Perception is a topic within cognitive psychology I just found to be fascinating. It is defined as the process whereby we recognise, organise and make sense of sensations we receive from environmental stimuli. As said by Frith in 2007, “My perception is not of the world, but of my brains model of the world”.
It may not seem very apparent now, but after reading this blog you will realise how much actually goes into the way humans can perceive different things. To begin, there are a combination of two different processes in which together help us perceive things. There is ‘bottom-up processing’, where our brain reacts to pieces of information from the outside world. For instance, if a picture of a bird was presented in front of you your brain would start to identify the different features that it knows make up a bird, e.g. feathers, beak, claws etc. The second process is known as top-down processing, in which is previous knowledge of what to expect. A famous example of top-down processing is known as the Charlie Chaplin hollow face illusion, whereby a mask of Charlie Chaplin appears to be hollow but is in fact a solid figurine of the mans face.
More interestingly with perception is the deficits that accompany it. Visual agnosia is a group of neuropsychological disorders characterised by a failure to recognise familiar objects. This comes in many forms; visual (apperceptive), an inability to assign meaning to a stimulus (associative) and probably the scariest, the inability to recognise faces, known as prosopagnosia. This is theorised to happen when one stream of visual processing does not work. The ventral stream is for perception and recognition of objects. The dorsal stream is vision for action, it mediates visual control of skilled actions directed at objects in the world (Milner and Goodale, 2008).
Overall, the field of perception within psychology is vastly interesting and very extensive in its research, making it a fascinating sub section to study.