This post is also available in Dutch.
When I started my master’s thesis project, I was interested in understanding how animals perceive and make sense of sounds. Later, during the writing phase, I started thinking about what shapes our perception of the world and questioning whether there is such thing as “the objective reality”.
What is perception?
Perception is the source of knowledge of our environment; we acquire it from the experience of what surrounds us. Perceiving is about what we learn from our senses in the current context, but also about the memories that a particular scent recalls to us or the emotions that we feel when listening to our favorite song, for example.
My brain, my reality
Reality is not objective at all, as demonstrated by the fact that we all have our own personal mental representations about the same event. We think of our perception of the world as universal ground truth, but it’s not. How fascinating it is to realize that the way the environment shapes our perception, depends on the sensitivity of our sensory system! For example, the human hearing range depends on the anatomical characteristics of the cochlea- the part of the inner ear involved in hearing. Our brains too can shape our reality differently based on our previous experiences. Past traumas, for example, can lead to an altered perception of the real danger in some contexts.
The example of vision: fill the gap
We are visual animals, therefore we mostly rely on our visual system to read a situation. An example of how we build our own representations of the world is illustrated by the phenomenon of fast eye movements (also called saccades). When we make these movements, our vision is temporarily suppressed, and we are functionally blind. Interestingly, we don’t perceive the blind moments, although they are frequent: it has been estimated that this functional blindness occurs during the 10% of our waking hours. The reason is that our brain fills in the missing visual information with the most plausible information for the given situation. The same happens if you accidentally spill some coffee on a text you are reading: even if some of the words have been deleted, you are still able to determine the ones that are missing based on the context.
In the end, it’s a filtered reality!
We live in an environment full of stimuli, and we must narrow down the information we receive in order to carry out the appropriate actions based on unambiguous interpretations. Since we often need to make fast decisions, we must have a clear mental representation of the external world. This is without doubt helpful in numerous daily situations, but it leaves out many nuances. For example, some animals have 12 photoreceptors in their eyes to allow for color vision. Humans, on the other hand, have only 3. The color vision that these animals experience is definitely not the same as ours, and yet we look at the same thing. That’s because there isn’t only one reality; what we experience is always filtered through our senses.
Author: Francesca Abela
Buddy: Kim Beneyton
Editor: Rebecca Calcott
Translation: Floortje Bouwkamp
Editor translation: Felix Klaassen