Medical Express

ISSN (print): 2318-8111

ISSN (online): 2358-0429

Author's Articles

9 result(s) for: Sérgio Machado

Social networking, a new online addiction: a review of Facebook and other addiction disorders

Eduardo Guedes; Antonio Egidio Nardi; Flávia Melo Campos Leite Guimarães; Sergio Machado; Anna Lucia Spear King


Abstract PDF

INTRODUCTION: Facebook is the world's most widely accessed social network, where millions of people intercommunicate. Behavioral and psychological changes relate to abusive and uncontrolled use creating severe impacts on users' life.
METHOD: A critical revision was performed through MedLine, Lilacs, SciELO and Cochrane databases using the terms: "Facebook Addiction," "Social Network Sites," "Facebook Abuse." The search covered the past 5 years up to January 2015. Articles that examine dependence on Facebook in the general population were included; we analyzed how this concept evolved over the last five years, and hope to contribute to the better understanding of the issue and its impacts.
RESULTS: Although controversial, published reports correlate Facebook addiction to mechanisms of reward and gratification. Some users developed an abusive relationship stimulated by the false feeling of satisfaction or as a way to feel better or more self-assured (increased level of excitement or escape). Studies from several countries indicate different prevalence, probably due to lack of consensus, and the use of different denominations, giving rise to the adoption of different diagnostic criteria.
CONCLUSION: Social Networks are modern communication tools; however, not only benefits, but also subsequent damage caused by its abusive use must be monitored. Many users with abusive usage and dependence recognize significant losses in their personal, professional, academic, social and family lives. Further investigation is needed to determine if abusive Facebook usage is a new psychiatric classification or merely the substrate of other disorders.

Keywords: Facebook Addiction, Facebook Abuse, Social Media Addiction, Social Media Abuse, Social Networking Sites Addiction.

Working memory dysfunction in insomniac adults: a systematic metanalytical review

Bárbara Monteiro; Maristela Candida; Suzana Monteiro; Flávia Paes; Ti-Fei Yuan; Ang Li; Xin Sun; Nuno Barbosa F. Rocha; Carlos Campos; Antonio Egidio Nardi; Sergio Machado


Abstract PDF

BACKGROUND: Insomnia is the most commonly occurring sleep disorder: recent reports estimate that 25-30% of adults in the general population occasional instances of experience insomnia, while 10% suffer from disturbances severe enough to meet diagnostic criteria for insomnia. Little is known about the mechanisms, causes, clinical course, and consequences of this condition. Over 30 studies have been published on the matter but only a small proportion has found differences in the working memory of individuals with vs. without insomnia.
OBJECTIVE: To summarize evidence regarding the differences in working memory performance between insomniac vs. normal adult sleepers.
METHODS: The survey was conducted using an advanced search in the ISI Web of Science and MEDLINE/PubMed with the terms "sleep", "insomnia" and "working memory" as major descriptors; these were crossed with the following keywords: "psychological tests", "neuropsychology" and "performance".
RESULTS: A total of 112 articles were identified in the search conducted in PubMed and Web of Science. After the screening, 102 articles unrelated to the proposed theme were excluded. Thus, 10 articles were analyzed by the eligibility and exclusion criteria, and included in this systematic review.
CONCLUSION: The information resulting from the analysis of the reviewed articles suggests that mild, but not definitive deficits in cognitive performance might be masked by insignificant disparities in studies comparing insomniac individuals with normal sleepers. This shortcoming can be circumvented by larger and better-characterized samples, together with optimized methodological control of factors which might otherwise result in confounding variations among participants.

Keywords: Insomnia, working memory, cognitive performance.

Aerobic exercise reduces anxiety symptoms and improves fitness in patients with panic disorder

Murilo Khede Lamego; Eduardo Lattari; Alberto Souza de Sá Filho; Flávia Paes; Jarbas Mascarenhas Jr.; Geraldo Maranhão Neto; Aldair José de Oliveira; Carlos Campos; Nuno Barbosa F. Rocha; Antonio E. Nardi; Sergio Machado


Abstract PDF

OBJECTIVE: To investigate the effects of a regularly repeated aerobic exercise series on anxiety and maximum oxygen consumption (VO2max) in Panic Disorder patients.
METHODS: Ten previously sedentary female subjects diagnosed with Panic Disorder performed 36 sessions of aerobic exercise (at 70 to 75% of VO2max), 3 times per week during 12 weeks. A cardiopulmonary evaluation (ergospirometry test) was used to set the intensity of training as well as to establish baseline and post-training VO2max parameters. The assessment of anxiety symptoms was performed at baseline, at the end of the 6th and 12th weeks, using the Trait Anxiety Inventory (STAI-T) and State Anxiety Inventory (STAI-S), and the Subjective Units of Distress Scale (SUDS) questionnaires. One-way ANOVA for repeated measurements (at 3 moments: Baseline, 6th week (mid-training) and 12th week (post-training) was used to compare the evolution of the questionnaires; the Bonferroni post hoc test was applied to identify differences between moments. A dependent t-test was performed for measures of VO2max.
RESULTS: Compared to baseline, (a) STAI-T showed significant anxiety reductions at mid- and post-training moments; (b) STAI-S and SUDS recorded anxiety reductions only at Post-training; (c) VO2max showed a significant improvement at Post-training.
CONCLUSION: This protocol promoted beneficial effects on cardiorespiratory fitness and anxiety levels of Panic Disorder patients.

