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1.
J Med Internet Res ; 22(8): e20186, 2020 08 06.
Artículo en Inglés | MEDLINE | ID: mdl-32701459

RESUMEN

BACKGROUND: Social and physical distancing in response to the coronavirus disease (COVID-19) pandemic has made screen-mediated information and communication technologies (media) indispensable. Whether an increase in screen use is a source of or a relief for stress remains to be seen. OBJECTIVE: In the immediate aftermath of the COVID-19 lockdowns, we investigated the relation between subjective stress and changes in the pattern of media use. Based on Lazarus's transactional model of appraisal and coping, and building on an earlier similar survey, we hypothesize that individual differences in the appraisal of media predict variations in approach or avoidance of media for coping with COVID-19 stress. METHODS: Between March 20 and April 20, 2020, a brief snowball survey entitled: "What media helps, what media hurts: coping with COVID19 through screens" was distributed via Concordia University's mailing lists and social media (PERFORM Centre, EngAGE Centre, and Media Health Lab). Using a media repertoire method, we asked questions about preferences, changes in use, and personal appraisal of media experiences (approach, avoid, and ignore) as a result of the COVID-19 pandemic and investigated interindividual differences in media use by factors such as subjective stress, age, gender, and self-reported mental health. RESULTS: More than 90% of the survey respondents were in Canada and the east coast of the United States. From 685 completed responses, 169 respondents were "very stressed" and 452 were "slightly worried" about the pandemic. COVID-19 stress led to increased use of Facebook (χ23=11.76, P=.008), television (χ23=12.40, P=.006), YouTube (χ23=8.577, P=.04), and streaming services such as Netflix (χ23=10.71, P=.01). Respondents who considered their mental health "not good" were twice as likely to prefer streaming services as a coping tool for self-isolation. Women and nonbinary respondents were twice as likely than men to pick social media for coping. Individuals younger than 35 years were 3 times more likely to pick computer games, and individuals older than 55 years were more likely to pick network television or print media. Gender affected the appraisal of media (less in men than others) in terms of avoid (F1,637=5.84, P=.02) and approach scores (F1,637=14.31, P<.001). Subjective mental health affected the ignore score (less in those who said "good" than others; F1,637=13.88, P<.001). The appraisal score and use increase explained variations in worrying about physical and mental health stress due to increased screen time. A qualitative analysis of open-ended questions revealed that media (especially social networks) were important for coping if they provided support and connection through the dissemination of factual and positive information while avoiding the overflow of sensational and false news. CONCLUSIONS: The relationship between appraisal of media's positive and negative facets vary with demographic differences in mental health resiliency. The media repertoire approach is an important tool in studies that focus on assessing the benefits and harms of screen overuse in different populations, especially in the context of the COVID-19 pandemic.


Asunto(s)
Adaptación Psicológica , Infecciones por Coronavirus/epidemiología , Medios de Comunicación de Masas/estadística & datos numéricos , Salud Mental/estadística & datos numéricos , Modelos Psicológicos , Neumonía Viral/epidemiología , Medios de Comunicación Sociales/estadística & datos numéricos , Encuestas y Cuestionarios , Adulto , Betacoronavirus , COVID-19 , Ejercicio Físico/psicología , Femenino , Mapeo Geográfico , Humanos , Masculino , Persona de Mediana Edad , Pandemias , SARS-CoV-2 , Tiempo de Pantalla , Red Social , Televisión/estadística & datos numéricos , Juegos de Video/estadística & datos numéricos , Adulto Joven
2.
J Med Internet Res ; 21(4): e11485, 2019 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-30938685

