Participants in the Study: One Thousand Volunteers from Adam Mickiewicz University, Poznan

The study conducted at Adam Mickiewicz University in Poznan involved 1,000 volunteers who participated in two separate studies. The participants were recruited through electronic advertisements and had to meet specific criteria, such as being adults with no history of neurological disorders or hearing problems. After exclusions, the final sample consisted of 920 adult participants, with varying demographics and educational backgrounds.

In Study 1, participants were divided into two groups based on the type of test they chose. The groups did not differ significantly in basic characteristics but showed differences in education and the device used for the study. The group exposed to stimulating sounds performed slightly better in baseline tests compared to the neutral sounds group.

In Study 2, participants were randomly assigned to five groups based on the type of acoustic stimulation. Again, the groups did not differ significantly in basic characteristics, but differences were observed in education levels. The group exposed to 5 Hz acoustic stimulation scored lower in the Matrix Reasoning Item Bank test compared to the control group.

The participants were ensured of their anonymity and provided written consent before the study. The study was approved by the Ethics Committee of the Faculty of Educational Studies and conducted in accordance with ethical principles.

Various cognitive tests were conducted, including the Raven’s Progressive Matrices test and the Matrix Reasoning Item Bank test, to evaluate fluid intelligence and abstract reasoning. Acoustic stimuli, including binaural beats and classical music, were used in the study.

Overall, the study provided valuable insights into the effects of different types of acoustic stimulation on cognitive performance and highlighted the importance of considering individual differences in cognitive research.