Smile (or grimace) through the pain? The effects of experimentally manipulated facial expressions on needle-injection responses

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Smiling has been previously shown to improve stress responses. We replicated and expanded this work by testing whether smiling helps with a potent real-world stressor: a vaccination-like needle injection. We also extended past research by examining grimacing, a facial expression known to naturally occur during stress and pain and one that shares some of the same facial action units as smiling. Participants (n = 231; [M]age = 19.2) were randomized to hold either a Duchenne smile, a non-Duchenne smile, a grimace, or a neutral expression while receiving a 25-gauge needle injection of saline solution. Expression was covertly manipulated via cover story and chopstick placement in the mouth. Heart rate (HR) and electrodermal activity (EDA) were collected continuously alongside self-reports of pain, emotion, and distress. Repeated-measures analysis of variance (ANOVA) indicated a between-subjects effect of facial condition on self-reported pain as well as a Condition × Time effect. Probing each time point revealed the strongest effect to be at needle injection, where the Duchenne smile and grimace groups reported approximately 40% less needle pain versus the neutral group. Repeated-measures ANOVAs also revealed differences between conditions for both HR and EDA. In post hoc analyses, only the Duchenne smile group exhibited significantly lower HR than neutral, with marginal Duchenne benefits found for EDA. Together, these findings indicate that both smiling and grimacing can improve subjective needle pain experiences, but Duchenne smiling may be better suited for blunting the stress-induced physiological responses of the body versus other facial expressions. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

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... The degree of difficulty of transitioning to a strong smile state when experiencing pain may depend on the reason for smiling. Amused smiles reflect a desire to convey a positive emotional state, to increase rapport with another person , whereas pain smiles may be expressed as a form of social appeasement (Singh & Manjaly, 2021) or facial feedback (which shows intraindividual differences) (Coles et al., 2019;Kraft & Pressman, 2012;Pressman et al., 2020). The current study corroborated evidence that differences in communicative gestures elicited by a given emotion can result in idiosyncratic state transitions. ...
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The life story, or narrative identity, is a psychosocial construction that brings together and integrates the self and experience within a broad story-based framework. Personality psychologists typically capture aspects of this inner story by prompting participants for descriptions of life chapters and/or specific and self-definitional autobiographical key scenes (e.g., high points, low points, turning points). Features of participants’ responses are then quantified for their thematic and/or structural content. There exists a number of additional and complementary assessment techniques that could buttress study of, and theory pertaining to, narrative identity. Here, I work to identify these assessments, which include self-reports, informant reports, and behavioral observations, and organize them within narrative identity’s nomological network. This work concludes with a number of suggestions for the ways in which traditional assessments may be better attuned to capture narrative identity’s integrative nature.
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