As a result of a previous correlational study looking at screen habits, the psychologist concluded that participants who spent more time on digital screens had longer reaction times on attention tasks. Other previous research has also shown that intensive screen stimulation has an immediate impact on cognitive speed. In a follow-up study, the psychologist designed an experiment to investigate further the effect of screen exposure nature on reaction times. They randomly selected 20 students from a local college. There were two conditions: Condition 1 – the students were invited to a psychology research room and were instructed to play a fast-paced video game on a smartphone for one hour. Fifteen minutes after finishing, each student was tested on a computerized reaction-time program to measure their average response speed across 10 trials. Condition 2 – the same 20 students were invited back to the research room a week later. This time they were instructed to read a printed paper book for one hour. Fifteen minutes after finishing, each student was tested again using the same reaction-time program.