Affectionate Touch to Promote Relational,Psychological,and Physical Well-Being in Adulthood: A Theoretical Model and Review of the Research

Affectionate Touch

Interpersonal touch is a diverse behavior; people touch one another in many ways, for many reasons, and in many contexts (Jones & Yarbrough, 1985; Pisano, Wall, & Foster, 1986). A touch is considered affectionate if it is intended by the touch provider to demonstrate love, care, fondness, or appreciation (Floyd, 2006), or if that type of touch is typically assumed to indicate affection, such as hugging, kissing, caressing, holding hands, stroking another person’s face, hair, arms, back or legs, and other non-sexual physical contact (e.g., K. L. Johnson & Edwards, 1991; Jones & Yarbrough, 1985; Pisano et al., 1986). People generally like to give and receive affectionate touch in their close relationships and do so regularly (e.g., Anderson & McCormack, 2014; van Anders, Edelstein, Wade, & Samples-Steele, 2014). Sexual physical contact also may be included in a definition of affectionate touch, but it is a specific subcategory of touch that differs from other types of physical affection (Birnie-Porter & Lydon, 2013). Sex is a biological drive with a specific reproductive function, and it may or may not be affectionate depending on the meaning and behaviors involved in the sexual encounter. Thus, this theoretical perspective will emphasize non-sexual affectionate touch in adult close relationships.

In addition, the theoretical model we propose focuses on receiving affectionate touch from a close other (e.g., romantic partner, best friend, sibling). Touch is, by definition, a dyadic behavior, and touch interactions often include both receiving and providing touch in a reciprocal and synergistic exchange. Our definition of affectionate touch receipt includes situations in which one receives an affectionate touch that a partner initiated or reciprocated. We also include static touch interactions such as lying next to one’s romantic partner with bodies touching or intertwined, as long as the partner initiated the touch or reciprocated the touch (e.g., by moving closer, by extending the duration of the touch). Providing affectionate touch strictly without receiving touch (e.g., rubbing one’s partner’s back without receiving a response) may also have benefits, but we argue that these benefits may operate through different pathways and are therefore not included in the current theoretical model.

Model of Affectionate Touch in Adulthood: Overview

The theoretical model that we propose (see Figure 1) depicts a causal relationship between receiving affectionate touch in adult close relationships and long-term beneficial outcomes in three domains of well-being: relational well-being, psychological well-being, and physical well-being. We focus on relational, psychological, and physical well-being outcomes because they broadly represent three domains in which an individual can thrive, and there is theoretical and empirical evidence that relational behaviors can affect each of these outcomes (e.g., Feeney & Collins, 2015; Thoits, 2011).

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Figure 1.

Theoretical model linking affectionate touch receipt to relational, psychological, and physical well-being.

Relational well-being includes satisfaction with and commitment to one’s relationship, low levels of conflict/distress in the relationship, and relational persistence; psychological well-being includes positive moods, subjective well-being, and a lack of psychological distress or disorder; and physical well-being includes avoiding illness/disease and associated pre-disease states, a lack of physical symptoms, and other indicators of physical functioning (Feeney & Collins, 2015). These well-being outcomes are bidirectionally linked (e.g., Cohen, 2004; De Vogli, Chandola, & Marmot, 2007; Hawkins & Booth, 2005; Loving & Slatcher, 2013; Proulx, Helms, & Buehler, 2007; Robles, Slatcher, Trombello, & McGinn, 2014; Umberson & Montez, 2010); therefore, the impact of touch on one outcome may be due, in part, to its influence on another outcome. For example, individuals who experience physical well-being may have fewer relational conflicts about their health maintenance, or individuals who have better relational well-being may experience more positive mood and have greater psychological well-being.

Despite these bidirectional links, we propose that affectionate touch receipt specifically affects each domain of well-being. Mechanistic paths linking affectionate touch to each long-term outcome are illustrated in Figure 1 and described in the following sections. One broad mechanism we will describe involves reducing daily stress and stress reactivity to promote well-being (Figure 1, Paths A, B). This pathway is based on the stress-buffering hypothesis, which states that social support may promote health by mitigating stress’ negative impact on health (Cohen & Wills, 1985). We propose that affectionate touch reduces daily stress and stress reactivity to prevent stress from detracting from well-being (i.e., affectionate touch buffers the negative effects of stress). However, we propose that affectionate touch also promotes well-being independent of stress. We describe two specific mechanistic pathways—a relational-cognitive pathway and a neurobiological pathway—that we propose will buffer stress to promote well-being and promote well-being independent of stress.

