This study guide provides an overview of key topics and definitions from Chapters 1-4 of an Intro to Psychology textbook. Students should be prepared to define scientific method, the different schools of thought in psychology, and the basic functions of neurons and synapses from Chapter 1 and 2. Chapter 3 requires understanding thresholds and types of sensory adaptation. Chapter 4 focuses on altered states of consciousness, sleep stages, and subjective night.