How does your brain create a picture?When you look at a scene, each of the different 'seeing' areas in your brain seems to have a 'map' of the scene to which it adds details - like movement, colour, depth or shape. Scientists have learnt a lot about how you see by studying patients who have damage to these areas. Damage to any area can mean that the final picture is missing a particular detail.
What is it?
Many of the neurons in the visual part of the brain respond specifically to edges orientated in a certain direction. From this, the brain builds up the shape of an object. Information about the features on the surface of an object, like colour and shading, provide further clues about its identity. Objects are probably recognised mostly by their edges, and faces by their surface features.
Where is it?
Is it moving?
What is agnosia?
How do you recognise faces?
When you try to recognise an unfamiliar face, you look for several things such as gender, age and race. People are very good at deciding whether a face is male or female, even when obvious clues – such as make-up and hairstyle – are missing. This judgement relies on many features, including thickness of eyebrows and how much the nose sticks out, both of which are more pronounced in men.