Keywords: Panic disorder, aerobic exercise, maximum oxygen consumption.

Cognitive-behavioral therapy for schizophrenia: an overview on efficacy, recent trends and neurobiological findings

Maristela Candida; Carlos Campos; Bárbara Monteiro; Nuno Barbosa F. Rocha; Flávia Paes; António Egídio Nardi; Sérgio Machado


Abstract PDF

OBJECTIVE: Cognitive Behavioral Therapy (CBT) has been recommended by several international guidelines as the gold-standard treatment to address the needs of patients with schizophrenia. This review provides an overview on recent advances regarding CBT for schizophrenia.
METHODS: An electronic search was performed on PubMed/MEDLINE, Web of Science and Cochrane Database, using the key-words: "schizophrenia"; "psychosis"; "cognitive-behavioral therapy", "CBT"and "psychotherapy".
RESULTS: Numerous systematic reviews support the immediate and long-term efficacy of Cognitive Behavioral Therapy to reduce positive and negative symptoms in patients with schizophrenia. In the last decade, CBT for schizophrenia has been applied to clinical high-risk subjects and delivered using innovative approaches (low intensity, web-based and self-guided). Brain regions and networks which support high-level cognitive functions have been associated with CBT responsiveness. There is preliminary evidence indicating that CBT induces a prefrontal dependent increase in the top-down modulation of social threat activation.
CONCLUSION: In the last decade, CBT for schizophrenia has explored new treatment outcomes, targeted acute and pre-clinical populations and provided alternative methods to reach more patients and reduce intervention costs. The patients' neurocognitive profile seems to play a critical role in treatment response and combining CBT with cognitive remediation may allow to enhance therapeutic effects. Although CBT for schizophrenia is widely established as a gold-standard practice, future studies using innovative CBT protocols, exploring brain-related predictors and treatment outcomes may allow this intervention to be more effective, personalized and to reach a wider number of patients.

Keywords: Cognitive-behavioral therapy; Schizophrenia; Psychosis; Neurobiological; Neuroplasticity.

Involvement of beta absolute power in motor areas after hand immobilization: An EEG study

Dionis Machado; Jadna Helena dos Santos França; Silmar Teixeira; Victor Hugo do Vale Bastos; Maurício Cagy; Alberto Souza de Sá Filho; Sérgio Machado; Bruna Velasques; Pedro Ribeiro


Abstract PDF

OBJECTIVE: The purpose of this study was to analyze changes in beta band absolute power in cortical areas, before and after a condition of hand immobilization for 48 hours.
METHOD: Fifteen healthy volunteers, aged between 20 and 30, were submitted to EEG assessment before and after immobilization, while performing a motor task triggered by a visual stimulus.
RESULTS: Statistical analysis revealed that hand immobilization caused changes in cortical areas. Significant increases in beta band absolute power were found after hand immobilization at electrodes Fp2, C3 and P4. In contrast, at electrode C4 a decrease in beta band absolute power occurred after hand immobilization.
CONCLUSION: Predominant hand immobilization, even for 48 hours, is sufficient to cause cortical changes that affect movement planning. Such changes may represent a cortical strategy to supply cortical changes in contralateral hemisphere due to immobilization. Further studies are necessary to understand cortical changes due to hand immobilization and movement planning, especially considering how much time of immobilization is necessary to promote such changes.

Keywords: Beta band, Hand immobilization, Neural plasticity, Electroencephalography.

Gamma absolute power reveals activation of motor areas after hand immobilization

Dionis Machado; Jadna Helena dos Santos França; Silmar Teixeira; Victor Hugo do Vale Bastos; Rayele Pricila Moreira dos Santos; Maurício Cagy; Sergio Machado; Bruna Velasques; Pedro Ribeiro


Abstract PDF

OBJECTIVE: To analyze changes in gamma band absolute power in motor cortical areas, before and after a condition of hand immobilization for 48 hours.
METHOD: Fifteen healthy volunteers, aged between 20 and 30, were submitted to EEG assessment before and after 48 hours of immobilization of the dominant hand, while performing a motor task triggered by a visual stimulus. A two-way repeated measures ANOVA with two within-group factors (moment x condition), each one with two levels (before vs. after visual stimuli; before vs. after 48-hour HI, respectively) was used to test for changes in beta band absolute power.
RESULTS: Statistical analysis revealed that hand immobilization caused changes in cortical areas. A significant increase in gamma band absolute power was found after hand immobilization at electrodes F3 (p = 0.001) at F4 (p = 0.001) and at Fz (p = 0.001), at C3 (p = 0.001), C4 (p = 0.001) and Cz (p = 0.001).
CONCLUSION: These results reveal that oscillations of the gamma band can be a cortical strategy to solve the effect of less activation due to movement restriction. Knowledge of the functioning of motor cortical areas after a condition of immobilization can lead to more effective strategies in rehabilitation.

