Laura Alice Santos de Oliveira

Autonomic reactions to mutilation pictures: Positive affect facilitates safety signal processing

For survival, humans are continuously vigilant for signs of danger. Equally important, but less studied, is our ability to detect and respond to safety cues. The trait of positive affect may be a key component determining human variability in safety detection. Here we investigate autonomic and self-report reactivity to pictures of mutilated bodies, after reading a text about the art of mimicking injuries in the movies. Participants that scored high in positive affect trait showed attenuated autonomic reactions to the mutilation pictures. Thus, high positive affect facilitated engagement in safety cues and modulated reflexive reactions of the brains defense system.

Preparing to Grasp Emotionally Laden Stimuli

Background Contemporary theories of motor control propose that motor planning involves the prediction of the consequences of actions. These predictions include the associated costs as well as the rewarding nature of movements’ outcomes. Within the estimation of these costs and rewards would lie the valence, that is, the pleasantness or unpleasantness of a given stimulus with which one is about to interact. The aim of this study was to test if motor preparation encompasses valence. Methodology/Principal Findings The readiness potential, an electrophysiological marker of motor preparation, was recorded before the grasping of pleasant, neutral and unpleasant stimuli. Items used were balanced in weight and placed inside transparent cylinders to prompt a similar grip among trials. Compared with neutral stimuli, the grasping of pleasant stimuli was preceded by a readiness potential of lower amplitude, whereas that of unpleasant stimuli was associated with a readiness potential of higher amplitude. Conclusions/Significance We show for the first time that the sensorimotor cortex activity preceding the grasping of a stimulus is affected by its valence. Smaller readiness potential amplitudes found for pleasant stimuli could imply in the recruitment of pre-set motor repertoires, whereas higher amplitudes found for unpleasant stimuli would emerge from a discrepancy between the required action and their aversiveness. Our results indicate that the prediction of action outcomes encompasses an estimate of the valence of a stimulus with which one is about to interact.

Corticospinal Excitability Preceding the Grasping of Emotion-Laden Stimuli

Evolutionary theories posit that emotions prime organisms for action. This study examined whether corticospinal excitability (CSE) is modulated by the emotional valence of a to-be-grasped stimulus. CSE was estimated based on the amplitude of motor evoked potentials (MEPs) elicited using transcranial magnetic stimulation (TMS) and recorded on the first dorsal interosseous (FDI) muscle. Participants were instructed to grasp (ACTION condition) or just look at (NO-ACTION condition) unpleasant, pleasant and neutral stimuli. TMS pulses were applied randomly at 500 or 250 ms before a go signal. MEP amplitudes were normalized within condition by computing a ratio for the emotion-laden stimuli by reference to the neutral stimuli. A divergent valence effect was observed in the ACTION condition, where the CSE ratio was higher during the preparation to grasp unpleasant compared to pleasant stimuli. In addition, the CSE ratio was lower for pleasant stimuli during the ACTION condition compared to the NO-ACTION condition. Altogether, these results indicate that motor preparation is selectively modulated by the valence of the stimulus to be grasped. The lower CSE for pleasant stimuli may result from the need to refrain from executing an imminent action.

Adaptação transcultural para o português do instrumento Peritraumatic Dissociative Experiences Questionnaire, Versão Auto-Aplicativa

INTRODUCCION: El articulo presenta la adaptacion transcultural al portugues del instrumento Peritraumatic Dissociative Experiences Questionnaire, Self-Report Version (PDEQ-SRV), para rastrear y cuantificar los fenomenos disociativos peritraumaticos. METODOS: Se hicieron dos traducciones y sus respectivas re-traducciones, evaluacion de la equivalencia semantica, elaboracion de la version sintesis, pre-test en el publico-objetivo y realizacion de la version final. RESULTADOS: Se observo un alto grado de equivalencia semantica entre el instrumento original y los dos pares de traducciones/re-traducciones, desde la perspectiva de los significados referencial y general. El pre-test en el publico-objetivo condujo a pocas modificaciones que confirmaron la realizacion de los criterios de equivalencia semantica. DISCUSION: El trabajo permite la primera adaptacion para el contexto brasileno de un instrumento especifico para identificacion y cuantificacion de sintomas disociativos peritraumaticos.BACKGROUND: This paper presents the cross-cultural adaptation to Brazilian Portuguese of the Peritraumatic Dissociative Experiences Questionnaire, Self-Report Version (PDEQ-SRV), aimed at the screening and quantification of peritraumatic dissociative phenomena. METHODS: Two translations and their respective back-translations were carried out, followed by semantic equivalence evaluation, preparation of the synthesis version, pre-testing in the target population, and definition of the final version. RESULTS: A high level of semantic equivalence was observed between the original instrument and the two pairs of translations/back-translations in terms of the referential and general meanings. The pre-testing stage in the target population led to few alterations aiming at fulfilling semantic equivalence criteria. DISCUSSION: This study presents the first adaptation to the Brazilian context of an instrument specifically designed to detect and quantify peritraumatic dissociative symptoms.

