This diagram demonstrates Gestalt's Law of Closure. The human brain tends to perceive complete shapes even if those forms are incomplete.
Perception is defined as “a rapid, automatic, unconscious process by which we recognize what is represented by the information provided by our sense organs”1. Perception is not deliberate or effortful. We do not first see an object and then perceive it; we simply perceive the object.
The primary function of the sense organs is to provide information to guide behaviour. Sensory mechanisms cannot do this on their own. Without association cortices to accompany our primary sensory cortices, we would have no understanding of the world around us.
Because of the importance we give to vision and the vastness of information provided by our visual system, auditory perception is a great guiding framework. "The brain receives fragments of information from approximately 1 million axons in each of the optic nerves. It combines and organizes these small fragments into a perception of the scene.'1 This perception includes objects having different forms, colors, and textures in different locations in a three dimensional space.
Visual perception by the brain is understood by many as a hierarchy of information processing. According to this, “neural circuits analyze particular aspects of visual information and forwards these results to another circuit that performs further analysis."1 The higher levels of this process interact with memories, recognizing familiar objects and learning unfamiliar ones.
The primary visual cortex is necessary for visual processing, although the perception of the totality of the scene does not occur there. The combination of information from the different modules from the primary cortex happens at several levels of the visual association cortex.1
Perception involves both bottom-up and top-down processing. “Our perceptions are influenced not only by the details of the particular stimuli we see, but also by their relations to each other and our expectations."1
There are countless tricks our minds play in the process of a total perception. These include perceptual constancy, Gestalt’s laws of grouping, and contrast effects. Learn about these and more in the Perception section of BrainMass.