RESUMEN

BACKGROUND: The relationship between stress and screen addiction is often studied by exploring a single aspect of screen-related behavior in terms of maladaptive dependency or the risks associated with the content. Generally, little attention is given to the pattern of using different screens for different types of stressors, and variations arising from the subjective perception of stress and screen addiction are often neglected. Given that both addiction and stress are complex and multidimensional factors, we performed a multivariate analysis of the link between individual's subjective perceptions of screen addiction, various types of stress, and the pattern of screen usage. OBJECTIVE: Using the media-repertoires framework to study usage patterns, we explored (1) the relation between subjective and quantitative assessments of stress and screen addiction; and (2) differences in stress types in relation to subjective screen addiction and different types of needs for screens. We hypothesized that interindividual heterogeneity in screen-related behavior would reflect coping differences in dealing with different stressors. METHODS: A multifactorial Web-based survey was conducted to gather data about screen-related behaviors (such as screen time, internet addiction, and salience of different types of screens and related activities), and different sources of stress (emotional states, perceptual risks, health problems, and general life domain satisfaction). We performed group comparisons based on whether participants reported themselves as addicted to internet and games (A1) or not (A0), and whether they had experienced a major life stress (S1) or not (S0). RESULTS: Complete responses were obtained in 459 out of 654 survey responders, with the majority in the S1A0 (44.6%, 205/459) group, followed by S0A0 (25.9%, 119/459), S1A1 (19.8%, 91/459), and S0A1 (9.5%, 44/459). The S1A1 group was significantly different from S0A0 in all types of stress, internet overuse, and screen time (P<.001). Groups did not differ in rating screens important for short message service (SMS) or mail, searching information, shopping, and following the news, but a greater majority of A1 depended on screens for entertainment (χ23=20.5; P<.001), gaming (χ23=35.6; P<.001), and social networking (χ23=26.5; P<.001). Those who depended on screens for entertainment and social networking had up to 19% more emotional stress and up to 14% more perceptual stress. In contrast, those who relied on screens for work and professional networking had up to 10% higher levels of life satisfaction. Regression models including age, gender, and 4 stress types explained less than 30% of variation in internet use and less than 24% of the likelihood of being screen addicted. CONCLUSIONS: We showed a robust but heterogeneous link between screen dependency and emotional and perceptual stressors that shift the pattern of screen usage toward entertainment and social networking. Our findings underline the potential of using ludic and interactive apps for intervention against stress.


Asunto(s)
Conducta Adictiva/psicología , Internet/tendencias , Red Social , Adaptación Psicológica , Adulto , Estudios Transversales , Femenino , Humanos , Masculino , Encuestas y Cuestionarios
3.
Hum Brain Mapp ; 38(4): 2276-2325, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28145075

RESUMEN

A decade of research and development in resting-state functional MRI (RSfMRI) has opened new translational and clinical research frontiers. This review aims to bridge between technical and clinical researchers who seek reliable neuroimaging biomarkers for studying drug interactions with the brain. About 85 pharma-RSfMRI studies using BOLD signal (75% of all) or arterial spin labeling (ASL) were surveyed to investigate the acute effects of psychoactive drugs. Experimental designs and objectives include drug fingerprinting dose-response evaluation, biomarker validation and calibration, and translational studies. Common biomarkers in these studies include functional connectivity, graph metrics, cerebral blood flow and the amplitude and spectrum of BOLD fluctuations. Overall, RSfMRI-derived biomarkers seem to be sensitive to spatiotemporal dynamics of drug interactions with the brain. However, drugs cause both central and peripheral effects, thus exacerbate difficulties related to biological confounds, structured noise from motion and physiological confounds, as well as modeling and inference testing. Currently, these issues are not well explored, and heterogeneities in experimental design, data acquisition and preprocessing make comparative or meta-analysis of existing reports impossible. A unifying collaborative framework for data-sharing and data-mining is thus necessary for investigating the commonalities and differences in biomarker sensitivity and specificity, and establishing guidelines. Multimodal datasets including sham-placebo or active control sessions and repeated measurements of various psychometric, physiological, metabolic and neuroimaging phenotypes are essential for pharmacokinetic/pharmacodynamic modeling and interpretation of the findings. We provide a list of basic minimum and advanced options that can be considered in design and analyses of future pharma-RSfMRI studies. Hum Brain Mapp 38:2276-2325, 2017. © 2017 Wiley Periodicals, Inc.


Asunto(s)
Investigación Biomédica , Química Encefálica , Encéfalo , Imagen por Resonancia Magnética , Animales , Encéfalo/diagnóstico por imagen , Encéfalo/efectos de los fármacos , Encéfalo/fisiología , Mapeo Encefálico , Circulación Cerebrovascular/efectos de los fármacos , Humanos , Procesamiento de Imagen Asistido por Computador , Descanso , Marcadores de Spin , Investigación Biomédica Traslacional
4.
Neuroimage ; 124(Pt B): 1188-1195, 2016 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-26364860

RESUMEN

Neuroimaging has been facing a data deluge characterized by the exponential growth of both raw and processed data. As a result, mining the massive quantities of digital data collected in these studies offers unprecedented opportunities and has become paramount for today's research. As the neuroimaging community enters the world of "Big Data", there has been a concerted push for enhanced sharing initiatives, whether within a multisite study, across studies, or federated and shared publicly. This article will focus on the database and processing ecosystem developed at the Montreal Neurological Institute (MNI) to support multicenter data acquisition both nationally and internationally, create database repositories, facilitate data-sharing initiatives, and leverage existing software toolkits for large-scale data processing.


