When the zygote divides into two cells, the end result is fraternal, or dizygotic twins.
Pregnant women who strapped small speakers to their abdomens during the later weeks of pregnancy had children who were more cognitively advanced at the age of 6 months.
Female fetuses, on average, are more active than males.
With the appropriate training, a one-month-old infant can walk.
Birth complications are related to behavior problems later in life.
Humans experience exerts no influence on motor development.
Habituation to a stimulus indicates that a baby cannot see or remember the stimulus.
The nature of a child's temperament in early life can be a predictor of various behavioral problems that may appear later in life.
In Harlow's experiments infant monkeys developed a strong attachment for a surrogate mother that was actually a wire mesh cylinder with a warmed milk bottle attached to it.
Practically all infants reared in a family develop an attachment to a familiar caregiver by the age of 2.
Separation anxiety in infants who are eighteen months of age is not considered normal.
Children whose fathers exhibit antisocial behavior are more likely to demonstrate such behavior themselves.
The major achievement of the sensorimotor stage is the development of the principle of conservation.
Laura is eight-years-old and just now beginning to understand the concept of reversibility. She is in what Piaget referred to as the concrete operations stage.
Formal operational thought is universal.
The sentence, "Daddy fixded my toy" is an example of telegraphic speech.
Parents are much more likely to correct a child's grammatical error than they are likely to correct the child for saying something untrue.
Individuals who adhere to the nativist position of language acquisition believe that language capability is inherent in human beings.
Children who are raised by authoritative parents have the best prognosis for being successful, well-adjusted adults.
Children of permissive parents are the least self-controlled and self-reliant.
Research indicates physical attractiveness does not play a role in peer acceptance until children are old enough to attend grade school.
According to research, children who are heavy television viewers have the perception that world is a "mean and scary place."