First, the interpretation of touch as affectionate (i.e., indicative of the touch provider’s love and care) may catalyze changes in the touch recipient’s relational and self-perceptions, which we refer to as relational-cognitive changes (Figure 1, Path C, D). Second, touch may induce changes in neurobiological systems that result from the touch experience itself, predominantly independent of any interpretation (Figure 1, Path G). We propose that these immediate outcomes of touch buffer stress (Figure 1, Paths E, H) and promote well-being independent of stress (Figure 1., Paths F, I) so that affectionate touch receipt will promote long-term well-being. In the following sections, we describe the relational-cognitive and neurobiological changes that result from affectionate touch receipt, and we provide theoretical and empirical evidence that these changes contribute to improvements in relational, psychological, and physical well-being.

In summary, Figure 1 outlines a normative mechanistic model to link receiving affectionate touch to long-term relational, psychological, and physical well-being. In elaborating this model, we also describe how the type of affectionate touch one receives as well as situational, personal, relational, and cultural factors might moderate the interpretation of touch to influence the relational-cognitive path (Figure 1, Path J). In addition, we consider whether touch’s interpretation could interrupt or modulate the neurobiological path (Figure 1, Path K), and we consider how physical properties of touch might influence the degree to which affectionate touch induces neurobiological changes (Figure 1, Path L). In the next several sections, we describe and provide evidence for each mechanistic link proposed in the model. First, we provide evidence that touch reduces stress; then, we explain how the immediate outcomes of touch (relational-cognitive changes and neurobiological changes) could affect long-term relational, psychological, and physical well-being both through their contributions to buffering stress and independent of stress.

Affectionate Touch Buffers Stress to Promote Well-Being (Figure 1, Paths A, B)

We propose that affectionate touch may promote well-being, in part, by reducing or preventing stress. Stress is well-known to undermine relational, psychological, and physical well-being, so a reduction in stress is both relationship- and health-protective (e.g., Uchino, 2006, 2009). In close relationships, stress reduces time spent together, worsens communication quality, interferes with relationship maintenance behaviors, and can lead to conflicts (Figure 1, Path B₁; e.g., Neff & Karney, 2004, 2009; Randall & Bodenmann, 2009). Stress also harms psychological (Figure 1, Path B₂) and physical (Figure 1, Path B₃) well-being because stressed individuals neglect health behaviors (e.g., exercise, balanced eating, meditating) and engage in harmful coping strategies (e.g., smoking, consuming alcohol, rumination; e.g., Cohen, Janicki-Deverts, & Miller, 2007). People who are chronically stressed are more likely to develop health problems and to have severe and persistent illnesses than less stressed individuals (e.g., Cohen et al., 2012; Cohen et al., 2007; Cohen, Tyrrell, & Smith, 1991; Kiecolt-Glaser, Marucha, Malarkey, Mercado, & Glaser, 1995; O’Leary, 1990). In addition, repeated hyper-reactivity of the physiological stress response can damage health by suppressing immunity, causing inflammation, and accelerating disease progression (e.g., Ader, Cohen, & Felten, 1995; Herbert & Cohen, 1993; Lovollo, 2005; McEwen, 1998; Segerstrom & Miller, 2004). For instance, a meta-analysis has shown prospectively that greater cardiovascular stress reactivity is associated with later cardiovascular health problems (Chida & Steptoe, 2010).

There is accumulating correlational and experimental evidence for the proposed theoretical link between receiving affectionate touch and reduced stress (Figure 1, Path A). Evidence suggests that affectionate touch is associated with lower daily stress (Burleson, Trevathan, & Todd, 2007; Floyd et al., 2009; Holt-Lunstad, Birmingham, & Light, 2008) and lower stress reactivity (Ditzen et al., 2007; Light, Grewen, & Amico, 2005). Researchers have used self-reported perceived stress and physiological stress markers as measures of stress in this research. Salivary alpha-amylase and salivary cortisol are biological markers of stress responses in the two primary stress systems, the autonomic nervous system (ANS) and the hypothalamic-pituitary-adrenal (HPA) axis, respectively (e.g., Berntson, Quigley, & Lozano, 2007). Alpha-amylase has been used as an indirect measure of sympathetic-adrenal medullary axis (SAM) activation in the ANS (Chatterton, Vogelsong, Lu, Ellman, & Hudgens, 1996; Nater & Rohleder, 2009), and it increases in response to stress (Nater et al., 2006; Nater et al., 2005). Cortisol is used as a biological marker of the level of activity in the HPA axis and has also been shown to increase reliably in response to stress (Kirschbaum & Hellhammer, 1994).