Asunto(s)
Bases de Datos Factuales , Difusión de la Información , Neuroimagen , Conducta , Genómica , Humanos , Estudios Longitudinales , Control de Calidad , Programas Informáticos
5.
Neuroimage ; 122: 440-50, 2015 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-26277774

RESUMEN

The serotonergic system is widely distributed throughout the central nervous system. It is well known as a mood regulating system, although it also contributes to many other functions. With resting state functional magnetic resonance imaging (RS-fMRI) it is possible to investigate whole brain functional connectivity. We used this non-invasive neuroimaging technique to measure acute pharmacological effects of the selective serotonin reuptake inhibitor sertraline (75 mg) in 12 healthy volunteers. In this randomized, double blind, placebo-controlled, crossover study, RS-fMRI scans were repeatedly acquired during both visits (at baseline and 3, 5, 7 and 9h after administering sertraline or placebo). Within-group comparisons of voxelwise functional connectivity with ten functional networks were examined (p<0.005, corrected) using a mixed effects model with cerebrospinal fluid, white matter, motion parameters, heart rate and respiration as covariates. Sertraline induced widespread effects on functional connectivity with multiple networks; the default mode network, the executive control network, visual networks, the sensorimotor network and the auditory network. A common factor among these networks was the involvement of the precuneus and posterior cingulate cortex. Cognitive and subjective measures were taken as well, but yielded no significant treatment effects, emphasizing the sensitivity of RS-fMRI to pharmacological challenges. The results are consistent with the existence of an extensive serotonergic system relating to multiple brain functions with a possible key role for the precuneus and cingulate.


Asunto(s)
Encéfalo/fisiología , Serotonina/fisiología , Adulto , Encéfalo/efectos de los fármacos , Mapeo Encefálico , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Hidrocortisona/sangre , Imagen por Resonancia Magnética , Masculino , Pruebas Neuropsicológicas , Prolactina/sangre , Inhibidores Selectivos de la Recaptación de Serotonina/farmacocinética , Inhibidores Selectivos de la Recaptación de Serotonina/farmacología , Sertralina/farmacocinética , Sertralina/farmacología , Adulto Joven
6.
Neuroimage ; 108: 396-409, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25554429

RESUMEN

Ketamine, an NMDA receptor antagonist, is increasingly used to study the link between glutamatergic signaling dysregulation and mood and chronic pain disorders. Glutamatergic neurotransmission and stress corticosteroids (cortisol in human) are critical for Ca(2+) mediated neuroplasticity and behavioral adaptation. The mechanisms of action of glutamatergic neurotransmission and stress corticosteroids on the NMDA-receptors of the hippocampus have been long investigated in animals, but given little attention in human studies. In this randomized single-blinded placebo-controlled crossover study (12 healthy young men), five sets of resting-state fMRI (RSFMRI), pseudocontinuous arterial spin labeling (PCASL), and corresponding salivary cortisol samples were acquired over 4h, at given intervals under pharmacokinetically-controlled infusion of subanesthetic ketamine (20 & 40mg/70kg/h). An identical procedure was repeated under a sham placebo condition. Differences in the profile of ketamine versus placebo effect over time were examined. Compared to placebo, ketamine mimicked a stress-like response (increased cortisol, reduced calmness and alertness, and impaired working memory). Ketamine effects on the brain included a transient prefrontal hyperperfusion and a dose-related reduction of relative hippocampal perfusion, plus emerging hyperconnectivity between the hippocampus and the occipital, cingulate, precuneal, cerebellar and basal ganglia regions. The spatiotemporal profiles of ketamine effects on different hippocampal subnetworks suggest a topographically dissociable change in corticohippocampal functional connectivity. We discuss our findings in the context of the negative feedback inhibition theory of the hippocampal stress-control. This pilot study provides a methodological framework for multimodal functional neuroimaging under resting-state conditions, which may be generalized for translational studies of glutamatergic- or stress-related etiology of neuropsychiatric disorders.


