A cognitive scientist wanted to investigate whether drinking ceremonial matcha green tea or single-origin black filter coffee leads to a greater improvement in psychomotor vigilance. The scientist could not find any published literature comparing the long-term daily effects of these two specific beverages on cognitive performance directly.
The scientist used a matched-pairs design, pairing 32 healthy adult participants based on their age and baseline reaction times. One participant from each pair was allocated to Group A, and the other to Group B.
The study lasted for 14 days, during which all participants agreed to abstain from all other caffeinated beverages or stimulants.
At the start (Day 0) and at the end (Day 14) of the study, all participants completed a computerized Psychomotor Vigilance Task (PVT). The scientist then calculated the change in mean reaction time (in milliseconds) for each participant.
Write a suitable hypothesis for this study.
689 exam-style questions on AQA A Level Psychology Scientific processes. Each one has a worked solution and a mark scheme showing where the marks go.