In: Biology
During the first lecture we saw a number of optical illusions. What key aspect of sensory processing did we learn from these examples?
a. That humans have difficulty perceiving parallel lines.
b. That perception is objective: the same visual scene will look identical to all observers.
c. That our perception is heavily influenced by top-down processes.
d. That sensory processing is unambiguous: our senses always precisely represent our environment.
Answer is that our perception is heavily influenced by top-down processes.
In top-down processing, perceptions begin with the most general and move toward the more specific. Such perceptions are heavily influenced by expectations and prior knowledge. If we expect something to appear in a certain way, we are more likely to perceive it according to our expectations
Top-down processing is also known as conceptually-driven processing since your perceptions are influenced by expectations, existing beliefs, and understanding. In some cases, you are aware of these influences, but in other instances, this process occurs without conscious awareness.
A number of things can influence top-down processing, including context and motivation. The circumstances, in which an event or object is perceived can influence what we expect to find in that particular situation. If you are reading an article about food and nutrition, eg.you might interpret a word you're not familiar with as something related to food.