A 24 hours changes and reactivity in heart-rate variability during the Iowa gambling task may predict Internet addiction: Weak top-down control among young students

This study evaluated the influence of excessive Internet use on heart rate variability(HRV) using a 24 hour electrocardiogram (ECG) and examined acute changes during the Iowa gambling task (IGT) and a computer game. We recruited 35 men, and divided them into high-risk Internet addiction (HIA) and low-risk Internet addiction (LIA) groups based on their Internet addiction test scores. The ECG was recorded continuously for 24 hour using a wearable sensor and during the IGT and each participant’s preferred game using a standard ECG system. Multiple psychometric tests were conducted. The HIA group exhibited more clinically significant depressive symptoms, and higher self-reported scores for anxiety, and autistic tendencies than the LIA group. Differences were observed in the 24 hour high-frequency (HF) band power and standard deviation of the normal-to-normal (SDNN) inter-beat interval between the two groups. The tendency toward Internet addiction differed by age; thus the participants were divided into two groups according to age to examine the differences between them. In the IGT, younger participants exhibited a reduced HF response. Young people’s impulse control, and the autonomic nervous system are maturing, and autonomic responses to tasks need to be assessed in an age-appropriate manner.