Why study perception
To survive we must know our world. Perception provides knowledge.
Perception is SUBJECTIVE:
Naive realism: Physical versus Perceptual world
Subjective realism: Individual differences. Species differences.
Perception and plasticity: moulding and shaping the brain though experiences e.g. memories.
Perception is a PRODUCT OF BRAIN ACTIVITY
Any physical stimulus is reduced to electrical and chemical elements- materialism.
Brain damage can alter perception e.g. Prosopagnosia ( face blindness).
Phantom limbs-phantom phantom pains.
Artificial limbs were found to be not as effective as first thought. Suprisingly, mirrors were found to be a useful type of therapy.
Perception is BOTTOM-UP and TOP-DOWN:
The Hollow mask Illusion: Rotating mask. When looking at the mask from the back, we can't help but see it as "popping out", facing towards us.
Perception is SELECTIVE:
You don't need to perceive everything
Inattentional Blindness- Attention as a filter. This is very relevant e.g. during + attention.
Approximately 75% of people DO NOT detect the change/ switch of people-getting directions experiment
Tweedle Dum, Tweedle Dee experiment (Simons & Chabris)
Perception is ACTIVE:
e.g. finding food (?), recognising a friend, avoiding abstacles.
Perception is TAILORED FOR OUR WORLD:
Biological motion- Stars looking like a human when they move.
Perception is MULTI-MODAL ( uses info from mant senses):
The McGurk Effect: "Ba, ba" & "Fa, fa"- example of visual processing dominating sound.
Therefore, what we hear may not always be the truth. (also see Naomi's lecture for Language).
The McGurk Effect helps us understand what happens when the senses conflict.
The KEY POINT is that the senses interact therefore showing perception is multi-modal.