Asunto(s)
Encéfalo/fisiología , Ketamina/farmacología , Imagen por Resonancia Magnética , Marcadores de Spin , Estrés Psicológico/fisiopatología , Adulto , Biomarcadores/análisis , Encéfalo/efectos de los fármacos , Estudios Cruzados , Hipocampo/efectos de los fármacos , Hipocampo/fisiología , Humanos , Hidrocortisona/análisis , Masculino , Proyectos Piloto , Descanso , Saliva/química , Método Simple Ciego , Adulto Joven
7.
Hum Brain Mapp ; 35(3): 929-42, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23281174

RESUMEN

Resting state fMRI (RSfMRI) and arterial spin labeling (ASL) provide the field of pharmacological Neuroimaging tool for investigating states of brain activity in terms of functional connectivity or cerebral blood flow (CBF). Functional connectivity reflects the degree of synchrony or correlation of spontaneous fluctuations--mostly in the blood oxygen level dependent (BOLD) signal--across brain networks; but CBF reflects mean delivery of arterial blood to the brain tissue over time. The BOLD and CBF signals are linked to common neurovascular and hemodynamic mechanisms that necessitate increased oxygen transportation to the site of neuronal activation; however, the scale and the sources of variation in static CBF and spatiotemporal BOLD correlations are likely different. We tested this hypothesis by examining the relation between CBF and resting-state-network consistency (RSNC)--representing average intranetwork connectivity, determined from dual regression analysis with eight standard networks of interest (NOIs)--in a crossover placebo-controlled study of morphine and alcohol. Overall, we observed spatially heterogeneous relations between RSNC and CBF, and between the experimental factors (drug-by-time, time, drug and physiological rates) and each of these metrics. The drug-by-time effects on CBF were significant in all networks, but significant RSNC changes were limited to the sensorimotor, the executive/salience and the working memory networks. The post-hoc voxel-wise statistics revealed similar dissociations, perhaps suggesting differential sensitivity of RSNC and CBF to neuronal and vascular endpoints of drug actions. The spatial heterogeneity of RSNC/CBF relations encourages further investigation into the role of neuroreceptor distribution and cerebrovascular anatomy in predicting spontaneous fluctuations under drugs.


Asunto(s)
Encéfalo/irrigación sanguínea , Encéfalo/fisiología , Conectoma/métodos , Imagen por Resonancia Magnética/métodos , Red Nerviosa/fisiología , Adolescente , Adulto , Analgésicos Opioides/administración & dosificación , Analgésicos Opioides/sangre , Analgésicos Opioides/farmacocinética , Encéfalo/efectos de los fármacos , Pruebas Respiratorias , Depresores del Sistema Nervioso Central/administración & dosificación , Depresores del Sistema Nervioso Central/sangre , Depresores del Sistema Nervioso Central/farmacocinética , Circulación Cerebrovascular/efectos de los fármacos , Circulación Cerebrovascular/fisiología , Estudios Cruzados , Método Doble Ciego , Etanol/administración & dosificación , Etanol/sangre , Etanol/farmacocinética , Humanos , Masculino , Morfina/administración & dosificación , Morfina/sangre , Morfina/farmacocinética , Red Nerviosa/efectos de los fármacos , Placebos , Descanso/fisiología , Marcadores de Spin , Adulto Joven
8.
Neuroimage ; 65: 499-510, 2013 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-23022093

