This program deals with electroencephalography, recording impulses from the brain. Dr. Walker explains the parts of the brain and a diagram of nerve cells discharging impulses. Lights on a model of a human head indicate brain activity under differing conditions. Dr. Marshall demonstrates how eighteen electrodes are attached to the scalp to record brain waves during an EEG (electroencephalogram) and notes that this is simply a diagnostic tool. He explains the EEG machine and shows the graph produced by the output of its amplifiers. Dr. Marshall then explains what constitutes a normal brain wave based on comparing the voltage and rhythm of a large sampling of medically normal people. Dr. Walker compares several EEG records with differing patterns, and Dr. Marshall explains the significance of the differences, including one lengthy EEG from a patient having an epileptic seizure.

Convulsive seizures or epileptic fits can be caused by problems in the heart, pancreas, kidney, or febrile conditions, but by far the most common causes are problems in the brain, although many have unknown causes. Some epileptics can be assisted through surgery, while others can be helped my medications such as phenobarbital, dilantin, or tridione. Epilepsy can be reproduced in monkeys to help study the disease and develop further methods of treatment.

Neurological surgeon Walker explains that the brain is composed of neurons, nerve cells that convey impulses to various parts of the body and store memory of impulses. He shows a diagram of the dendrites and axons of the neurons and explains a cross-section model of a neuron. Lynn Poole lists some of the history of the research on brain functions, including that of the early German phrenologist Franz Joseph Gall. In 1817 it was demonstrated that electrical stimulus applied to the brain produced movement on the opposite side of the brain, giving rise to the existence of motor areas of the brain. Using a brain cross-section diagram related to various parts of the body, Dr. Walker shows how the sensory cortex, or homunculus, is closely correlated with the motor cortex. He also discusses what happens when these areas are injured and how they affect vision, hearing, and speech. The association area of the brain is the temporal lobe. Personality and drive may be located in the frontal lobe as lobotomies in that area produce personality change and induce apathy. Additional research is needed to discover if patterns of pathways between nerve cells are responsible for psychological differences.