Unit 2 | Perception
Visual Perception, Gestalt Principles and Visual Illusions
Visual perception
Vision (our sight) is an extremely important way in which we make sense of what
goes on around us. The majority of information about the world around us comes
from what we see. It is our visual perception that helps us to order the patterns and
shapes on this page into letters and words. The way that the eye works is important
in this and you need to know the function of each part of the eye.
Visual perception is about making sense of the information we have gained from our
eyes. We can see how important visual perception is because large areas of the
brain (about half of the cortex) are involved in visual perception. A significant part of
this is the way that the two-dimensional image produced by the retina is changed
into a three-dimensional view of the world. There are two principal aspects to this:
depth perception and size constancy.
Depth perception
This is also called distance perception and is important in everyday life as it helps us
for example, to cross the road. We have to judge that the cars are far enough away
to give us time to cross safely. Depth perception refers to the ways in which we are
able to judge the distance from us of any objects (like cars). We are able to see how
far away objects are using information from both eyes (binocular cues) or one eye
(monocular cues).
Binocular cues – each eye sees an object from a slightly different point. The nearer
an object is to a person, the more the eyes turn inwards (converge) in order to see
the object. The information from the eyes then tells the brain how near or how far
away the object is.
