In everyday life, people are interacting with the Internet. The emergence of this phenomenon has been positively contributing to the rapid development of our society in the last decades. However, negative reports about excessive usage are coming to the surface and questions about potential negative consequences are being raised. Internet addiction (IA) has been suggestedas a new type of disorder. There is a new field of research emerging with the aim to investigate its nature. This review compiles the most relevant literature on neuroimaging techniques used to identify the underlying neurobiological mechanisms of IA. Based on identified comorbidity between IA and attention-deficit hyperactivity disorder (ADHD), a comparison between the neural correlates of IA and ADHD is attempted, in order to illustrate the importance of bringing more attention to IA. The findings present structural, functional and neurochemical alterations in brain regions associated with emotional processing, cognitive control and reward processing. Similarities between the two disorders interms of structural and functional alterations in regions associated with emotional processing and cognitive control are highlighted.Limitations regarding lack of consensus of the operational definition, narrow selection criteria of participants and a need for subcategories inside the term IA are pointed out. The thesis concludes that as of now the discovered alterations may be considered as biological markers underlying the disorder and IA is a field of research worthy of more attention.