AUTONOMIC STRESS REACTIVITY AND CRAVING IN INDIVIDUALS WITH PROBLEMATIC INTERNET USE

The link between autonomic stress reactivity and subjective urge/craving has been less systematically examined in behavioral addictions than in substance use disorders. The present study investigated whether problematic Internet users (PIU) show enhanced autonomic stress reactivity than non-PIU, indexed by lower Heart Rate Variability (HRV) and higher Skin Conductance Level (SCL) during the Trier Social Stress Test (TSST), and whether greater reactivity is related to stronger urge/craving. Based on their Internet Addiction Test scores, participants were divided into PIU (N = 24) and non-PIU (N = 21). Their heart rate and skin conductance were continuously recorded during baseline, the TSST, and recovery. HRV and SCL reactivity during the TSST were measured as autonomic indices of the stress response. “Urge to be online” ratings were collected using a Likert scale before and after the TSST. The SDNN, an overall measure of HRV, was significantly lower in PIU than non-PIU during baseline, but not during the TSST and recovery. Furthermore, only among PIU a significant negative correlation emerged between SDNN during recovery and urge ratings after the test. No group differences emerged for SCL. Our findings suggest that problems in controlling one's use of the Internet may be related to reduced autonomic balance at rest. Moreover, our results provide new insights into the characterization of craving in PIU, indicating the existence of a relationship between craving for Internet usage and reduced autonomic flexibility.