In daily diary studies, individuals had lower stress (i.e., lower levels of salivary cortisol) on days that they reported higher levels of affectionate touch (Ditzen, Hoppman, & Klumb, 2008), and affectionate touch receipt predicted fewer events perceived as stressful the following day (Burleson et al., 2007). An intervention study extended these correlational findings (Holt-Lunstad et al., 2008). Couples were randomly assigned to either a 4-week warm touch enhancement intervention (i.e., training in and daily practice of touch and massage techniques) or a control group in which couples reported their touch behaviors for 4 weeks but did not modify their behavior. Participants in the touch intervention group experienced greater declines in alpha-amylase (but not cortisol) over the intervention period than individuals in the control group. These studies suggest that receiving affectionate touch reduces naturally occurring daily stress, although future experimental research with an active control group (e.g., in which participants complete an alternative relationship enhancement intervention) would provide even stronger evidence.

Receiving affectionate touch also has been shown to attenuate stress reactivity during specific stressful experiences. In an experimental investigation of affection broadly, participants who were instructed to engage in an affectionate interaction with their romantic partner (i.e., affectionate touch while discussing a positive relational experience) before they completed a stressful speech task had lower heart rate and blood pressure reactivity to the task than participants who rested alone (Grewen, Anderson, Girdler, & Light, 2003). Affectionate touch, in particular, also has been shown to mitigate laboratory stress. Individuals who reported receiving more frequent hugs in their normal day-to-day relationship interactions had smaller heart rate increases during a stressful laboratory task than individuals who reported less frequent hugs (Light et al., 2005). Experimentally manipulated affectionate touch reduces stress reactivity as well (Ditzen et al., 2007). Specifically, participants who were randomly assigned to receive affectionate touch—a standardized neck and shoulder massage—from their partner prior to a stressful task had lower cortisol and heart rate reactivity during the task than participants assigned to a no-support condition in which they came to the lab alone. Participants who received touch also had marginally lower heart rate reactivity than participants who received another form of social support, verbal support, from their partners. Imagining affectionate touch receipt provides a similar stress-diminishing benefit; recalling and imagining supportive affectionate touch were effective to lessen the perceived stressfulness of a socially evaluative task, and it attenuated stress more effectively than imagining instances of a partner saying something supportive (Jakubiak & Feeney, in press-a).

Affectionate touch receipt also has been demonstrated to facilitate recovery after a stressor. The amount of affectionate touch an individual received from his or her partner after a stressful laboratory task (observationally coded) predicted reductions in distress, such that greater amounts of touch predicted greater reductions in distress (Robinson, Hoplock, & Cameron, 2015). Stress attenuation before or after a stressor may occur because affectionate touch from a close other reduces the stressfulness or threat of challenging situations. Evidence from one study supports this conjecture; under the threat of a painful electric shock, participants had less neural activation in brain areas associated with threat while holding their partners’ hands than when they were not holding hands (Coan, Schaefer, & Davidson, 2006).

Taken together, this extant research indicates that receiving affectionate touch from close others or having a history of physical affection has a protective effect on stress and stress reactivity in adulthood. Empirical evidence from infants and comparative research in animals provide additional, convergent evidence for this causal link. Infants who receive affectionate touch during infant stress tasks (i.e., “still-face” tasks in which parents create stress for an infant by being unresponsive) are protected from the psychological and physiological stress of the task (Feldman, Singer, & Zagoory, 2010; Jean & Stack, 2009). In addition, premature infants assigned to receive increased skin-to-skin contact from their caregivers have attenuated stress responses 10 years later compared with infants who received standard care (Feldman, Rosenthal, & Eidelman, 2014). Relatedly, grooming reduces stress for non-human primates and rodents (Dunbar, 2010; Harlow & Zimmerman, 1959; Weaver et al., 2004). For instance, rat pups that receive maternal licking and grooming experience changes in gene expression that result in reduced HPA responses to stress (Weaver et al., 2004).

We propose that the broad casual link between affectionate touch and lower stress (Figure 1, Path A) is explained by immediate relational-cognitive or neurobiological effects of touch receipt, which is why we indicate this path with a dotted line. We also propose that immediate relational-cognitive and neurobiological effects of touch may promote relational, psychological, and physical well-being directly, independent of stress. Next, we describe the relational-cognitive pathway, which begins with the touch recipient’s interpretation of the touch.

