Addictive behaviors share clinical, genetic, neurobiological and phenomenological parallels with substance addictions. Despite the prevalence of compulsive sexual behaviors, particularly problematic pornography use (PPU), how neuroendocrine systems relate to PPU is not well understood. Preclinical studies demonstrate alterations in oxytocin and arginine vasopressin (AVP) function in animal models of addiction, but no human study has tested their involvement in PPU.
Participants included 122 males; 69 reported PPU, and 53 were demographically-matched participants without PPU. Plasma oxytocin and AVP levels and oxytocin-to-AVP balance were measured at baseline. Salivary oxytocin was assessed at baseline and in response to four videos depicting neutral/positive social encounters. Participants reported on empathy and psychiatric symptoms.
Baseline plasma AVP levels were elevated in men with PPU, and the ratio of oxytocin-to-vasopressin suggested AVP dominance. Men with PPU reacted with greater oxytocin increases to presentation of neutral/positive social stimuli. Decreased empathic tendencies were found in men with PPU, and this reduced empathy mediated links between oxytocin and pornography-related hypersexuality. Structural equation modeling revealed three independent paths to pornography-related hypersexuality; two direct paths via increased AVP and higher psychiatric symptoms and one indirect path from oxytocin to pornography-related hypersexuality mediated by diminished empathy.
Findings are among the first to implicate neuropeptides sustaining mammalian attachment in the pathophysiology of pornography-related hypersexuality and describe a neurobiological mechanism by which oxytocin-AVP systems and psychiatric symptomatology may operate to reduce empathy and lead to pornography-related hypersexuality.
Addicted individuals often demonstrate relatively automatic action tendencies in response to addiction-related stimuli, whereby they approach rather than avoid addictive stimuli. This study assessed whether an approach bias for erotic stimuli exists among heterosexual college-aged males who report using pornography.
We tested 72 male undergraduate students using an approach–avoidance task employing erotic stimuli, during which participants were instructed to push or pull a joystick in response to image orientation. To simulate approach and avoidance movements, pulling the joystick enlarged the image and pushing shrunk the image. Frequency and severity of pornography use was assessed using a Brief Pornography Screener and the Problematic Pornography Use Scale (PPUS).
Participants demonstrated a significant approach bias for erotic stimuli as compared to neutral stimuli, and this approach bias significantly correlated with pornography-use measures. Moreover, individuals with problematic pornography use (as classified by the PPUS) showed more than double the approach bias than did non-problematic users.
Discussion and conclusion
The observation of cognitive biases for erotic stimuli in individuals with problematic pornography use indicate similarities between behavioral and substance addictions.