Perception is how we identify and comprehend people places and things in the world around us. When it comes to perception in psychology there are two main concepts that need to be acknowledged those of bottom-up processing and top-down processing. The combination of these two concepts is how we view or perceive the world that we live in.

Bottom-up processing is sensory driven and involves the ways in which our eyes, ears, nose, skin, and tongue take cues from the environment and convert them into thoughts and responses in our brain. For example, if a person hears a loud noise a signal, known as an action potential, is sent from the ears to the brain to alert the person that there is a loud noise. The conversion of environmental senses to brain activity is referred to as transduction. What we do with that information is top-down processing.

Top-down processing involves an examination of our surroundings and based on previous knowledge, as well as experience, determine what that means to us as individual. We have developed conclusions about the aspects and characteristics of components and attributes associated with the world around us and use these conclusions to determine how we perceive things. For example, if we run across an individual who is crying outside of a hospital, we presume that that individual is hurt or in distress, that would be a big picture analysis based on prior experience and knowledge. Top-down processing allows us to make a quick assessment of the environment based on what has happened in the past.

To examine the combination of these two processes I would like to pose the example of a blind date from my male perspective. As I approach my date from a distance, my top-down processing begins, and my first impressions begin to take shape. I notice that she is dressed well, nothing too flashy or over the top, with a nice touch of fashionable accessories to compliment her clean cut out fit. My top-down processing tells me that she is confident, responsible, and organized. As I continue to approach her my bottom-up processing surges as she acknowledges my presence with an outreaching hand and smile inquisitive yet inviting smile. More bottom-up processing occurs and action potentials fire as we make eye contact and I notice that the subtle aroma of her perfume. As our conversation continues so continues the processing. Her voice (bottom-up processing) is assertive but not loud, confidant but not aggressive (top-down processing). The combination of the two processes has led me to the perception that this is the kind of person I like and that this is going to be a good date.

We use perception to guide our lives every day and perception differs between individuals based on the combination of bottom-up and top-down processing. Some people view a glass of water as being half full and others as half empty. My blind date is but one example of an encounter involving perception. Was she a nice girl? In my perception the answer is yes. We are continually bombarded with bottom-up stimuli. We take sensory cues from the environment (bottom-up processing) and based on our top-down processing have learned to convert them into perceptions based on our knowledge and experiences. The Bottom-up processing is the sensory input, and the top-down processing is how we interpret the input. The interplay between the two processes forms our perception.

References

Goldstein, E. B. (2011). Cognitive psychology: Connecting mind, research and everyday experience (4th ed.). Wadsworth, Inc.