International attention for brain research in Siegen
International attention for brain research in Siegen
The research of Siegen psychology professor Dr. Tim Klucken on reward processes in the brain has received international attention: A scientific article by his team has been named a "Top Viewed Article 2025" by the scientific publisher Wiley in the renowned journal "Human Brain Mapping". This makes the study one of the most widely read articles of the year in one of the leading international journals for brain and neuroscience. Together with the Department of Psychotherapy and Systems Neuroscience at the University of Siegen, the Siegen psychologists investigated how people associate certain signals with rewards - and which cues trigger particularly intense brain reactions. The focus was on pornographic content, monetary incentives and computer game scenes.
"We are delighted to receive this award because it shows that the University of Siegen's research is also being recognized internationally," says Klucken, who conducts research at the University of Siegen into emotions, mental disorders, learning processes, media use and addiction, among other things. The first author of the award-winning article is doctoral student Kseniya Krikova from Klucken's team.
For the study, the team used functional magnetic resonance imaging (fMRI) to visualize brain activity. 31 healthy young men were shown geometric symbols, each announcing a specific reward: some stood for cash prizes, others for screenshots from computer games or pornographic content. The participants quickly learned which symbols were associated with which rewards. Even displaying the neutral symbols subsequently triggered measurable activation in relevant brain regions.
"It is astonishing that even a simple geometric symbol can trigger desire and pleasure in the brain," explains Klucken. "Our results show how quickly the human brain learns to associate certain cues with rewards."
The reaction to pornographic content was particularly clear: The associated symbols activated the reward system more strongly than money or gaming stimuli.
"Pornographic content apparently has a particularly high reward value," says Klucken. "Similar to food or sexuality, such stimuli are considered primary rewards in evolutionary terms. Money or gaming, on the other hand, receive their meaning more strongly through learning or social attributions and produced weaker neuronal effects in our experiment."
The study was conducted as part of a transregional research group on behavioral addictions, which has been funded by the German Research Foundation (DFG) since 2021. The focus is on problematic and excessive forms of use of computer games, online shopping, internet pornography and social media. "Problematic internet use is a relatively new phenomenon that has not yet been researched as intensively. Our aim is to better understand what role reward and learning processes play in the brain when consuming digital media," says Klucken. The different reactions to different stimuli could help to understand why some digital content has a higher addictive potential than others.
In a second part of the study, the research team investigated whether people with problematic media use process certain stimuli differently than people without corresponding symptoms. The results are due to be published shortly.
