There are many examples of bottom-up processes that we experience daily. This sensation or environmental energy is then converted into action potential, which this process is called transduction (Mack). The bottom-up process starts when we experience sensation through the receptors in our eyes, skin, tongue, nose, and ears (Mack). The names of the processes make it easy for us to remember how the processes are.

From the definition of these two processes, you can see the differences in the flow of the process. The top-down process occurs when we generate perception through our past experiences, knowledge, and expectations. We gain this information or energy from receptors in the sensory organs. The process where information is gained from our senses as environmental energy and converted into action potential and sent to the brain is called the bottom-up process. The fact that you no longer perceive the sound demonstrates sensory adaptation and shows that while closely associated, sensation and perception are different.In this week’s lesson, we learn about perception which is defined as the recognition, organization, and interpretation of information from our sensory experiences. The clock is still ticking, and that information is still affecting sensory receptors of the auditory system. Upon first entering the room, you can hear the ticking of the clock as you begin to engage in conversation with classmates or listen to your professor greet the class, you are no longer aware of the ticking. Imagine entering a classroom with an old analog clock. In fact, we often don’t perceive stimuli that remain relatively constant over prolonged periods of time. For example, upon walking into a kitchen and smelling the scent of baking cinnamon rolls, the sensation is the scent receptors detecting the odor of cinnamon, but the perception may be “Mmm, this smells like the bread Grandma used to bake when the family gathered for holidays.”Īlthough our perceptions are built from sensations, not all sensations result in perception. One way to think of this concept is that sensation is a physical process, whereas perception is psychological. Now you are processing the shape in a top-down fashion. When given a context, your perception is driven by your cognitive expectations. Surrounded by numbers, the same shape now looks like the number “13.” Figure 18. In that context, you perceive the lines to form the shape of the letter “B.” Figure 17. Surrounded by sequential letters, your brain expects the shape to be a letter and to complete the sequence. Now, look at the same shape in two different contexts. There is no context to give it a specific meaning, so there is no top-down processing involved. There are two thick vertical lines and three thin horizontal lines. Seen alone, your brain engages in bottom-up processing. On the other hand, how we interpret those sensations is influenced by our available knowledge, our experiences, and our thoughts. Bottom-up processing refers to the fact that perceptions are built from sensory input. Perception involves both bottom-up and top-down processing. Perception refers to the way sensory information is organized, interpreted, and consciously experienced. While our sensory receptors are constantly collecting information from the environment, it is ultimately how we interpret that information that affects how we interact with the world.

Bottom up vs top down psychology