Touch-Avoidance and Touch-Seeking in Non-intimate Relationships: The Null Effects of Sightedness

People differ in their touch preferences and in the ways in which they touch others. People who are blind are particularly sensitive to tactile stimulation as a result of sensory compensation, and sense of touch can support their interpersonal communication. In the article presented here, we aimed to explore whether visual status predicts preferences for touch behaviors involving strangers; specifically, we examined touch-seeking and touch-avoidance in non-intimate interpersonal situations. Our study, whose participants comprised 43 individuals with congenital blindness, 53 individuals with adventitious blindness, and 47 sighted controls, showed that visual status does not predict touch-seeking or social touch-avoidance. We also observed similar gender differences in all participating groups, with women avoiding social touch more than men in non-intimate interpersonal situations involving strangers.

Responses to Stress: Investigating the Role of Gender, Social Relationships, and Touch Avoidance in Italy

Stress is a physiological response to internal and external events we call “stressors”. Response to the same daily stressors varies across individuals and seems to be higher for women. A possible explanation for this phenomenon is that women perceive sociality, relationships, and intimacy—important sources of both stress and wellbeing—differently from how men experience them. In this study, we investigate how gender, attachment, and touch avoidance predict stress responses on a sample of 335 Italians (216 females; age = 35.82 ± 14.32). Moreover, we analyze the network of relationships between these variables through multiple linear regression and exploratory network analysis techniques. The results recontextualize the role of gender in determining stress responses in terms of (lack of) confidence and touch avoidance toward family members; attitudes toward relationships seem to be the main determinants of stress responses. These results have implications for reducing stress in both clinical settings and at a social level.

The Na+-K+-ATPase is needed in glia of touch receptors for responses to touch in C. elegans

Increasing evidences support that accessory cells in mechanosensors regulate neuronal output; however, the glial molecular mechanisms that control this regulation are not fully understood. We show here in Caenorhabditis elegans that specific glial Na+-K+-ATPase genes are needed for nose touch-avoidance behavior. Our data support the requirement of these Na+-K+-ATPases for homeostasis of Na+ and K+ in nose touch receptors. Our data add to our understanding of glial regulation of mechanosensors.

Social touch observation in adults with autism: intact neural representations of affective meaning but lack of embodied resonance

Humans can easily grasp the affective meaning of touch when observing social interactions. Several neural systems support this ability, including theory of mind (ToM) and somatosensory resonance systems, but it is unclear how these systems are affected in autism spectrum disorder (ASD). Individuals with ASD are characterized by impairments in social interaction and the use of (non)verbal communication such as social and reciprocal touch. The present study applies an ecologically valid stimulus set and multivoxel pattern fMRI neuroimaging to pinpoint atypicalities in the neural circuitry underlying socio-affective touch observation in adults with ASD as compared to matched neurotypical controls. The MVPA results reveal that the affective meaning of touch is well represented in the temporoparietal junction, a core ToM mentalizing area, in both groups. Conversely, only the neurotypical group hosts affective touch representations in the somatosensory cortex, not the ASD group, yielding a significant group difference. Lastly, individuals with a more positive attitude towards receiving, witnessing, and providing social touch and with a higher score on social responsivity, show more differentiated representations of the affective meaning of touch in these somatosensory areas. Together, our findings imply that individuals with ASD are able to cognitively represent the affective meaning of touch, but they lack the spontaneous embodied somatosensory resonance when observing social touch communications. Individual differences in this diminished resonance appear to be related to social touch avoidance and quantitative autism traits.Significance StatementAutism is characterized by socio-communicative impairments, including abnormal processing of interpersonal touch. Little is known about the neural basis of atypicalities in social touch processing in autism. Here, adults with and without autism watched video clips displaying social touch interactions and judged the affective valence of the touch. Subsequently, they underwent functional magnetic resonance imaging while watching the same videos. Brain activity patterns demonstrate that adults with autism show intact cognitive understanding (i.e. “knowing”) of observed socio-affective touch experiences but lack of embodied emotional resonance (i.e. “feeling”). This lack of emotional resonance is linked to social touch avoidance and quantitative autism traits. These findings highlight that the depth of experiencing the state of others is shallower in people with autism.

Association of Touch Avoidance with Disease Severity and Quality of Life in Psoriasis Patients

Background and Objective Previous large studies have highlighted the impact of psoriasis on health-related quality of life (HRQoL) but not on interpersonal touch. This survey assessed the prevalence of touch avoidance among psoriasis patients, and its relationship to clinical characteristics and HRQoL. Methods Using an online, cross-sectional study with a standardized questionnaire, psoriasis patients reported their level of touch avoidance. The relationships between touch avoidance, patient-reported outcome measures, and patient demographics were analyzed using linear models for continuous outcomes and logistic models for categorical outcomes. Results Touch avoidance was reported by 48.2% of participants. Higher levels of touch avoidance were associated with worse HRQoL, depression, and itch outcomes (p<.001 for all). The strongest indicators of touch avoidance were HRQoL score (p<.001) and depression score (p<.001). Conclusion Nearly half of psoriasis patients report avoidance of touch. Those who had worse disease severity, HRQoL, and depression reported higher levels of touch avoidance.

An Exploration of the Interaction Between Touch Avoidance and the Pleasant Touch (C-Tactile Afferent) System

C-tactile (CT) afferent fibers are optimally stimulated by slow gentle stroking, and an inverted U-shaped relationship exists between stroking velocity and pleasantness ratings of this type of touch. This study investigated whether an additional and potentially important variable, touch avoidance, interacts with this relationship. While a typical U-shaped velocity–pleasantness relationship was expected, those high in touch avoidance were expected to rate CT-targeted touch (1–10 cm/s) as less pleasant than those low in touch avoidance. Thirty-five participants rated the pleasantness of a brush stroked across their forearm at five velocities (0.3, 1, 3, 10, 30 cm/s) administered by a custom-built touch stimulator (“the touch device”). Participants also completed two self-report measures of touch avoidance. There was an inverted U-shaped relationship between velocity and pleasantness ratings, and high touch avoidance resulted in a downward shift of this curve. The downward shift was across all velocities, including those that do not maximally engage CT afferents. It appears that touch avoidance reduces the pleasantness of all kinds of touch in a similar way, and it is unlikely to be specifically related to CT afferent functioning. Other potential mechanisms leading to touch avoidance are discussed.