Relational-Cognitive Pathway (Figure 1, Paths C, D, E, F)

Touch’s Interpretation Promotes Relational-Cognitive Changes (Figure 1, Paths C, D)

Interpretation (Figure 1, Path C)

When an individual receives an affectionate touch such as a hug, kiss, or warm caress, the individual will likely interpret the meaning of the behavior. Normatively, an affectionate touch within a close relationship should be interpreted as an expression of the touch provider’s love and care because affectionate behaviors often—but not always—indicate true affection (Floyd, 2006). Touch also conveys a message that the relationship is close (Ben-Ari & Lavee, 2007); individuals ascribe greater intimacy to relationships in which they receive touch or observe touch compared with relationships with less touch (Burgoon, Buller, Hale, & deTurck, 1984; K. L. Johnson & Edwards, 1991; Mackey, Diemer, & O’Brien, 2000; Pisano et al., 1986; Thayer, 1986). This normative, positive interpretation of affectionate touch receipt leads to a series of relational-cognitive changes that we describe next.

Relational-cognitive changes (Figure 1, Path D; Figure 2)

When an individual receives an affectionate touch and interprets this touch as affectionate, a series of relational-cognitive changes may occur to link affectionate touch receipt to relational, psychological, and physical well-being. A detailed, elaborated depiction of these relational-cognitive changes is shown in Figure 2. First, receiving affectionate touch serves as a salient indicator of physical and emotional closeness to another person and therefore demonstrates social inclusion (Figure 2, Path A). It is considered a fundamental human need to form and maintain close relationships and to maintain proximity to significant others, and theorists propose that inclusion in close relationships permits individuals to thrive (e.g., Baumeister & Leary, 1995; Bowlby, 1969/1982, 1973; Coan, 2010; Deci & Ryan, 2000; Feeney & Collins, 2015). Receiving affectionate touch normatively indicates that one is included in a social group; the reminder of one relational connection may increase the salience of social inclusion broadly because memories of inclusion will be most accessible when individuals feel included currently (e.g., Singer & Salovey, 1988).

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Figure 2.

Relational-cognitive changes that result from affectionate touch receipt and its interpretation.

In addition, receiving touch that is interpreted as affectionate (i.e., indicating love and care) may promote felt security (Figure 2, Path B). Felt security includes immediate feelings of safety and calm, the global perception that one is cared for and accepted, and trust in one’s partner’s (the touch provider’s) continuing love, commitment, and responsiveness (e.g., Collins & Feeney, 2004). According to attachment theory, individuals experience felt security through repeated experiences in which others demonstrate availability, responsiveness, and care (e.g., Baldwin, 1992; Bowlby, 1969/1982, 1973; Bretherton, 1985; Carnelley & Rowe, 2007; Gillath, Selcuk, & Shaver, 2008; Sroufe & Waters, 1977). Affectionate touch demonstrates these attributes; thus, receiving affectionate touch (either spontaneously or in response to care seeking) is theorized to promote felt security in adulthood.

Indeed, preliminary research supports the idea that affectionate touch receipt promotes felt security in adulthood (e.g., Jakubiak & Feeney, in press-b; Mikulincer & Shaver, 2007b). Adults can be primed to feel secure by looking at pictures of individuals engaging in affectionate touch (Mikulincer & Shaver, 2007b). In addition, individuals who imagined touch experiences subsequently had greater accessibility of security-related words (e.g., calm, supported, loved, trusting) than individuals who instead imagined the details of a room, consistent with the activation of felt security (Jakubiak & Feeney, in press-b, Study 1). In another experiment, participants who were randomly assigned to receive affectionate touch from their romantic partners during a neutral television-watching task reported greater felt security after the task than participants whose partners interacted normally but refrained from providing touch (Jakubiak & Feeney, in press-b, Study 2). Finally, research has shown that when individuals receive affectionate touch from their romantic partners, they subsequently report that they feel “close to, secure with, cared for, and understood” by their partners (Debrot, Schoebi, Perrez, & Horn, 2013, p. 1376). Touch in infancy and childhood similarly promotes security (Anisfeld, Casper, Noyzce, & Cunningham, 1990; Duhn, 2010; Gurol & Polat, 2012; Hertenstein & Campos, 2001; Korja et al., 2008; Lowinger, Dimitrovsky, Strauss, & Mogilner, 1995; Miyake, Chen, & Campos, 1985; Weiss, Wilson, Hertenstein, & Campos, 2000).

