Answer:
Holding the head up. Infancy is a period when the baby grows very fast. During infancy, the baby doubles in length and triples in weight. Other important changes also happen during infancy: ... The baby starts smiling, paying attention to other people, and grabbing toys.
The technique being used is Positron Emission Tomography. The PET scanner will measure the amount of positrons that collide with the electrons in the brain, and this data will then be analyzed using a computer program that generates a color map of activity in the brain. These colors range from purple (little to no activity) to red (high or very high activity).
