Caffeine and Its Effects on the Brain

What type of substance is caffeine?

• A stimulant drug

• A methylxanthine

• A mind-altering substance

• All of the above

How does caffeine primarily affect the brain?

• It increases the production of adenosine.

• It blocks adenosine receptors.

• It promotes the release of GABA.

• It directly activates neurons involved in wakefulness.

What is the typical effect of adenosine on the brain's activity related to sleep?

• It promotes wakefulness by increasing dopamine.

• It inhibits neurons involved in wakefulness, leading to sleep.

• It directly stimulates arousal pathways.

• It has no significant effect on sleep regulation.

How does caffeine contribute to increased arousal and wakefulness?

• It enhances the sleep-promoting effects of adenosine.

• It directly increases the release of GABA.

• It opposes the action of adenosine, which normally promotes sleep.

• It reduces the activity of stimulating neurotransmitters like dopamine.