AP Psychology › Unit 3
This unit follows change across the lifespan and the ways we learn. You will study physical, cognitive, and social development, including Piaget's stages, language, and attachment, then classical conditioning, operant conditioning, and observational learning. Exam questions often describe a study and ask about longitudinal versus cross-sectional design or what a statistic means. The most common error is confusing classical and operant conditioning. Classical pairs two stimuli; operant links a behavior to its consequence. Students also think negative reinforcement means punishment, when it strengthens behavior by removing something unpleasant.
These are taken from the Regular set, with the answer and explanation shown.
1. At a 12-month checkup, a pediatrician watches whether an infant can pick up a single small cereal piece between her thumb and forefinger. The pediatrician is checking
Answer: C. Picking up a tiny object with thumb and forefinger is the pincer grasp, a fine motor skill. Fine motor skills use small muscles of the hands and fingers. They emerge as the nervous system and muscles mature.
Common trap: Choosing an inborn reflex. Reflexes such as rooting are automatic responses present at birth. A deliberate pinch to pick up food is a voluntary motor skill that emerges with maturation.
Researchers observed 100 twelve-month-old infants with their primary caregivers in the Strange Situation, a playroom procedure in which the caregiver leaves twice and returns, and a stranger enters. Two trained observers, who knew nothing else about the families, classified each infant's attachment from video recordings. The table shows the results.
| Attachment classification | Number of infants (out of 100) |
|---|---|
| Secure | 62 |
| Insecure-avoidant | 18 |
| Insecure-anxious | 12 |
| Disorganized | 8 |
Hypothetical study and data written by Practice Dojo for practice. Not a published study.
2. What percentage of the infants were classified as insecurely attached?
Answer: B. The insecure categories are avoidant (18), anxious (12), and disorganized (8). Together, 18 + 12 + 8 = 38 of 100 infants, or 38 percent. The other 62 percent were secure.
Common trap: Leaving out the disorganized group and answering 30 percent. Disorganized attachment is also an insecure type, so its 8 infants count.
3. Ms. Ortiz gives surprise quizzes at unpredictable times, sometimes twice in one week and sometimes not for two weeks. Students who review their notes a little every day do best. Reviewing is being reinforced on which schedule?
Answer: A. The payoff for reviewing, doing well on a quiz, depends on time passing, and the timing is unpredictable. That is a variable-interval schedule. It produces slow, steady responding, which is why daily review works.
Common trap: Choosing variable-ratio because the quizzes are unpredictable. Ratio schedules depend on the number of responses. Reviewing more times does not make a quiz come sooner.