​The primary pioneer in the study of behaviorism was Erik Erikson.

Through the first 12 months of life, infants have a very general prototype for a face that is fine tuned to be more consistent with familiar faces between 12 and 24 months of age.

​An embryo rests in a sac called the placenta, which is filled with amniotic fluid that cushions the embryo and maintains a constant temperature.

​The reliability of a research measure refers to the extent to which that measure provides consistent evaluations of a given characteristic.

At around 18 months of age, children will learn approximately 10 or more new words and labels each week.

By the age of 24 months, most children can climb steps, walk backward, and kick a ball.

​Changes in heart rate or brain-wave activity that occur in response to the introduction of a new stimulus are called a(n) ____ response.

​Complex emotions differ from basic emotions in that complex emotions require some understanding of

​If a dominant gene meets up with a recessive gene, the traits that are contained in the dominant gene will ultimately be expressed.

​Phonemes refer only to vowel sounds and morphemes refer only to consonant sounds.