Made available in DSpace on 2014-12-17T14:44:18Z (GMT). No. of bitstreams: 1 LuizFFJ_DISSERT.pdf: 561001 bytes, checksum: d3e0298e76c38d08d3b0c195db8c91b5 (MD5) Previous issue date: 2014-04-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The complex human behavior related to exercise involves cognitive, physical and emotional processing. The recent theories about exercise s intensity regulation have highlighted the role played by psychophysics aspects in controlling exercise s intensity. In this regard, recent evidences have shown that there is variability in human capacity in perceiving interoceptives clues. Thus, subjects more sensitive show higher physiological arousal to physical and/or emotional stress, and sensations with higher intensity. In fact, studies have evidenced that interoceptive feedback modifies behavior in exercise with free load. However, exercise recommendations are based in a constant load standard. Therefore, we aimed to analyze the influence of interoceptive sensibility on psychophysics responses during dynamic exercise performed with constant load. Twenty-four adult males were allocated into two groups accordingly with their interoceptive sensibility: high sensibility (n=11) and low sensibility (13). They underwent to an incremental test (IT) and then randomly to two sections of moderate and severe exercise intensity for 20 minutes. Heart rate (HR), rating of perceived exertion (RPE), affective feelings (AF), alert state (AS), and percentage of associative thoughts were collect during exercise. A two-way ANOVA with repeated measures was used to assess differences between psychophysics responses. There were differences between group in RPE, AF, and AS in moderate intensity. There was no difference in any measure in severe intensity. We conclude that subjects with high interoceptive sensibility feel dynamic moderate exercise more intense than the subjecs with low interoceptive sensibility / INTRODU??O: O complexo comportamento humano de realizar exerc?cio f?sico envolve processamento cognitivo, f?sico e emocional. As recentes teorias sobre fadiga e reposta afetivas ao exerc?cio f?sico atribuem importante papel na regula??o da intensidade do esfor?o aos fatores interoceptivos. Al?m disso, Evid?ncias recentes tem apontado haver variabilidade na capacidade humana em perceber esses est?mulos interoceptivos. Dessa forma, pessoas mais sens?veis apresentam excita??o fisiol?gica mais acentuada ao estresse f?sico e/ou emocional, e maior intensifica??o dessas sensa??es. Adicionalmente, estudos tem relatado que feedback interoceptivo diminui a intensidade do esfor?o exercida, e que pessoas com maior sensibilidade interoceptiva controlam melhor a intensidade de esfor?o em tarefas com ritmo livre. Contudo, os modelos de prescri??o de exerc?cio f?sico din?mico apresentam padr?o de intensidade de esfor?o fechado, e n?o ? conhecida as repostas psicofisiol?gicas entre os grupos de variabilidade interoceptiva durante a realiza??o de exerc?cio f?sico. OBJETIVO: O presente estudo verificou a influ?ncia da sensibilidade interoceptiva sobre as repostas psicofisiol?gicas em exerc?cio din?mico com carga constante. M?TODOS: A amostra foi composta por 24 homens jovens adultos, insufientemente ativos, que foram designados a dois grupos de acordo com seus n?veis de sensibilidade interoceptiva: Alta sensibilidade (n=11) e Baixa sensibilidade (n=13). Todos foram submetidos a um teste incremental (TI) em cicloerg?metro para identifica??o do limiar de variabilidade da frequ?ncia card?aca (LiVFC) e da pot?ncia pico (PP). Posteriormente, os sujeitos foram submetidos (em ordem aleat?ria e cruzada) a dois protocolos experimentais de exerc?cio f?sico em cicloerg?metro durante 20 minutos com intensidade correspondente a 20% abaixo e 20% acima LiVFC. Durante os protocolos experimentais as respostas de Frequ?ncia Card?aca (FC), Percep??o Subjetiva de Esfor?o (PSE), Val?ncia Afetiva (VA), Estado de Alerta e N?vel de pensamento Dissociativo-Associativo ao exerc?cio f?sico foram registradas. O teste de Shapiro-Wilk e as an?lises da m?dia, assimetria e curtose verificaram a normalidade de distribui??o dos dados. O Teste de Mauchly verificou a esfericidade dos dados de medidas repetidas. O Teste t para amostra independente e o Teste de Mann Whitney verificaram as igualdade dos dados descritivos entre os grupos. A ANOVA two away (grupo x momentos) para medidas repetidas verificou as poss?veis diferen?as entre as respostas psicofisiol?gicas. RESULTADOS: Houve diferen?a estatisticamente significante entre os grupos na PSE (F(3,36)=18,50, p=0,000), VA (F(3,36)=4,14, p=0,01) e no Estado de Alerta (F(3,36)=4,03, p=0,01) no exerc?cio realizado em intensidade correspondente a 80% LiVFC. Na intensidade correspondente a 120% LiVFC n?o houve diferen?a entre os grupos, somente entre os momentos em cada grupo. CONCLUS?O: A sensibilidade interoceptiva modifica as respostas psicofisiol?gicas durante a realiza??o de exerc?cio f?sico din?mica com intensidade moderada (abaixo do LiVFC)

