrália/epidemiologia , Índice de Massa Corporal , Comorbidade , Estudos Transversais , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Autorrelato , Inquéritos e Questionários
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