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Parallel processing refers to the ability of our brain to simultaneously process multiple pieces of information or stimuli at the same time, rather than one at a time. It allows us to efficiently analyze and interpret complex visual scenes.
Sensation is the process by which our sensory receptors detect and respond to external stimuli.
Perception is the process of organizing and interpreting sensory information in order to give it meaning.
Bottom-up processing involves analyzing individual elements of a stimulus separately before integrating them into a whole perception.