Together, the perception of social inclusion and trust in one’s partner’s continuing love and responsiveness should foster the belief that support is available if needed (Figure 2, Paths C, D). Individuals expect that when they are included in social groups, others will provide support at a level commensurate with the relationship’s closeness (e.g., Arriaga, Goodfriend, & Lohmann, 2004; Coan, 2010). This perception that support is available is a powerful belief that is theorized to attenuate stress and facilitate autonomous behaviors, as described in later sections. Moreover, the perception that a touch provider will provide support is likely to be accurate because individuals are motivated to provide support when they feel greater closeness, and touch can be a gauge of the touch provider’s perceived closeness (e.g., Clark, Mills, & Powell, 1986; Feeney & Collins, 2001).

A second potential outcome of experiencing felt security (safety, feelings of acceptance, and trust in one’s partner’s continuing love, acceptance, and responsiveness) is the touch recipient’s willingness to increase dependence and closeness in the relationship (Figure 2, Path E). Individuals in close (especially romantic) relationships are interdependent—part of a unitary, cooperative unit—but they can choose to intensify or limit this dependence (e.g., Agnew, Van Lange, Rusbult, & Langston, 1998; Murray, Holmes, & Collins, 2006). According to self-expansion theory, individuals in close relationships expand their self-concepts to include close others’ resources, attributes, and goals (e.g., Aron, Aron, & Smollan, 1992; Aron, Aron, Tudor, & Nelson, 1991; Aron & Fraley, 1999). As their commitment and dependence increase, they become slower to differentiate their traits from their partner’s (e.g., Aron et al., 1992), they share their resources with their partners (e.g., Aron et al., 1991), they sacrifice for their partners (e.g., Van Lange et al., 1997), and they view their outcomes as linked to their partner’s outcomes such that one person’s failure or success affects both individuals (e.g., Aron, Mashek, & Aron, 2004). Individuals are simultaneously motivated to increase dependence so that they can experience the fulfillment of connection and to limit dependence because it can result in rejection, being taken advantage of, and other relational risks (Murray, Derrick, Leder, & Holmes, 2008; Murray et al., 2006). Research has demonstrated that individuals are only willing to risk increasing dependence (including experiencing positive regard for their partners) when they believe that their partners care for them and trust that their partners will continue to be loving and responsive (Murray, Holmes, & Griffin, 2000). If receiving affectionate touch leads to the appraisal that one’s partner can be trusted, individuals may choose to accept the risk of increasing closeness to and overlap with their partners.

Figure 1 indicates that relational-cognitive changes occur as a result of an affectionate interpretation of the touch receipt (i.e., an affectionate interpretation is important for linking affectionate touch receipt to relational-cognitive changes). However, it is possible that affectionate touch could lead a touch recipient to increase dependence without any conscious interpretation. Some research supports this possibility: A casual touch from a stranger increases compliance with the stranger’s requests, regardless of whether individuals are consciously aware that they have been touched (e.g., Crusco & Wetzel, 1984; Erceau & Guéguen, 2007; Fisher, Rytting, & Heslin, 1976; Guéguen, 2002). Because affectionate touch involves physical overlap between two individuals, it may also facilitate their cognitive overlap automatically. Theories of embodied cognition suggest that physical posture and movements can influence cognition because the mind and body are interconnected (Barsalou, 1999, 2010; Meier, Schnall, Schwarz, & Bargh, 2012; Niedenthal, Barsalou, Winkielman, Krauth-Gruber, & Ric, 2005). Indeed, research supports a bidirectional linkage between mind and body; for instance, individuals who experience physical instability also evaluate their relationships as more unstable (Forest, Kille, Wood, & Stehouwer, 2015). Extending this idea, physical overlap that occurs when an individual receives touch (by including another person into one’s body space) may facilitate psychological overlap because body states may activate a linked, dyadic self-concept. Cross-sectional research has demonstrated that touch in romantic relationships correlates positively with self-reported feelings of psychological self–other overlap (Ledbetter, 2013).

In sum, receiving affectionate touch may lead to immediate relational-cognitive changes and downstream processes that ultimately link receiving touch to long-term relational, psychological, and physical well-being. In the following two sections, we describe how these relational-cognitive changes may protect relational, psychological, and physical well-being indirectly by buffering stress’ negative impact on well-being (Figure 1, Paths E, B) or by promoting well-being directly (Figure 1, Path F).

