The Experience of Affective Touch in Obesity

Study Overview
=================
Brief Summary
-----------------
The aim of the present research is to verify if the pleasantness of affective touch is comparable between women with obesity and healthy women, while measuring the level of social anhedonia and the lifespan experience of affective touch.

Official Title
-----------------
The Experience of Affective Touch in Obesity: the Role of Social Anhedonia and Lifespan Experiences

Conditions
-----------------
Obesity

Intervention / Treatment
-----------------
* Behavioral: Affective touch paradigm


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion criteria: right-handed; diagnosis of obesity (i.e., the level of body mass index (BMI( greater than or equal to 30). Exclusion Criteria: Concurrent neurological, neurodevelopmental (e.g., autism), motor, somatosensory and/or psychiatric disorders Evidence of any skin-related condition possibly affecting sensitivity on the participants' forearm (e.g., eczema, scars).

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 50 Years

Sexes Eligible for Study
-----------------
Female

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Cases<br>Right-handed women diagnosed with obesity will be consecutively recruited during their rehabilitative treatment at the Istituto Auxologico Italiano, IRCCS, San Giuseppe Hospital (Italy). Concurrent neurological, neurodevelopmental (e.g., autism), motor, somatosensory and/or psychiatric disorders will be exclusion criteria, as well as the evidence of any skin-related condition possibly affecting sensitivity on the participants' forearm (e.g., eczema, scars) | Behavioral: Affective touch paradigm<br>* Affective touch paradigm: experimental stimuli will include the touch of a soft cosmetic, a hand, which will be both expected to resemble affective pleasant stimulations, and a plastic stick with a rounded tip, as a control (non-affective) condition. Two speeds of stimulation will be adopted i) slow affective stimuli delivered at 3 cm/s and fast non-affective stimuli, delivered at non-optimal speed (18 cm/s). An imagery version of the task will be also administered: blindfolded participants will be asked to image the touches on their left forearm. After each (actual or imagined) tactile stimulus, individuals will rate the experience level of pleasantness. As part of the protocol, they will fill out two psychological questionnaires, assessing the level of social anhedonia and the amount and characteristics of the lifespan experiences of affective touch inclose relationships.<br>|
| Controls<br>Age-matched, right-handed, healthy women (i.e., with no history of eating disorders) will be recruited outside the hospital through personal contacts of the researchers and word-of-mouth. | Behavioral: Affective touch paradigm<br>* Affective touch paradigm: experimental stimuli will include the touch of a soft cosmetic, a hand, which will be both expected to resemble affective pleasant stimulations, and a plastic stick with a rounded tip, as a control (non-affective) condition. Two speeds of stimulation will be adopted i) slow affective stimuli delivered at 3 cm/s and fast non-affective stimuli, delivered at non-optimal speed (18 cm/s). An imagery version of the task will be also administered: blindfolded participants will be asked to image the touches on their left forearm. After each (actual or imagined) tactile stimulus, individuals will rate the experience level of pleasantness. As part of the protocol, they will fill out two psychological questionnaires, assessing the level of social anhedonia and the amount and characteristics of the lifespan experiences of affective touch inclose relationships.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rating of subjective pleasantness | Behavioural outcome associated with the experimental paradigm: participants will be asked to rate the pleasantness of the tactile stimuli after each stimulation with a score ranging from zero not pleasant at all) to 100 (extremely pleasant). | baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Social anhedonia score | Social anhedonia will be evaluated with the Anticipatory and Consummatory Interpersonal Pleasure Scale (ACIPS, Gooding and Pflum, 2014); this is a 17-item self-report measure of individuals' tendency to look forward to interactions with others (anticipatory interpersonal pleasure - 7 items) and experienced pleasure in social interactions (consummatory interpersonal pleasure - 10 items). The ACIPS is scored on a Likert scale ranging from 1 (very false for me) to 6 (very true for me); higher scores indicate higher anticipatory and consummatory interpersonal pleasure. | baseline | 
| Affective experience score | The lifespan experience of affective touch in close relationships will be assessed with the Tactile Biography questionnaire (TBIO, Beltrán et al., 2020). This includes a 29-item self-report measure scored on a Likert scale ranging from 1 (e.g., not at all true for me) to 5 (e.g., extremely true) that evaluate four independent components: the frequency of and satisfaction for affective touch i) in childhood/adolescence and ii) adulthood, iii) comfort with and iv) fondness for interpersonal touch in close relationships | baseline | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
affective touch, social anhedonia, lifespan bodily contacts, interpersonal relationships