Final answer:
As the caffeine dose increases, cognitive performance tends to increase continuously. Caffeine interacts with adenosine receptors in the brain, blocking the actions of adenosine and increasing energy metabolism, leading to increased alertness and delay of fatigue and sleep.
Step-by-step explanation:
According to research, cognitive performance can be affected by the dose of caffeine consumed. As the caffeine dose increases, cognitive performance tends to increase continuously. Caffeine interacts with adenosine receptors in the brain, blocking the actions of adenosine and increasing energy metabolism, leading to increased alertness and delay of fatigue and sleep. However, it's important to note that individual arousal levels can also impact cognitive performance, so the effects of caffeine may vary from one person to another.