Observing Grasping Actions Directed to Emotion-Laden Objects: Effects upon Corticospinal Excitability

The motor system is recruited whenever one executes an action as well as when one observes the same action being executed by others. Although it is well established that emotion modulates the motor system, the effect of observing other individuals acting in an emotional context is particularly elusive. The main aim of this study was to investigate the effect induced by the observation of grasping directed to emotion-laden objects upon corticospinal excitability (CSE). Participants classified video-clips depicting the right-hand of an actor grasping emotion-laden objects. Twenty video-clips differing in terms of valence but balanced in arousal level were selected. Motor evoked potentials (MEPs) were then recorded from the first dorsal interosseous using transcranial magnetic stimulation (TMS) while the participants observed the selected emotional video-clips. During the video-clip presentation, TMS pulses were randomly applied at one of two different time points of grasping: (1) maximum grip aperture, and (2) object contact time. CSE was higher during the observation of grasping directed to unpleasant objects compared to pleasant ones. These results indicate that when someone observes an action of grasping directed to emotion-laden objects, the effect of the object valence promotes a specific modulation over the motor system.

Abordagem fisioterapêutica da ataxia espinocerebelar: uma revisão sistemática

La ataxia espinocerebelosa (SCA) es una afeccion hereditaria que cursa con la degeneracion progresiva del cerebelo y de sus vias, lo que causa alteraciones del equilibrio y de otras funciones. El resultado de los abordajes de la fisioterapia en el tratamiento de la SCA y la cualidad metodologica de estos estudios fueron analizados. Se investigo si los beneficios alcanzados con el tratamiento fueron retenidos. Las intervenciones encontradas incluyen entrenamiento del equilibrio, marcha y coordinacion; fortalecimiento; canilleras en los miembros durante ejercicios y aplicacion de la estimulacion magnetica transcraneana. La retencion de las mejorias obtenidas con el tratamiento fue relacionada al grado de evolucion de la SCA y a la continuidad de la practica de ejercicios. Aunque nuevos estudios con mayor caracter cientifico son necesarios para elegir los abordajes mas adecuados para el tratamiento de los portadores de la SCA.AbstrAct | The spinocerebellar ataxia (SCA) is an in-herited disorder that leads to progressive degeneration of the cerebellum and its pathways with impairments of balance and other functions. Physical therapy studies for SCA treatment and their methodological quality were examined. We also investigated if the benefits achieved with treatment can be retained. The interventions iden-tified included balance, gait and coordination training; strengthening; weights around the limbs during exercise and transcranial magnetic stimulation. The long-term im-provements were related to the degree of SCA evolution and the continuity of exercise practice. Nevertheless, further studies with higher scientific accuracy are neces -sary to elect the best physical therapy approaches for SCA patients.Keywords | spinocerebellar ataxia; physiotherapy; hereditary ataxia.rEsUMO | A ataxia espinocerebelar (SCA) e uma afeccao hereditaria que cursa com a degeneracao progressiva do cerebelo e suas vias, causando alteracoes do equilibrio e de outras funcoes. O efeito das abordagens da fisioterapia no tratamento da SCA e a qualidade metodologica des-ses estudos foram analisados. Foi investigado ainda se os beneficios alcancados com o tratamento sao retidos. As intervencoes encontradas incluem treino do equilibrio, marcha e coordenacao; fortalecimento; caneleiras nos membros durante exercicios e aplicacao de estimulacao

Reference Values for Human Posture Measurements Based on Computerized Photogrammetry: A Systematic Review

