Perception (from the Latin perceptio) is the organization, identification, and interpretation of sensory information in order to represent and understand the environment. All perception involves signals that go through the nervous system, which in turn result from physical or chemical stimulation of the sense organs. For example, vision involves light striking the retina of the eye and smell is mediated by odor molecules reaching the olfactory receptors. Perception is not only a passive process, but is also shaped by memory and learning.
Most research on perception has focused on visual perception, because it is easier to study than other types of perceptual systems (e.g., auditory or tactile). Furthermore, vision provides an excellent example of how different levels of processing are involved in perception. At its simplest level, we can say that light enters the eye and receptor cells are stimulated. This stimulation then leads to electrical impulses that travel along neurons to various areas in the brain where they are further processed. However, this simple model does not take into account all that happens during visual perception – for instance, how we recognize objects or interpret scenes as three-dimensional despite being able to see them only two-dimensionally on our retinae. To understand these processes requires knowledge about many aspects of physiology (e.g., how photoreceptor cells work), neuroscience (e.g., properties of neurons), psychology (e.g., principles governing object recognition), and computer science (e.g., algorithms for extracting 3D shape from 2D images).
The first step in perceiving something is for energy from our surroundings – whether it belight waves or sound waves -to hit our sense organs: eyes for vision; ears for hearing; nose for smell; tongue for taste; skin for touch/pressure; and proprioceptors located throughout our bodiesfor movement/balance information.. These receptors send information via nerve pathways to specific regions in our brains where further processing occurs.. The natureof this processing depends on what we want to perceiveand can range from very simple computations – such as detecting an edge– to more complex ones such as recognizing a faceor making a decision..