Video created by Michael Chin for Mr. Hussey's 12th grade Biology class explains the complexities of the human nervous system with clarity. [9:58]

Observable behavior can be broken down into three psychological categories: innate behavior, learned behavior, and complex behavior. This video offers an in-depth explanation of each category with examples. [12:50]

What happens in the brain when you take a placebo? In this segment, Ira talks with a researcher using brain imaging studies to try to track down the root of the placebo effect.