When frustration is repeated: behavioral and emotion responses during extinction over time.

Persistence of instrumental responding and negative facial expressions in response to repeated goal blockage was studied in 53 4-month-old infants. All participants experienced 2 sessions comprising baseline (no stimulation), contingency (stimulation resulting from infant action), and extinction (no stimulation) on consecutive days. Performance criteria identified 2 groups of infants, those who learned in Session 1 (Learning Group 1) and those who learned in Session 2 (Learning Group 2). Individual differences in instrumental responses and facial expression during extinction were compared as a function of learning group. Across sessions, the repetition of extinction for Learning Group 1 was associated with both a persistent instrumental response and anger expressions. The level of instrumental response and anger expression was equivalent to that observed for Learning Group 2 but only in Session 2, the day on which that group learned. Sadness and anger/sadness blended expressions were initially more common in Learning Group 2, but these expressions were attenuated given another exposure to the contingency in Session 2. Implications for the relations among infant emotion, cognition, and behavior are discussed.