Keywords: Gamma band, EEG, Hand, Immobilization, Neural plasticity, Electroencephalography.

Association between depression severity and executive functioning in late-life depression: a systematic review

Suzana Monteiro; Bárbara Monteiro; Maristela Candida; Nathalia Adler; Carlos Campos; Nuno Barbosa F. Rocha; Flávia Paes; Antônio Egidio Nardi; Sergio Machado


Abstract PDF

OBJECTIVE: Late-life depression is an under-diagnosed and under-treated disease that reduces the well-being of older adults. Executive dysfunction is another critical impairment in elderly depressed individuals which further disrupts their everyday functioning. This systematic review aims to analyze the association between executive function and depression severity in elderly individuals diagnosed with major depressive disorder.
METHOD: The studies were retrieved from MEDLINE/PubMed, ISI Web of Knowledge and PsychInfo, after a search strategy combining the terms "depression", "executive function", "neuropsychological assessment", "elderly" and "late life". Study selection, data collection and quality ratings was performed by two independent raters.
RESULTS: A total of 1,130 articles were found but only 8 studies met the defined eligibility criteria and evaluated the association between depression severity and executive functioning. Six out of 8 studies found an association between depression severity and executive function, with correlations ranging from small to large (r= -0.15 to -0.53). The included reports had several methodological limitations such as selective data reporting, non-comprehensive executive function assessment and not controlling potential biases.
CONCLUSION: Depression severity may be more strongly correlated with a specific set of executive abilities although it also seems to be a broad-based association with executive functioning as a whole. Future high-quality prospective studies are recommended in order to understand the causal relationship between depression severity and executive functioning taking into account possible mediators such as age-related or neurodegenerative cognitive impairment, educational level and other clinic characteristics (e.g. age of onset, medication).

Keywords: Late-life Depression, Major Depressive Disorder, Executive Function.

Analysis of Reliability of Peak Treadmill Running in Maximum Progressive Effort Test: Influence of Training Level

Alberto Souza de Sá Filho; Wendel Alves; Thiago Gottgtroy Miranda; Eduardo Portuga; Sérgio Machado


Abstract PDF

OBJECTIVE: To determine the reliability (stability) of the peak velocity measurement (VPeak) derived from the incremental maximal effort test, as well as to establish the possible influence of the level of training on these responses.
METHOD: Thirty-eight male volunteers made two visits (3 - 5 days apart) to the training center where the study was conducted and performed maximal progressive running tests. The protocol consisted of increments of 0.5 km.h-1/min, starting at a running speed comfortable for each participant (7-9 km.h-1). All subjects were encouraged to achieve the maximum possible performance in both tests, with final voluntary exhaustion being the criterion for interruption.
RESULTS: The intra-class correlation coefficient presented excellent consistency of measurements (ICC = 0.975 - p = 0.001). The typical relative error of the measurement was 2.6% for the stability of the measurement of VPeak. Moreover, there were no significant differences between the individual coefficients of variation for measures 1 vs. 2 (p > 0.05). Graphical representation of Bland-Altman demonstrated a homogeneous distribution of the measurement error for all dependent variables.
CONCLUSION: Determination of VPeak exhibited excellent levels of reliability with small measurement errors. There was no influence of the training level on the reliability responses.

Keywords: Reliability; VO<sub>2Max</sub>; Aerobic Exercise; Aerobic Performance.

Acute effect of uphill running: current scenario and future hypotheses

Alberto Souza Sá Filho; Sérgio Machado


Abstract PDF

Strategies for metabolic adjustments are often considered by athletes throughout a running event. Planning for such events during training does not always include variations from level training, even though up/downhill exertion should definitely be a part of such planning. The differentiation of training stimuli, under adverse conditions of intensity and inclination, can generate differentiated benefits. However, uphill running raises expectations of deleterious effects. The imposition of different slope gradients throughout running could generate increased metabolic demands for sports performance. Thus, the present study aimed to answer questions mainly about the acute effects of uphill running, its relationship with aerobic performance, allowing us to introduce new hypotheses for future studies in the area on the subject. Gaps still need to be filled concerning the relevance of uphill running, and its determinants. Many of the points presently under scrutiny only lead to speculative explanations; for logical reasons, more studies should focus on the prescription of training at different slopes. This is the point at which specific conditioning is required, because the regulation of the effort and the energy cost resulting from the imposition of uphill running during competitive races depends heavily on previous experiences. This review will cover recently published research on the subject.

Keywords: Uphill Running; Kinematic Analysis; Stretching-Shortening Cycle; VO<sub>2Max</sub>.