Impaired Abdominal Skin Sensory Function in Morbid Obesity and After Bariatric Surgery

The perception of affective touch in women affected by obesity

Introduction

Pleasant and comforting bodily contacts characterized intimate and affective interactions. Affective touch informs us about others' emotions and intentions, sustains intimacy and closeness, protecting from loneliness and psychological distress. Previous evidence points to an altered experience of affective touch in clinical populations reporting interpersonal difficulties. However, there is no investigation of affective touch in obesity, which is often associated with negative affective-relational experiences since childhood.

Methods

This study aimed to provide the first evidence about the experience of affective touch in obesity by comparing 14 women with obesity with 14 women with healthy weight. Participants rated the pleasantness of both imagined and actual tactile stimuli, which consisted of (i) soft-brush strokes, (ii) touches of the experimenter's hand, and (iii) of a plastic stick (as control, non-affective, stimulation). Participants should report the pleasantness of each kind of touch. Moreover, we explored lifespan experiences of affective touch and interpersonal pleasure in social contexts through self-report questionnaires.

Results

No differences emerged for the pleasantness of affective touch (in both the real and imagery task) between the two groups. However, participants with obesity reported less frequent and less satisfying early experiences of affective touch when compared with the controls.

Discussion

Our results spoke in favor of a preserved experience of affective touch when experimentally probed in obesity, despite a limited early exposure to bodily affective contacts. We interpreted our results in the light of the social reconnection hypothesis. Nevertheless, we provided crucial methodological considerations for future research, considering that both the experimenter's and the brush touch may not resemble adequately real-life experiences, in which affective touch involves intimate people.

Body size estimation in obesity: a systematic review and meta-analysis

Previous research about body size estimation in obesity reported heterogeneous results. This might be related to the fact that the tasks adopted explored different body representations. Classifying the previous studies according to the specific body representation probed (i.e. implicit, explicit or both) might clarify discordant findings. A systematic review and meta-analysis of research articles assessing body size estimation in individuals affected by obesity compared with healthy weight individuals were performed in PubMed and Web of Science. Additional records were identified by reference lists inspection. The last search was run in May 2021. Two independent authors performed data extraction according to predefined criteria. Both groups either overestimated or underestimated the implicit body representation depending on the task used and the body part considered. Conversely, the explicit representation of the body was mainly overestimated by both individuals with obesity and healthy weight. In tasks relying on both these representations, overestimation and underestimation were reported in both groups, possibly depending on the degree of which each procedure relied on the explicit and/or implicit representation of the body. According to the meta-analysis, individuals with obesity tended to be significantly less accurate in body size estimations than participants with healthy weight. We confirmed that heterogeneous findings in body size estimation in obesity are related to the adoption of different tasks, which likely involve different body representations. We discussed the role of body dissatisfaction and altered somatosensation in the lower accuracy observed in obesity.