What was the first step taken in the brain scan procedure in Raine's study?

• A. Participants received their medication
• B. CPT practice trial
• C. Injection of a tracer
• D. Measurements of heart rate

Answer: (B)

In Raine's study, the first step taken in the brain scan procedure involved conducting a Continuous Performance Test (CPT) practice trial. This trial was essential for familiarizing participants with the task they would be performing during the brain scanning process. The CPT is designed to assess attention and impulsivity, which are relevant to the research focus on brain activity linked to these cognitive functions. By completing the practice trial, participants could better understand their role in the study, ensuring the data collected during the actual brain scan was more reliable and valid.

The option to receive medication, injection of a tracer, or measurements of heart rate would occur at different stages of the study, with each having specific purposes related to brain imaging and physiological monitoring, but none of these was the initial step in the procedure. This highlights the importance of preparing the subjects through a practice trial to optimize their performance during the subsequent testing phases.