In late adulthood, the amount of time spent in Stage 1, the lightest sleep, ____, and time in the deepest sleep of Stage 4 and REM sleep ____

A core change unique to formal operations is that teens can:

a) conserve much better. b) reason abstractly about hypothetical possibilities. c) read at a much higher level. d) really take another person's point of view

Protowords

a. result when a child's caregivers use and encourage "baby talk." b. are preverbal attempts of young children to communicate with each other. c. are unique strings of phonemes invented by the child. d. support the hypothesis that children's speech is insensitive to context. e. are taught to children by their older siblings.