Processing Speed Peaks at 25, Vocabulary at 65 — Why "Peak Age" Depends Entirely on What You're Measuring
Cognitive processing speed peaks at 18-25, but vocabulary peaks in the late 60s, emotional regulation improves into the 70s, and crystallized intelligence doesn't decline until the 70s-80s. Here's the multiple-peaks framework for human performance, why processing speed loss doesn't translate to overall cognitive decline (strategy, knowledge, metacognition compensate), why marathon runners peak later than sprinters, and the relative age effect that makes September-born UK children more likely to be identified as gifted.