The Role of Oxytocin in Human Affect: A Novel Hypothesis

All hypotheses in the reviewed studies were derived from three major behavioral theories of oxytocin: affiliation, social salience, and social approach.

“All of our hypotheses were derived from the three major behavioral IN-OT theories (i.e., OT as a hormone of affiliation (16); OT as a hormone of social salience(15)and OT as a hormone of social approach (17)).”

OXT often facilitates approach behaviors, although this can be context- and person-dependent.

“The prosocial actions of OXT often involve facilitation of approach behaviors (Hurlemann et al., 2010;Kemp and Guastella, 2011;Striepens et al., 2011), although this can be context-and person-dependent (Bartz et al., 2011)”

Oxytocin can also influence social interactions between peers and strangers and appears to play essential roles in the identification and interpretation of social information.

“Oxytocin can also influence social interactions between peers and strangers and appears to play essential roles in the identification and interpretation of social information.”

Oxytocin improves the detection and classification of positive social and emotional stimuli but not for negative stimuli.

“For instance, oxytocin improves the detection and classification of positive social and emotional stimuli but not for negative stimuli (see Kemp and Guastella, 2011).”

Oxytocin administration has been shown to orient attention toward faces, particularly the eye region.

“For instance, oxytocin administration has been shown to orient attention toward faces, particularly the eye region (see Bartz et al., 2011, Kemp and Guastella, 2011).”

The observed reductions in right amygdala activation during the presentation of both negatively and positively valenced stimuli after intranasal OT treatment and the additional main effect of treatment on amygdala reactivity to shapes are consistent with the hypothesis that intranasal OT delivery has two levels of action: a bottom-up effect that facilitates approach-related behaviors and a top-dow

“The observed reductions in right amygdala activation during the presentation of both negatively and positively valenced stimuli after intranasal OT treatment and the additional main effect of treatment on amygdala reactivity to shapes -which did not reveal any posthoc differences between groups but were in the same direction as the other analyses -are consistent with the hypothesis that intranasal”

Converging evidence suggests that oxytocin increases social salience and approach-related behaviors, regardless of valence.

“with converging evidence suggesting that oxytocin increases social salience30 and approach-related behaviors,31 regardless of valence.”

OT plays an essential role in the regulation of social behavior and social cognition in animals and humans, often facilitating pro-social and approach behaviors.

“OT has been suggested as playing an essential role in the regulation of social behavior and social cognition in animals and in humans (see Meyer-Lindenberg et al., 2011;Van IJzendoorn and Bakermans-Kranenburg, 2012 for reviews), often facilitating pro-social and approach behaviors (Kemp and Guastella, 2011;Striepens et al., 2011).”

A more dominant theory suggests that OT increases approach toward and decreases avoidance of social stimuli.

“A more dominant theory of OT's effects on social cognition suggests that it increases approach toward and decreases avoidance of social stimuli [20], [18], [21], [22]”

The finding that intranasal OT did not enhance approach or decrease avoidance to emotional faces fails to support the theory that OT increases approach to social stimuli and decreases avoidance.

“thus failing to support the theory that OT increases approach to social stimuli and decreases avoidance [21].”

The theory that OT increases approach to social stimuli and decreases avoidance.

“the theory that OT increases approach to social stimuli and decreases avoidance [21].”

Within the general approach-avoidance hypothesis of oxytocin, oxytocin's complex behavioral effects are considered to be rooted in its modulation of the salience of personally relevant and emotionally evocative stimuli not necessarily restricted to social contexts.

“More specifically, within this extended overarching framework, OT’s complex behavioral effects are considered to be rooted in its modulation of the salience of personally relevant and emotionally evocative stimuli not necessarily restricted to social contexts (Harari-Dahan and Bernstein, 2014; cf. Kemp and Guastella, 2011 for the social-approach/withdrawal hypothesis and Shamay-Tsoory and Abu-Akel”