Internet game overuse linked to impaired feedback processing for symbolic reward

Brain scans from young men in South Korea provide evidence that compulsive online video game players do not process some rewards efficiently.

The study, published in Frontiers in Psychiatry, found that problematic gaming was associated with impaired learning in a particular situation. Compulsive gamers showed reduced sensitivity to symbolic positive feedback.

“As the infrastructure of internet is advancing, more people become players who enjoy the internet game world, where online playmates are available day and night, and a finger/hand movement decision can be immediately rewarded with accumulating points,” explained study author Eunjoo Kang of Kangwon National University.

“In a country like South Korea, which is one of the world’s most wired places, roughly one in ten adolescents (usually male) are reported to be addicted to Internet gaming. Unfortunately, they often experience falling academic performance, along with social isolation in the offline world, which concerns their parents, as well as the general public.”

“Past research shows that, like substance abuse, those with internet gaming disorder have problems in dealing with reward, being either too sensitive or impaired in information processing,” Kang explained to PsyPost.

“Here we investigated how individual differences affect efficiency in processing motivational or emotional events in learning and memory. We asked whether internet game overuse affects brain responses to reward or penalty, and/or the ability to use these outcomes to learn to repeat those responses that led to rewards, and avoid those that resulted in penalties. We also evaluated the possibility that the effects of internet gaming overuse depend on the motivational saliency of the rewards and penalties.”

The study compared 18 young men who displayed signs of problematic gaming overuse to 20 young control participants. All the participants in the study completed an association learning task while undergoing a an fMRI brain scan.

The learning task provided the participants with various types of feedback. Sometimes correct answers resulted in a monetary reward, while incorrect answers resulted in a monetary penalty. Other times, correct answers resulted in only a symbolic reward and incorrect answers resulted in a symbolic penalty. (The participants were shown the Chinese symbols right and wrong, respectively.)

The researcher found that symbolic positive feedback had less of an effect on participants with internet gaming disorder compared to the control participants.

“If you are considering getting involved in internet-games, you’d better be careful about touching that gamepad,” Kang told PsyPost. “You might get hooked if the hedonic processing part of your brain is much more excited by concrete incentives, such as a monetary reward, than for a symbolic reward, such as simple feedback indicating that your response was correct.”

The researchers also observed differences in how the brain responded to the learning task.

“Each individual differs in brain responses for monetary reward, relative to symbolic reward, in a brain region called the ventral striatum, which is known for hedonic (i.e., pleasure) processing,” Kang said. “Our data suggests that the greater the bias of the ventral striatum response toward concrete (relative to symbolic reward), the more likely the individual is to become addicted to internet gaming.”

“Extensive exposure to internet gaming may also impair cognitive performance that depends on learning from symbolic rewards. We found that individuals with internet game overuse did not process symbolic reward efficiently, consistent with relatively low activation of a frontal lobe region called the ventromedial prefrontal cortex, which is known to be involved in value processing.”

“Learning from symbolic feedback is important, because the majority of our positive feedback is symbolic, such as verbal praise, subtle encouragements, or self-monitoring of one’s progress, rather than from concrete rewards such as money or candy,” Kang said. “By normal adulthood, we all have learned to be motivated without explicit incentives. However, extensive indulgence in internet video gaming may interfere with the ability to development of self-motivation in adolescents.”

Like all research, the study had some limitations.

“Our participants were male college students with internet gaming overuse who were not formally diagnosed for clinical internet game disorder. Yet we found interesting differences between them and those without overuse in how the brain responds to reward,” Kang remarked.

“These otherwise normal college students showed some personality aspects associated with other addictions, such as relatively high depression, anxiety, and impulsivity, all of which are also known to affect reward processing.”

“But we are not sure if these differences are associated with risk factors of internet-gaming disorder, or are the consequences of heavy internet game usage (i.e., does heavy use of internet games rewire the brain?),” Kang said. “Only longitudinal studies will be able to dissociate the effect of those psychiatric comorbidity factors and internet gaming effects on feedback processing.”

The study, “Impaired Feedback Processing for Symbolic Reward in Individuals with Internet Game Overuse“, was co-authored by Jinhee Kim and Hackjin Kim.