Objective: The main objective of this study was to review the literature to identify reference values for angles and distances of body segments related to upright posture in healthy adult women with the Postural Assessment Software (PAS/SAPO). Methods: Electronic databases (BVS, PubMed, SciELO and Scopus) were assessed using the following descriptors: evaluation, posture, photogrammetry, physical therapy, postural alignment, postural assessment, and physiotherapy. Studies that performed postural evaluation in healthy adult women with PAS/SAPO and were published in English, Portuguese and Spanish, between the years 2005 and 2014 were included. Results: Four studies met the inclusion criteria. Data from the included studies were grouped to establish the statistical descriptors (mean, variance, and standard deviation) of the body angles and distances. A total of 29 variables were assessed (10 in the anterior views, 16 in the lateral right and left views, and 3 in the posterior views), and its respective mean and standard deviation were calculated. Reference values for the anterior and posterior views showed no symmetry between the right and left sides of the body in the frontal plane. There were also small differences in the calculated reference values for the lateral view. Conclusion: The proposed reference values for quantitative evaluation of the upright posture in healthy adult women estimated in the present study using PAS/SAPO could guide future studies and help clinical practice.

Balance Impairments after Brachial Plexus Injury as Assessed through Clinical and Posturographic Evaluation

Objective: To investigate whether a sensorimotor deficit of the upper limb following a brachial plexus injury (BPI) affects the upright balance. Design: Eleven patients with a unilateral BPI and 11 healthy subjects were recruited. The balance assessment included the Berg Balance Scale (BBS), the number of feet touches on the ground while performing a 60 s single-leg stance and posturographic assessment (eyes open and feet placed hip-width apart during a single 60 s trial). The body weight distribution (BWD) between the legs was estimated from the center of pressure (COP) lateral position. The COP variability was quantified in the anterior-posterior and lateral directions. Results: BPI patients presented lower BBS scores (p = 0.048) and a higher frequency of feet touches during the single-leg stance (p = 0.042) compared with those of the healthy subjects. An asymmetric BWD toward the side opposite the affected arm was shown by 73% of BPI patients. Finally, higher COP variability was observed in BPI patients compared with healthy subjects for anterior-posterior (p = 0.020), but not for lateral direction (p = 0.818). Conclusions: This study demonstrates that upper limb sensorimotor deficits following BPI affect body balance, serving as a warning for the clinical community about the need to prevent and treat the secondary outcomes of this condition.

Decreasing fall risk in spinocerebellar ataxia.

[Purpose] Spinocerebellar ataxia consists of a group of autosomal dominant disorders that cause progressive degeneration, mainly in the cerebellum and its connections. Falls, which are a significant concern of this condition, reduce patients’ mobility, deteriorate their health and have physical and social consequences. The aim of this study was to test the effectiveness of a modified protocol for improving balance and diminishing the fall risk of spinocerebellar ataxia patients exclusively. [Subjects and Methods] Exercises aiming to improve static and dynamic balance, whole body movements, measures to prevent falls and falling strategies were performed twice per week for four weeks by 11 spinocerebellar ataxia patients. Balance was evaluated using the Berg Balance Scale. [Results] The results show that there was a significant increase in Berg Balance Scale scores after the interventions (Wilcoxon p=0.0034). [Conclusion] This study demonstrated that the modified protocol is effective at reducing the fall risk of spinocerebellar ataxia patients. This protocol may be a useful option for appropriately coping with falls caused by spinocerebellar ataxia.

Partial Body Weight-Supported Treadmill Training in Spinocerebellar Ataxia

Background and Purpose The motor impairments related to gait and balance have a huge impact on the life of individuals with spinocerebellar ataxia (SCA). Here, the aim was to assess the possibility of retraining gait, improving cardiopulmonary capacity, and challenging balance during gait in SCA using a partial body weight support (BWS) and a treadmill. Also, the effects of this training over functionality and quality of life were investigated. Methods Eight SCA patients were engaged in the first stage of the study that focused on gait training and cardiovascular conditioning. From those, five took part in a second stage of the study centered on dynamic balance training during gait. The first and second stages lasted 8 and 10 weeks, respectively, both comprising sessions of 50 min (2 times per week). Results The results showed that gait training using partial BWS significantly increased gait performance, treadmill inclination, duration of exercise, and cardiopulmonary capacity in individuals with SCA. After the second stage, balance improvements were also found. Conclusion Combining gait training and challenging tasks to the postural control system in SCA individuals is viable, well tolerated by patients with SCA, and resulted in changes in capacity for walking and balance.