Neurobiological Pathway (Figure 1, Paths G, H, I)

We propose another mechanistic pathway, a neurobiological pathway, that acts complementary to the relational-cognitive pathway to promote well-being when adults receive affectionate touch from close others. Empirical evidence suggests that the physical encoding or processing of a touch experience leads to changes in biological systems. The immediate neurobiological changes that result from receiving and sensing touch (Figure 1, Path G), primarily independent of any interpretation, may link to the neurobiological systems responsible for heightening or dampening stress reactions (Figure 1, Path H) or may link to well-being outcomes directly (Figure 1, Path I).

Recent neurobiological evidence suggests that humans have a specialized neural pathway to detect and process socially relevant touch (e.g., Walker & McGlone, 2013). Unlike touch to identify or manipulate objects, socially relevant (and affectionate) touch tends to be soft, slow, stroking touch on hairy skin (e.g., Morrison, 2012). It is coded and transmitted by a class of unmyelinated peripheral nerve receptors called C tactile afferents (CT afferents; for example, Morrison, 2012; Morrison, Löken, & Olausson, 2010) and is especially reinforcing (e.g., Gordon et al., 2011; Löken, Wessberg, Morrison, McGlone, & Olausson, 2009; Olausson et al., 2002). Stimulation of these CT afferents generates a pleasurable and rewarding experience because CT afferents activate social-processing, emotion-sensitive, and reward areas of the brain, including the posterior insular cortex, orbitofrontal cortex, superior temporal sulcus, pregenual anterior cingulate cortex, and the amygdala (e.g., Gordon et al., 2011; Lindgren et al., 2011; McGlone et al., 2012; Walker & McGlone, 2013). Based on this evidence, researchers have argued that the skin is not only a sensory organ but also a social one, tuned to code for interpersonal interactions and make these interactions rewarding (e.g., Morrison et al., 2010; Walker & McGlone, 2013). Affectionate touch receipt, likely encoded by CT afferents in many cases, may both buffer stress and promote well-being independent of stress through neurobiological changes that occur after touch is encoded.

There is some evidence that this neurobiological path is a necessary addition to the relational-cognitive path because receiving physical contact itself affects well-being even when it is not provided by a close friend or partner. Specifically, research on the effects of massage has shown that people experience health benefits of physical massage from strangers, individuals who are not considered close others or expected to provide support if needed (e.g., Lindgren et al., 2011; Moyer, Rounds, & Hannum, 2004). A meta-analysis across 144 studies provided evidence that receiving massage can reduce state and trait anxiety, state blood pressure, state heart rate, trait depression, and pain (Moyer et al., 2004), and massage has also been shown to reduce depression and to enhance immune function (Billhult, Lindholm, Gunnarsson, & Stener-Victorin, 2009; see Field, 2010, for a review). Relatedly, research on therapeutic touch in nursing contexts suggests that patients who receive touch experience less anxiety, physiological stress, and pain than patients who do not receive touch (e.g., Aghabati, Mohammadi, & Esmaiel, 2008; Busch et al., 2012; Papathanassoglou & Mpouzika, 2012; Vannorsdall, Dalquist, Pendley, & Power, 2004). Holding a soft, inanimate object also has positive effects. The negative effects of social exclusion and thinking about one’s death were reduced for individuals who held a teddy bear (Koole, Sin, & Schneider, 2013; Tai, Zheng, & Narayanan, 2011). These beneficial outcomes of receiving affectionate touch from a non-close other may be explained, in part, by a neurobiological pathway that buffers stress and promotes well-being.

Two important potential neurobiological changes that could link affectionate touch receipt to improvements in well-being outcomes are oxytocin and endogenous opioids because both are triggered by affectionate touch (Figure 1, Path G) and both interface with stress systems and can downregulate stress responses (Figure 1, Path H; e.g., DeVries, Glasper, & Detillion, 2003; Diamond, 2001). In addition to buffering the negative effects of stress, preliminary evidence suggests that oxytocin and endogenous opioids may promote approach tendencies and may therefore link to well-being independent of stress (Figure 1, Path I).

