The gaps in the myelin sheaths on axons are known as:

A child is playing with plastic models of cows and horses on a toy farm. She takes some of the animals out of the field and places them in the barn exclaiming, "Oh my! Now the field is much bigger."

The child's perception is characteristic of the ______ stage. a. sensory-motor c. concrete operational b. preoperational d. formal operational

Echoic memory has an estimated duration of:

A) up to 30 min. B) up to 8 sec. C) up to 4 sec. D) up to 1 sec. E) up to 30 sec.