In Chapter 4, the book defines sensation and perception and how our five senses (sight, hearing, smell, taste, and touch) help us to perceive and understand our world. The chapter demonstrates how the visual and auditory system work in addition to our sensual and body senses.
While glancing through this chapter, I found the visual system was quite interesting. The book explains blindness, or the inability to see, and how our brain demonstrates brain plasticity. Because the blind cannot rely on their sense of sight, we believe their other senses become stronger. However, in brain plasticity, brain regions that aren't used slowly take over functions of other parts of the brain. For example, the somatosensory and visual cortex can be devoted to sensing touch, resulting in being more sensitive to touch, allowing them to read Braille.
I also learned about motion blindness, which is when one can't process still images together as an ongoing motion. The book gives an example which I can relate to: One second a car may seem to be 100 feet away while crossing the street, but the next second the car may be one foot away. Some still images in between are lost because of motion blindness.
Chapter four goes in-depth with the other senses also, so it will be interesting to learn how all of our senses work together to form perceptions of the world we are in.