Stimulants

In AP Psychology, stimulants are psychoactive drugs (such as caffeine and cocaine) that typically increase neural activity, boosting alertness and energy, and they're covered under Topic 1.3 in Unit 1.

Verified for the 2027 AP Psychology examLast updated June 2026

What are Stimulants?

Stimulants are a class of psychoactive drugs that speed up activity in the brain and body. Per essential knowledge 1.3.C.2.i, stimulants like caffeine and cocaine "typically cause increased neural activity." That increase shows up as more alertness, more energy, and a faster heart rate.

How do they do it? Stimulants mess with neurotransmission (1.3.C.1). Many work as agonists, encouraging neural firing, or as reuptake inhibitors, which block neurotransmitters from getting reabsorbed back into the neuron. Cocaine, for example, blocks the reuptake of dopamine. That means dopamine hangs around in the synapse longer, keeping the receiving neuron stimulated and producing that rush of pleasure and alertness. Different stimulants pull this off in different ways, but the result is the same direction: more firing, not less.

Why Stimulants matter in AP Psychology

Stimulants live in Unit 1: Biological Bases of Behavior, specifically Topic 1.3 (The Neuron and Neural Firing). They directly support learning objective 1.3.C, which asks you to explain how psychoactive drugs affect behavior and mental processes. Stimulants are the clean example of a drug that increases neural activity, which makes them the natural contrast to depressants. If you understand how a stimulant blocks reuptake or acts as an agonist, you understand the whole logic of how drugs hijack normal neural communication.

How Stimulants connect across the course

Depressants (Unit 1)

Stimulants and depressants are mirror images. Stimulants like caffeine and cocaine ramp neural activity up; depressants like alcohol slow it down (1.3.C.2.ii). Knowing one direction makes the other easy to remember.

Reuptake and Neural Transmission (Unit 1)

You can't explain why cocaine works without reuptake. Normal neurons recycle leftover neurotransmitter back into the cell. A reuptake inhibitor blocks that cleanup, so the neurotransmitter keeps stimulating the next neuron longer.

Cocaine and Amphetamines (Unit 1)

These are specific stimulants the CED names. They're the concrete examples that prove the rule that stimulants increase neural activity, often by flooding the synapse with dopamine.

Agonists and Antagonists (Unit 1)

Stimulants often act as agonists, which encourage neural firing (1.3.C.1). Antagonists do the opposite. Sorting a drug into the right category is half the battle on the exam.

Are Stimulants on the AP Psychology exam?

Expect stimulants in multiple-choice questions about neurotransmission and drug effects. A common stem gives you reuptake data (like dopamine reuptake dropping from 500 to 125 molecules/second) and asks you to identify which substance is a stimulant acting as a reuptake inhibitor. Lower reuptake plus reported pleasure and alertness equals a stimulant like cocaine. Other questions ask you to contrast stimulants with depressants (stimulants increase neural activity, alcohol decreases it) or to pick the best lab method for measuring a drug's direct neural effects. No released FRQ has used the word "stimulants" verbatim, but the underlying skill, explaining how a drug alters neurotransmission, is exactly what free-response application questions reward.

Stimulants vs Depressants

Both are psychoactive drugs that change neural activity, but in opposite directions. Stimulants (caffeine, cocaine) increase neural activity and make you feel alert and energized. Depressants (alcohol) decrease neural activity and slow things down. If a question describes more firing, more alertness, or a faster heart rate, it's a stimulant.

Key things to remember about Stimulants

  • Stimulants are psychoactive drugs that typically increase neural activity, with caffeine and cocaine as the CED's go-to examples (1.3.C.2.i).

  • Many stimulants work as reuptake inhibitors or agonists, meaning they keep neurotransmitters firing instead of letting them get reabsorbed.

  • Cocaine blocks dopamine reuptake, so dopamine stays in the synapse longer and produces a rush of pleasure and alertness.

  • Stimulants are the direct opposite of depressants, which decrease neural activity (alcohol is the classic example).

  • On the exam, falling reuptake rates plus reported alertness and pleasure is your signal for a stimulant.

Frequently asked questions about Stimulants

What are stimulants in AP Psychology?

Stimulants are psychoactive drugs that increase neural activity, boosting alertness and energy. The CED names caffeine and cocaine as examples in essential knowledge 1.3.C.2.i, under Topic 1.3 in Unit 1.

Is caffeine really a stimulant?

Yes. Caffeine is one of the two stimulants the CED explicitly names alongside cocaine. Even though it feels mild compared to cocaine, it works in the same direction by increasing neural activity.

How are stimulants different from depressants?

Stimulants increase neural activity and make you feel alert and energized; depressants decrease neural activity and slow you down. Caffeine and cocaine are stimulants, while alcohol is the classic depressant (1.3.C.2.ii).

How does cocaine work as a stimulant?

Cocaine acts as a reuptake inhibitor, blocking the reabsorption of dopamine back into the neuron. Dopamine then stays in the synapse longer, keeping neurons firing and producing pleasure and alertness.

Are stimulants on the AP Psychology exam?

Yes. They appear in multiple-choice questions about neural transmission and psychoactive drugs, often using reuptake data or asking you to contrast stimulants with depressants under learning objective 1.3.C.