The Human Brain

This online book accompanies the course. It is organized into units. Each unit begins with a substantial overview chapter, followed by more focused chapters.

This textbook is currently under construction and will officially open for the Fall 2026 semester.

Begin with Unit I →

Contents

Unit I — The Embodied Brain

• The Brain as a Control System
• Why Have a Brain?
• Evo-Devo and the Vertebrate Brain Plan
• The Embodied Brain
• The Brain as a Connected Map

Unit II — The Hypothalamus and the Regulated Body

• Overview: The Hypothalamus and the Regulated Body
• Thermoregulation
• Fluid Balance and Thirst
• Energy Balance and Hunger
• Sleep and Circadian Rhythms
• Stress and the HPA Axis
• Aggression and Defense
• Reproduction
• Social and Parenting Behavior
• Exploration

Unit III — Signaling

• Overview: Signaling
• The Cells of the Brain
• How a Neuron Is Excited
• The Slow Chemistry
• How a Synapse Learns

Unit IV — Sensing the World for Action

• Overview: Sensing the World for Action
• Somatosensation: The Body Senses
• Pain: The Sense That Tells You Something Is Wrong
• Audition
• The Visual System I: Turning Light Into Difference
• The Visual System II: Building a World in the Cortex
• The Visual System III: When Seeing Breaks
• Taste: The Sense That Decides Whether to Swallow
• Olfaction: The Sense That Breaks the Plan

Unit V — Action

• Overview: Movement — The Control System in Action
• Getting to the Muscle
• Acting on the Seen World
• The Predicting Machine
• Choosing What to Do
• What It’s Worth

Unit VI — Goal-Directed Futures

• Overview: The Organ of Tomorrow
• A Common Currency
• Holding the Line
• Feeling the Future
• The Futures of Others
• Wandering When Full
• Tomorrow Never Comes

Unit VII — Predictive Maps

• Overview: The Predictive Map
• The Oldest Map
• Drawing the Map
• Navigating Things That Are Not Places
• The Diary on the Map

Unit VIII — The Social Niche

• Overview: A Murder of Brains
• Words Between Brains
• The Nearest Agent

Appendices

• Genetics Primer
• Methods Primer