When you taste pizza you are having a percept, a product of perception. Perception is the mental process that interprets and gives meaning to sensations. Color serves as an example as to how perception differs from person to person. A color may not be the same for everybody, such as red. The color "Red" to an individual might be different to another individual, but we learn at an early age that the specific color is known as "Red". Other examples include illusions and ambiguous figures. Biologically, we have these things called Feature Detectors, which are the cells in the Cerebral Cortex that specialize in taking certain features of a stimulus. The brain combines sensory details into a single percept and this unclear process is referred to as the Binding Problem. Although the binding problem has not been solved, scientists believe that it can be partially accounted for by the brain's control of the firing patterns of neurons that recognize specific elements. Bottom-Up Processing emphasizes characteristics of stimuli, rather than our concepts in their entirety and expectations. Top-Down Processing is the process of perceiving things based off of your concepts, expectations, memories, motivations, goals and information gathered over time. Perceptual Constancy is the ability to recognize the same object as remaining "constant" under different conditions.
Gestalt Psychology argues that perception is shaped by nature, or innate factors that were already built into the brain. It divides our perception into Figure and Ground. Figure is the main part of the stimuli that catches our attention immediately, and ground is the backdrop against which we perceive the figure. Our perception can also be divided into Monocular cues, cues taken from just one eye, and Binocular cues, which rely on the use of both the eyes. Closure (filling in the blanks) is an organizing process identified by Gestalt psychologists. Gestalt psychologists also recognize laws of perceptual grouping, such as the Law of Similarity, Law of Proximity, Law of Continuity, Law of Common Fate, and Law of Pragnanz. These laws are theorized to be automatically built into our brain.
Another explanation for perception was made by Hermann von Helmholtz, who recognized the role of learning, or nurture in Perception. His theory of Learning-Based Inference states that perception is mostly shaped by personal experience and inferences made through prior learning. Context, expectations, and Perceptual Set also effect Perception. The Proprioceptive Senses are Kinesthesis, Visceral Sensitivity, Vestibular Sense. The Vestibular sense is when you sense that something is moving around you, and you use your coordinated movement to stop it from moving. An example of this would be when your pencil falls off your desk, and you sense it doing so, so you catch it before it reaches the ground.
Gestalt Psychology and Helmholtz's Learning-Based Inference are not opposing viewpoints in the sense that both are needed to understand our everyday perceptions. Also, both theories require top-down processing and rely on the attention of the subject in order to meaningfully perceive a stimulus. Also, Gestalt psychologists believe that much of perception is shaped by innate factors that are built in the brain.
Although the concept of change blindness wasn't in the book, it's important to know that it's the inability to see changes in an environment. If you aren't paying attention, then you won't notice changes.