Moderators of the Normative Model (Figure 1, Paths J, K, L)

The normative model linking affectionate touch receipt to long-term relational, psychological, and physical well-being may be affected by the context in which touch is received, the type of affectionate touch behavior, or physical properties of the touch. Next, we describe several factors that may alter the interpretation of touch as affectionate (Figure 1., Path J) to shape the relational-cognitive pathway. In addition, although we do not expect that an affectionate interpretation is necessary for neurobiological changes to occur, we describe how touch’s interpretation may modulate the neurobiological pathway (Figure 1, Path K). Finally, physical properties of touch may moderate the neurobiological changes resulting from affectionate touch receipt (Figure 1., Path L). The following sections elaborate on these potential moderators that we expect will shape the normative theoretical model.

Empirical Support for Links Between Affectionate Touch Receipt and Well-Being Outcomes in Adulthood

Although the effects of affectionate touch in adult close relationships have been relatively unstudied, there is some evidence in support of the overall model that affectionate touch receipt causes improvements in relational, psychological, and physical well-being. There is accumulating evidence demonstrating associations between affectionate touch and well-being for which causality cannot be inferred, and there are a few recent experimental studies in which affectionate touch has been manipulated. Next, we briefly review and evaluate the extant evidence that affectionate touch receipt in adulthood promotes relational well-being (e.g., relationship satisfaction, commitment, intimacy), psychological well-being (e.g., positive mood, reductions in anxiety), and physical well-being (e.g., lower blood pressure, fewer somatic symptoms).

Roadmap for Future Research

Our goals in proposing this theoretical framework are to generate research on affectionate touch in adult close relationships and to establish the processes through which affectionate touch is likely to have its effects. A first priority for future research is to use rigorous experimental methods to establish conclusively that affectionate touch receipt improves and/or protects relational, psychological, and physical well-being. Additional intervention studies will bolster the primarily correlational extant research linking affectionate touch to important domains of well-being and will allow for causal inferences. The existing longitudinal studies that provide support for a link between affectionate touch receipt and well-being (e.g., Cohen et al., 2015; Debrot et al., 2013; Muise et al., 2014) must be supplemented by experimental research that eliminates confounding variables. For instance, individuals who receive frequent affectionate touch may have less time pressure, be more financially stable, have partners with greater investment, or differ in any number of ways from individuals who receive less affectionate touch, and it may be these factors that promote long-term outcomes. To establish that affectionate touch receipt causally predicts relational, psychological, and physical well-being, individuals must be randomly assigned to receive affectionate touch in future experimental studies. Also, appropriate control groups must be used to establish that observed effects are specific to affectionate touch (and not just any positive relationship intervention).

Interventions to increase affectionate touch may be difficult to administer because instructions to change touch behavior may alter couples’ desires to engage in touch or change the interpretation of the touch. Therefore, future research should not only test the impact of touch on well-being experimentally but also identify ideal intervention protocols to assess touch’s benefits. It may be necessary to have partners provide affectionate touch to an individual without the individual’s awareness of the instructions so that the affectionate touch manipulation does not produce a placebo effect or make the relationship especially salient. One previous study has effectively recruited the partner as a confederate to provide affectionate touch in this way (Jakubiak & Feeney, in press-b, Study 2). Alternatively, a well-matched control condition in which participants receive another type of support provision or relationship intervention could provide an optimal comparison to identify the effects of receiving affectionate touch, in particular.

Future experimental studies also should assess immediate indicators of relational, psychological, and physical well-being (e.g., positive relational behaviors and perceptions, positive affect, subjective well-being, wound-healing, infection symptoms) as well as broad, long-term well-being outcomes (e.g., relational commitment and persistence, psychological symptoms and disorders, atherosclerosis, cardiovascular disease). Investigating both immediate and long-term outcomes can inform whether affectionate touch is beneficial over time (as we propose in our theoretical model) or whether benefits are relatively short-lived. Additional prospective, non-experimental studies to assess how receiving affectionate touch relates to changes in well-being over time for healthy adults will also clarify the outcomes of affectionate touch receipt and corroborate experimental research. Future research also should quantify the size of these effects to determine affectionate touch’s intervention potential.

Another important direction for future research is to test the proposed mechanisms linking affectionate touch to well-being directly. There is strong evidence indicating that affectionate touch reduces stress (e.g., Ditzen et al., 2007); however, other model propositions have not been tested. In particular, evidence that affectionate touch receipt is sufficient to encourage relationship-protective or health-protective behaviors must be accumulated. The existing evidence linking affectionate touch receipt to relational well-being commonly measures perceptions of one’s relationship (e.g., Muise et al., 2014); future research should assess whether touch motivates individuals to protect their relationships by enacting pro-relational behaviors such as sacrificing and cooperating. Whether affectionate touch receipt promotes self-care behaviors (by increasing self-efficacy for these behaviors or to benefit one’s partner in the long term) is also untested and should be investigated. Evidence for the proposed biological mechanisms is also in an inchoate state. Additional research is needed to explicate how, and under what contexts, affectionate touch increases oxytocin and endogenous opioids in humans. Furthermore, a comprehensive explanation of the role of oxytocin and endogenous opioids to promote relational, psychological, and physical well-being is necessary to conclusively link touch to well-being through a biological pathway.

