AP PSYCHOLOGY

Detailed explanation-1: -At birth the brain is typically 25% of its adult size, although the body weight of the newborn is only about 5% of adult weight (Stuart and Stevenson, 1950).

Detailed explanation-2: -Your baby’s brain grows quickly during their first year of life. To accommodate the growing brain, your baby’s head has to grow, too. During their first year of life, a baby’s head grows 12 centimeters.

Detailed explanation-3: -At birth, a baby’s head is relatively large, making up one-quarter to one-third of his or her total body length, while an adult’s head makes up just one-eighth.

Detailed explanation-4: -Generally, a newborn’s head is about half the baby’s body length in cm plus 10 cm. So a baby that is 18 inches long would be 45.7 centimeters (18 x 2.54). His or her head would be about 32.9 cm or a little under 13 inches.

Detailed explanation-5: -Macrocephaly is the term for an unusually large head. An infant with macrocephaly will have a larger head than most other infants of the same age and sex. In many cases, this condition is benign or harmless. In other cases, it may indicate an underlying medical condition, such as a genetic syndrome or a brain tumor.