Brain reward system and its volumetric investigations in alcohol addiction

Alcoholic beverages are as old as human history and have been used for a wide variety of purposes. Sometimes its use is encouraged for cultural and religious reasons, and sometimes it is prohibited. It has only recently been possible to define the harmful use of alcoholic beverages and accept it as a disease. Alcohol use disorder is a diagnosis that includes both addiction and abuse concepts that entered our lives with the DSM-5. The prevalence of AUD is 8.1% in men and 1.7% in women in our country, and it is getting more and more common. Biopsychosocial factors play a role in the etiology of AUD. The system, which includes many cortical and subcortical structures, which we call the brain reward system, plays an active role in the initiation and maintenance of AUD. In the thesis we presented, 15 cases with AUD and 17 healthy controls were compared in terms of total white matter, total gray matter, nucleus accumbens, amygdala and hippocampus volumes. The volume of the right hippocampus was found to be significantly decreased in the AUD group. While total white matter volume and right amygdala volume were increased in the AUD group, the other regions examined were found to be lower in the AUD group. However, these volumetric changes were not at a level to create a statistically significant difference. Different findings have been reported in the literature regarding the examined region volumes. Our study found volumetric changes consistent with most previous studies. However, due to limitations such as the small number of participants, it was insufficient to present statistically strong findings. Designs with more participants and minimizing the influence of the evaluators are required so that the study outputs to be clearer and generalizable.