Behavior is learned and has consequences

Cognitive development refers to lifelong changes in our

a) personalities. b) moral reasoning. c) thought processes. d) social interactions.

A major limitation of cross-sectional research is that

A) age-related changes may be distorted because of participant dropout. B) findings may not generalize to the real world. C) age differences may be distorted because of cohort effects. D) control over the treatment group is usually weak.