Background: Clinical findings indicate that touch massage has the ability to induce positive emotions and influence stress responses. However, little is known about mechanisms that can explain observed responses. Aim: To understand mechanisms behind observed emotional and physiological responses during and after touch massage. Methods: This thesis is based upon healthy volunteers in Studies I, II, IV and patients undergone aortic surgery in Study III. Study I had a crossover design, participants served as their own controls. After randomization they received TM on one occasion and the other occasion served as control. Heart rate variability (HRV), heart rate (HR) saliva cortisol concentration, glucose, insulin in serum and extracellular (ECV) levels of glucose, lactate, glycerol and pyruvat were measured before, during and after TM/control. In study II, functional magnetic resonance imaging (fMRI) was used in order to measure brain activity during TM movement. The study design included four different touch stimulations, human touch with movement (TM movement) human stationary touch and rubber glove with or without movement. Force (2.5 N) and velocity (1.5 cm/s) were held constant across conditions. The pleasantness of the four different touch stimulations was rated on a visual analog scale (VAS-scale). Study III had a randomized controlled design. The intervention group received TM and the control group rested. HRV, cortisol, glucose, insulin in serum, blood pressure, oxygen saturation, respiratory frequency and anxiety levels were measured before, during and after TM/control. In study IV participants were interviewed about experiences after TM and the text was analyzed in by qualitative content analyze. Results: Study I. TM reduced the stress response as indicated by decreased heart rate and decreased activity in the sympathetic nervous system, followed by a compensatory decrease in parasympathetic nervous activity in order to maintain balance. Cortisol and insulin levels decreased significantly after intervention, while serum glucose levels remained stable. A similar, though less prominent, pattern was seen during the control session. There were no significant differences in ECV concentrations of analyzed substances. Study II. Human moving touch (TM movement) was significantly rated as the most pleasant touch stimulation. The fMRI results revealed that human moving touch (TM movement) most strongly activated the pregenual anterior cingulate cortex (pgACC). Study III. Selfrated anxiety levels significantly decreased in the patient group that received TM compared with control group. There were no significant differences in physiological stress-related outcome parameters between patients who received touch massage and controls. Study IV. In this study participants talked about the experience of TM in terms of rewards. Expressions like need, desire, pleasure and conditioning could be linked with a theoretical model of reward. Four different categories were identified as wanting, liking, learning and responding. In conclusion: Results from these studies indicate that receiving TM is experienced as rewarding. Touch massage movement activates a brain area involved in coding of rewarding pleasant stimulations. TM decreases anxiety and dampens the stress response by a decreased activation of the sympathetic nervous activity. Our results indicate that TM is a caring intervention that can be used to induce pleasure, decrease anxiety and stress in the receiver.

Introduction : Le système nerveux autonome (SNA) est le marqueur le plus puissant du vieillissement global de l'organisme, en particulier du vieillissement vasculaire cérébral et cardiaque. Bien que la peau soit richement innervée par les nerfs autonomes et le SNA contrôle de nombreuses fonctions cutanées, la relation entre le SNA et le vieillissement cutané n'a pas été étudiée. Méthodes : Nous avons évalué le vieillissement cutané chez 209 sujets âgés (105 femmes et 104 hommes, âge moyen 77,5 ans) appartenant à la cohorte stéphanoise PROOF (PROgnostic indicator OF cardiovascular and cerebrovascular events) qui explore la fonctionnalité du SNA. Le vieillissement cutané a été mesuré par le score clinique SCINEXA (SCore for INtrinsic and EXtrinsic skin Aging), par VISIA, vidéodermatoscopie et cutométrie. L’activité du SNA a été mesurée par la variabilité de la fréquence cardiaque sur enregistrement de l’électrocardiogramme de 24 heures. Résultats : Une relation entre SNA et SCINEXA n’a pas pu être démontrée. Cependant, une relation entre l'activité du SNA et certains items du SCINEXA et certains paramètres du VISIA, de la vidéodermatoscopie et de la cutométrie a été trouvée. En particulier, l'analyse des paramètres VISIA a mis en évidence une relation entre porphyrines élevées et baisse de l’activité sympathique du SNA. Discussion et Conclusion : Quoique nous n’ayons pas trouvé de relation entre le vieillissement cutané global et la fonction du SNA, il est possible que le SNA joue un rôle sur le vieillissement intrinsèque de la peau, mais d’une manière négligeable en comparaison des facteurs externes tels que l’exposition solaire, et que cette partie du vieillissement soit difficile à mettre en évidence. De plus ayant trouvé une relation entre certains paramètres du vieillissement cutané et le SNA, notre étude encourage les futures recherches sur l’influence du SNA sur les différents composants du vieillissement cutané / Background : The autonomic nervous system (ANS) is the most powerful marker of the overall body aging, especially for what concerns the vascular aging of the heart and the brain. Although the skin is richly innervated by ANS nerves and the ANS controls many skin functions, the relation between the ANS and skin aging has not been studied. Methods : We evalusated skin aging of 209 elderly subjects (105 women and 104 men, mean age 77.5 years) belonging to the PROOF (PROgnostic indicator OF cardiovascular and cerebrovascular events) cohort of Saint-Etienne which explores the functionality of the ANS. Skin aging was measured by the clinical score SCINEXA (SCore for INtrinsic and EXtrinsic skin Aging), by VISIA, videodermoscopy and cutometry. The ANS status was measuredby the heart rate variability on a 24 hours recording of the electrocardiogram. Results : A relation between ANS and SCINEXA could not be demonstrated. However, a relation between the activity of the ANS and some items of SCINEXA and certain parameters of VISIA, videodermoscopy and cutometry was found. In particular, the analysis of VISIA parameters showed a relation between elevated porphyrins and a decreased sympathetic activity of the ANS. Discussion and conclusion : Although we did not find a relationship between overall skin aging and ANS activity, ANS might play a role in intrinsic skin aging, albeit marginally if compared to external factors such a sun exposure. Moreover, the intrinsic part of the skin aging and the ANS, our study encourages further research on the influence of the ANS on the various components of skin aging.