In the last decade, neuroscience and psychology alike have paid increasing attention to the study of affective touch, which refers to the emotional and motivational facets of tactile sensation. Some aspects of affective touch have been linked to a neurophysiologically specialised system, namely the C tactile (CT) system. While the role of this system for affiliation, social bonding and communication of emotions have been investigated, less is known about the potential role of affective touch in the awareness of the body as our own, i.e. as belonging to our psychological 'self'. This thesis attempted to contribute to the knowledge on affective touch and its relation to body awareness, by exploring the potential role of this modality to the way we perceive and make sense of our body as our own. Specifically, this work aimed to advance the current state of knowledge by investigating: 1) the effect of affective touch on the sense of body ownership, which is a fundamental aspect of body awareness; 2) the relation between interoceptive modalities, originating both internally (i.e. cardiac awareness) and peripherally (i.e. affective touch), and exteroception in body awareness; 3) the effect of intranasal oxytocin on the perception of affective touch and bodily awareness; 4) the perception and social modulation of affective touch in psychiatric patients who show difficulties in body awareness, namely patients with Anorexia Nervosa, and 5) the modulating role of self-other distinction and of self-other relation in the perception of affective touch and body awareness. In a first experiment (N = 52) the rubber hand illusion paradigm was used to investigate the role played by CT-optimal, affective touch in the sense of body ownership. The results showed that slow, pleasant touch enhanced the experience of embodiment in comparison to faster, neutral touch, suggesting that affective touch might uniquely contribute to the sense of body ownership. The following study (N = 75), used a similar methodology to test whether interoceptive sensitivity as measured by a heartbeat counting task would modulate the extent to which affective touch influences the multisensory process taking place during the rubber hand illusion. The results could not confirm a systematic relation between interoceptive sensitivity and the perception of affective touch, nor its influence on body ownership. The next study (N = 41) included a double-blind, placebo-controlled, randomised, cross-over design testing the effect of intranasal oxytocin on the perception of affective touch and body ownership, as measured by means of the rubber hand illusion. There was no evidence supporting the hypothesis that intranasal oxytocin could influence the CT system as tested in this study. The next study (N = 55) applied some of the above methodologies to investigate the perception of CT-optimal touch in patients with anorexia nervosa and its emotional modulation by top-down factors. The results confirmed the hypothesis that people with anorexia nervosa show a reduced perception of affective touch compared to healthy controls, but its perception was not influenced by top-down affective modulation, in the sense that both patients and healthy controls perceived touch as more pleasant when presented concurrently with positive facial expressions compared to neutral and negative faces. Finally, the last two studies (N = 76 and 35 healthy volunteers, respectively) focused on the relationship between affective touch and body awareness in the context of social cognition. These studies used both online and offline social modulation paradigms to investigate the role of self-other distinction and of self-other relation in the perception of affective touch. The results showed that positive top-down social information can enhance the perceived pleasure of tactile stimulation. Taken together, these studies point to the central role of affective touch in body awareness and social cognition. Finally, they also pave the way for future studies examining the role of disruptions of the CT system in the development of neuropsychiatric impairments of body awareness and social cognition.