The potential moderators that we propose may shape the normative model should also be tested, to establish the boundary conditions of touch’s effects. In addition to the ones we elaborated, other factors that may also affect touch’s interpretation (e.g., gender, type of close relationship; K. L. Johnson & Edwards, 1991; Miller, Denes, Diaz, & Ranjit, 2014; Stier & Hall, 1984) can be explored. Future research can assess these and other aspects of the proposed model to test its tenability and comprehensiveness.

Another important avenue for future research that follows from the proposed model is to test the relative contributions of the relational-cognitive pathway (Figure 1, Paths C, D) and the neurobiological pathway (Figure 1, Path G) to explain the links between affectionate touch receipt and well-being. We propose that the psychological interpretation of touch and the physical instantiation of touch both contribute to improvements in well-being through the relational-cognitive and neurobiological pathways, respectively. However, future research should address whether these pathways are equally important and to what extent these pathways interact. We expect that both pathways are operative and influential but that the relational-cognitive pathway and the interpretation of touch may be most important in producing long-term relational, psychological, and physical well-being outcomes. For adults, physical sensations are imbued with meaning, and that meaning can shape the physical experience. In other words, the way that individuals think, feel, and behave in their relationships may depend more on their interpretations of the physical and social environment than on the environment itself. Research on the power of reappraisal to shape physiological, emotional, and behavioral responses supports this supposition (e.g., Beltzer, Nock, Peters, & Jamieson, 2014; Jamieson, Mendes, Blackstock, & Schmader, 2010).

Future research also can assess whether the relational-cognitive and neurobiological effects of receiving affectionate touch produce an additive or synergistic effect to make affectionate touch receipt more potent than receiving other enactments of support or affection. If, as proposed, affectionate touch receipt affects both relational-cognitive mechanisms and neurobiological mechanisms, it may be an especially effective support behavior to attenuate stress and promote well-being because of the additive effects of these two mechanisms. There is experimental support for this possibility; social support is more effective to reduce stress when paired with intranasal oxytocin administration (Heinrichs et al., 2003). Specifically, participants who were randomly assigned to receive social support plus intranasal oxytocin before a social stressor had greater feelings of calm and less anxiety, and had lower levels of salivary cortisol than participants who experienced either intranasal oxytocin or social support alone. Affectionate touch support may naturally combine relational-cognitive (e.g., perception of social support availability) and neurobiological (e.g., oxytocin) pathways for added effect.

Indeed, previous laboratory research has demonstrated a superior stress-attenuating effect of receiving affectionate touch support compared with receiving verbal support. Affectionate touch reduced physiological reactivity to a lab stressor better than verbal support (Ditzen et al., 2007), and imagined affectionate touch reduced subjective stress and pain during lab stressors better than imagined verbal support (Jakubiak & Feeney, in press-a). Future research should build on these initial studies to assess whether touch can be a more effective enactment of social support outside the lab and during more serious and persistent stressors. In addition, future research can investigate whether affectionate touch promotes relational, psychological, and physical well-being better than other ways of communicating affection (see Floyd, 2006).

Concluding Statement

Throughout the life span, individuals engage in affectionate touch with close others. We have proposed a theoretical mechanistic model to explain how receiving affectionate touch in adult close relationships may promote relational, psychological, and physical well-being in adulthood (Figure 1). The theoretical perspective we advance may contribute to understanding how inclusion in close relationships “gets under the skin” to benefit individual well-being and how an individual’s specific relational behaviors promote relational well-being. We proposed that affectionate touch receipt is a relational behavior that results in a cascade of immediate relational-cognitive changes (e.g., perceiving inclusion and support availability, increasing dependence) and neurobiological changes (e.g., increases in oxytocin, endogenous opioids) that may protect and enhance relational, psychological, and physical well-being. We reviewed the direct and indirect evidence for the proposed model, and we outlined an agenda for future research on touch in adult close relationships. Our hope is that this theoretical perspective will provide a foundation for future work in this promising, yet undeveloped, research area.