Vicarious ratings of self vs. other-directed social touch in women with and recovered from Anorexia Nervosa

Abstract

Anorexia Nervosa (AN) is an eating pathology characterized by restricted eating, body image distortions and impaired socio-cognitive abilities. Altered responses to affective touch—a pleasant interoceptive stimulus hypothesised to involve activation of the C-Tactile (CT) system, may contribute to the aetiology and maintenance of this disorder. Here, we investigated whether third-party social touch vicarious ratings of different body sites at CT-optimal vs. non-CT optimal velocities differed in women with and recovered from AN (RAN) and healthy controls (HCs). Thirty-five HCs, 27 AN and 29 RAN provided pleasantness ratings for two different tasks designed to probe expectations of how touch is perceived by self (self-directed touch) vs. others (other-directed touch). Findings revealed that both clinical groups, compared to HCs, did not differ in their pleasantness ratings to touch for another but when evaluating touch for self, both clinical groups rated CT-optimal touch as less pleasant than HCs. These findings suggest that AN and RAN women demonstrate an atypical vicarious pleasantness response to affective touch involving self, but not others. Novel therapeutic approaches that help anorexics to better interpret or improve tolerance of affective tactile experiences involving the self may be an important addition to current standard treatments.

From Virtual Reality to Regenerative Virtual Therapy: Some Insights from a Systematic Review Exploring Inner Body Perception in Anorexia and Bulimia Nervosa

“…Table 1 shows study characteristics according to extraction parameters. Sixteen studies explored interoception in AN or BN [ 71 , 74 , 75 , 76 , 77 , 78 , 80 , 81 , 82 , 83 , 86 , 87 , 89 , 90 , 91 , 92 ], five investigated proprioception [ 71 , 79 , 84 , 88 , 93 ] and one vestibular signals [ 85 ]. Among these studies, one [ 71 ] assessed interoception and proprioception within the same work.…”

“…One study [ 83 ] was a single case study on a patient with AN who was compared with a group of four HCs. Two studies [ 75 , 85 ] compared patients with AN, BN, and a group of HCs, one study [ 92 ] compared patients with BN with HCs and other two studies compared the clinical sample (i.e., AN) both with HCs and with recovered patients [ 77 , 81 ]. Lastly, one study compared patients with AN, HCs, and patients reporting functional motor symptoms [ 82 ].…”

“…Three studies [ 77 , 80 , 81 ] assessed interoception using Affective Touch [ 98 , 99 , 100 , 101 ]. In Bellard et al [ 77 ] the Affective Touch consisted of Self and Other-directed Affective Touch video clips.…”

“…Three studies [ 77 , 80 , 81 ] assessed interoception using Affective Touch [ 98 , 99 , 100 , 101 ]. In Bellard et al [ 77 ] the Affective Touch consisted of Self and Other-directed Affective Touch video clips. Specifically, touch was delivered across five different body regions: non-C Tactile (CT)-innervated body site (i.e., palm) vs. CT-innervated body sites (i.e., ventral forearm, upper arm, cheek, and back) with three different speeds: static (0 cm/s), slow (5 cm/s) and fast (30 cm/s).…”

“…To avoid visual feedback, in this study participants were blindfolded throughout the task. As with Bellard et al [ 77 ], the study by Crucianelli et al [ 81 ] compared persons with AN, recovered patients, and HCs.…”