The Yerkes-Dodson Law states that performance improves as physiological or mental arousal increases, but only up to an optimal point; past that peak, more arousal hurts performance, producing an inverted-U relationship between stress and how well you do on a task.
The Yerkes-Dodson Law describes the relationship between arousal (your level of physiological and mental activation, including stress) and performance. Picture an upside-down U. On the left side, low arousal means low performance, because you're bored or sluggish. As arousal climbs, performance climbs with it, until you hit the sweet spot at the top of the curve. Push past that peak and performance falls. Too much stress makes you choke.
One detail that matters for the AP exam: the optimal arousal level depends on the task. Simple or well-practiced tasks have a higher optimal arousal point, so a little extra adrenaline helps you sprint or do routine drills. Complex or unfamiliar tasks have a lower optimal point, which is why being super amped up before a hard exam or a first performance can wreck you. This is also a known limitation of the law: it doesn't fully explain human performance under stress on its own, because individual differences and task type complicate the neat curve.
The Yerkes-Dodson Law is one of the most cross-cutting concepts in AP Psych. It anchors motivation content (Topics 7.1 and 7.2), where it pairs with arousal theory to explain why people seek an optimal level of stimulation rather than zero stimulation. It shows up again in stress and coping (Topic 7.4, Unit 5: Mental and Physical Health), where it explains why moderate stress (eustress) can sharpen you while overwhelming stress (distress) impairs you. It even connects to the biological bases of memory (Topic 5.6), since stress hormones at moderate levels can strengthen memory while extreme stress disrupts retrieval. If the exam asks you to explain why someone performs better or worse under pressure, this is the concept it wants.
Keep studying AP Psychology Unit 7
Arousal Theory (Topic 7.1)
Arousal theory says we're motivated to maintain an optimal level of arousal, not to eliminate it. The Yerkes-Dodson Law is the performance curve that comes out of that idea. Arousal theory explains why you seek stimulation; Yerkes-Dodson predicts how well you'll perform at each level of it.
Stress and Coping (Topic 7.4, Unit 5)
Yerkes-Dodson is the bridge between 'stress is bad' and 'stress is fuel.' Moderate stress puts you near the peak of the curve and can improve performance, which is the idea behind eustress. Chronic or extreme stress pushes you down the right side of the curve, which is where coping strategies become necessary.
Biological Bases of Memory (Topic 5.6)
Stress doesn't just affect performance in the moment, it affects memory. Moderate arousal can enhance encoding (you remember emotionally charged events well), but high stress during retrieval can block recall. That's the Yerkes-Dodson curve showing up inside your memory system, like blanking on a test you studied for.
Performance Anxiety (Unit 5)
Performance anxiety is what the right side of the inverted U feels like from the inside. When a question describes someone freezing during a recital or bombing an interview they prepped for, it's asking you to recognize over-arousal pushing performance past the optimal point.
This term shows up in application scenarios more than straight definitions. The classic example is the 2018 SAQ about Jackie, who lands the lead role in the school play and feels both nervous and excited. The expected move is to apply the Yerkes-Dodson Law to her situation, explaining that her moderate arousal could boost her performance, while excessive nervousness would hurt it. Multiple-choice questions typically give you a scenario (an athlete, a test-taker, a performer) and ask you to identify the arousal-performance relationship, predict what happens to performance under high stress, or explain how stress affects memory retrieval. Watch for questions about the law's limitations too, since it's tested as an incomplete model that doesn't account for task complexity or individual differences. Your job is always to name the inverted-U pattern, locate the person on the curve, and connect arousal level to predicted performance.
Arousal theory is a theory of motivation. It says we behave in ways that keep arousal at an optimal level, like seeking excitement when bored or calm when overstimulated. The Yerkes-Dodson Law is narrower and more specific. It describes how arousal level affects task performance, and it adds the inverted-U shape plus the twist that optimal arousal is lower for hard tasks and higher for easy ones. If the question is about why someone seeks stimulation, that's arousal theory. If it's about how well someone performs at a given stress level, that's Yerkes-Dodson.
The Yerkes-Dodson Law describes an inverted-U relationship: performance improves with arousal up to an optimal point, then declines as arousal keeps rising.
Optimal arousal depends on the task. Easy or well-practiced tasks peak at higher arousal, while difficult or new tasks peak at lower arousal.
Moderate stress can enhance performance and memory, but extreme stress impairs both, which is why students blank on exams they studied hard for.
On FRQs, apply the law by locating the person on the curve, like explaining that Jackie's pre-show nerves could help her acting up to a point but hurt it past that point.
Know the law's limitation: it doesn't fully explain performance under stress because it ignores individual differences and oversimplifies how task type interacts with arousal.
Yerkes-Dodson connects motivation (arousal theory), stress and coping (eustress vs. distress), and memory (stress hormones and retrieval), so it can appear in multiple units.
It's the principle that performance increases with arousal up to an optimal point, then decreases if arousal keeps climbing. Graphed, it looks like an inverted U, with peak performance at moderate arousal.
No. According to the Yerkes-Dodson Law, moderate stress actually improves performance by raising arousal toward the optimal point. Performance only drops when arousal passes the peak, which happens sooner for complex tasks than for simple ones.
Arousal theory is a motivation theory saying we seek an optimal level of stimulation. The Yerkes-Dodson Law is the specific performance prediction: an inverted-U curve where moderate arousal produces the best performance, with the peak shifting based on task difficulty.
No, and this distinction gets tested. Simple or well-rehearsed tasks benefit from higher arousal, while complex or unfamiliar tasks need lower arousal to perform well. That's why hype helps a sprinter but hurts someone solving a hard math problem.
Extreme arousal pushes you past the optimal point on the curve, and high stress also interferes with memory retrieval. You encoded the material fine while studying at moderate arousal, but test-day panic puts you on the falling side of the inverted U.
Connect this key term to the AP exam workflow: review the course, practice questions, and check related study tools.
Review units, study guides, and course resources.
Check this vocabulary in multiple-choice context.
Apply key concepts in written AP responses.
Estimate the exam score you are working toward.
Review the highest-yield facts before practice.
Put the full course together before test day.