The world is a complex place. There are dangers near and far, plant and animal life that seem to love to attack and above all, functions that we need to perform as essential to our survival as individuals. Fortunately, we are helped along in this by our ability to sense and perceive the outside world. This helps us make sense of all the information and understand all the variables and players around us. Sensory abilities aren’t typical to humans alone as all animals and even plant life are able to sense their surroundings to one degree or the other. With every organism, the purpose behind sensation and perception is the same: survival, development and longevity.
So just how do we perceive the world around us? Well in a nutshell, we do it through our different, strategically placed sensory organs (i.e. eyes, nose, tongue, skin and ears). They collect different forms of sensory information or stimuli, transform them into electrochemical signals and send these to the brain for processing. Neuroscientists and cognitive scientists, while identifying the very physical process that change sensations into perceptions, argue that everything we perceive i.e. our whole external reality, is entirely a construct of the brain. This means simply that everything we perceive as our reality happens through the lens of the brain’s interpretation of that stimuli group. This further means that perception is a process of breaking down sensations into “culturally distinct patterns” that fit into an already pre-established schema.
Different parts of the brain handle different perception functions. The temporal lobe handles hearing, the occipital lobe interprets vision (including light, color and visual movement), and the parietal lobe interprets touch sensations, pain, temperature and taste.
How do we label or judge different sensory as adhering to a particular category or typeset? Well that’s where our mental labels come in. We have labels differentiating speech from singing, sounds from music, telling different colors apart, telling horrible odors apart from fragrances and scents, differentiating pain from pleasure, telling apart sweet from salty and so on. Some of these labels come in-built and are there from day one while a host of others we actually have to learn as we grow as infants.
Our brains are constantly bombarded with a bevy of sensory information as we live our everyday lives, a very minute percentage of which it actually has use for. This is where the brain’s in built sensory filter comes into play. It helps the brain sift through the sea of information, identifying and encoding only those that are needed by the individual. This is closely related to sensory adaptation wherein after being exposed to the same stimuli (say, an odor) for a particular period of time, the brain selectively ignores it and focuses on other stimuli.
Sensation and perception are invaluable to our survival as a species and we have our beautiful brains to thank for this marvel. What we perceive acts as information helping us make informed decisions.