Because her school has decided to support _____, Olivia, a second-grader who has been diagnosed with mental retardation, attends class in her appropriate grade level with her same-aged peers

Internal validity may be increased by

a. matching participants on important characteristics. b. randomly assigning participants to treatment groups. c. employing double-blind procedures. d. all of the above

Recent physiological evidence suggests that

a. changes in the functioning of the nervous system do not reliably accompany early social-emotional interactions. b. changes in the functioning of the nervous system reliably accompany early social-emotional interactions. c. emotional development does not impact the developing brain or central nervous system. d. emotional development impacts the peripheral nervous system more than the central nervous system.