RESUMEN

Growing interest in pharmacological resting state fMRI (RSfMRI) necessitates developing standardized and robust analytical approaches that are insensitive to spurious correlated physiological signals. However, in pharmacological experiments physiological variations constitute an important aspect of the pharmacodynamic/pharmacokinetic profile of drug action; therefore retrospective corrective methods that discard physiological signals as noise may not be suitable. Previously, we have shown that template-based dual regression analysis is a sensitive method for model-free and objective detection of drug-specific effects on functional brain connectivity. In the current study, the robustness of this standard approach to physiological variations in a placebo controlled, repeated measures pharmacological RSfMRI study of morphine and alcohol in 12 healthy young men is tested. The impact of physiology-related variations on statistical inferences has been studied by: 1) modeling average physiological rates in higher level group analysis; 2) Regressing out the instantaneous respiration variation (RV); 3) applying retrospective image correction (RETROICOR) in the preprocessing stage; and 4) performing combined RV and heart rate correction (RVHRCOR) by regressing out physiological pulses convolved with canonical respiratory and cardiac hemodynamic response functions. Results indicate regional sensitivity of the BOLD signal to physiological variations, especially in the vicinity of large vessels, plus certain brain structures that are reported to be involved in physiological regulation, such as posterior cingulate, precuneus, medial prefrontal and insular cortices, as well as the thalamus, cerebellum and the brainstem. The largest impact of "correction" on final statistical test outcomes resulted from including the average respiration frequency and heart rate in the higher-level group analysis. Overall, the template-based dual regression method seems robust against physical noise that is corrected by RV regression or RETROICOR. However, convolving the RV and HR with canonical hemodynamic response functions caused a notable change in the BOLD signal variance, and in resting state connectivity estimates. The impact of RVHRCOR on statistical tests was limited to elimination of both morphine and alcohol effects related to the somatosensory network that consists of insula and cingulate cortex-important structures for autonomic regulation. Although our data do not warrant speculations about neuronal or vascular origins of these effects, these observations raise caution about the implications of physiological 'noise' and the risks of introducing false positives (e.g. increased white matter connectivity) by using generalized physiological correction methods in pharmacological studies. The obvious sensitivity of the posterior part of the default mode network to different correction schemes, underlines the importance of controlling for physiological fluctuations in seed-based functional connectivity analyses.


Asunto(s)
Artefactos , Encéfalo/fisiología , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Vías Nerviosas/fisiología , Adolescente , Adulto , Encéfalo/efectos de los fármacos , Mapeo Encefálico/métodos , Depresores del Sistema Nervioso Central/farmacocinética , Depresores del Sistema Nervioso Central/farmacología , Método Doble Ciego , Etanol/farmacocinética , Etanol/farmacología , Humanos , Masculino , Morfina/farmacocinética , Morfina/farmacología , Narcóticos/farmacocinética , Narcóticos/farmacología , Vías Nerviosas/efectos de los fármacos , Respiración/efectos de los fármacos , Descanso , Adulto Joven
9.
Front Neuroinform ; 17: 1251023, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37841811

RESUMEN

Neuroimaging research requires sophisticated tools for analyzing complex data, but efficiently leveraging these tools can be a major challenge, especially on large datasets. CBRAIN is a web-based platform designed to simplify the use and accessibility of neuroimaging research tools for large-scale, collaborative studies. In this paper, we describe how CBRAIN's unique features and infrastructure were leveraged to integrate TAPAS PhysIO, an open-source MATLAB toolbox for physiological noise modeling in fMRI data. This case study highlights three key elements of CBRAIN's infrastructure that enable streamlined, multimodal tool integration: a user-friendly GUI, a Brain Imaging Data Structure (BIDS) data-entry schema, and convenient in-browser visualization of results. By incorporating PhysIO into CBRAIN, we achieved significant improvements in the speed, ease of use, and scalability of physiological preprocessing. Researchers now have access to a uniform and intuitive interface for analyzing data, which facilitates remote and collaborative evaluation of results. With these improvements, CBRAIN aims to become an essential open-science tool for integrative neuroimaging research, supporting FAIR principles and enabling efficient workflows for complex analysis pipelines.

10.
Front Psychol ; 14: 1063146, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37034933

RESUMEN

Older adults are at a higher risk of loneliness, compared to other demographics. The use of Internet Communication and Technologies (ICTs) among older adults is steadily increasing and given ICTs provide a means of enhancing social connectedness suggests they may have positive effects on reducing loneliness. Therefore, the aim of this scoping review was to examine the research that explores how ICTs may be implicated in mitigating loneliness and increasing social connectedness among older adults. After the examination of 54 articles, we identified three major themes within the literature: (1) ICTs were associated with a reduction in loneliness and increase in wellbeing. (2) ICTs promoted social connectedness by facilitating conversations. (3) Factors such as training, self-efficacy, self-esteem, autonomy, and the design/features, or affordances, of ICTs contribute toward the associations between ICT use and wellbeing. The heterogeneity of methodologies, statistical reporting, the small sample sizes of interventional and observational studies, and the diversity of the experimental contexts underline the challenges of quantitative research in this field and highlights the necessity of tailoring ICT interventions to the needs and contexts of the older users.

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