Our brains are amazing

SUMMER has arrived and the sun is out. Our scenery rivals the best in world when the sun shines. But to enjoy it you have probably had to wear sunglasses. Sunglasses serve two purposes. They reduce excessive light to a more comfortable level and, more importantly, protect our eyes from UV light which can cause longterm severe damage to our eyes.

Have you noticed whenever you first wear your sunglasses how the world changes colour depending on the tint of the sunglass lenses? Very rapidly your brain adapts to this change and the world is seen in its ‘normal’ colours. Whites appear white and you don’t perceive any colour distortion. This phenomenon is called colour constancy. Another example of the amazing way our brains enhance what we see is stereopsis. Stereopsis is when we see in 3D. Our eyes are placed slightly apart in our heads. Each eye sees at a slightly different angle. When this information is transmitted to our brains, you would think we would see a slight overlap in the two images. In fact we normally only see one image and it is in 3D. Our brains take the images from our two eyes and use the discrepancy in the images to give us depth perception. This enables us to pick that cup of tea without having to move our hands round to find where the cup is actually positioned.

Many of us don’t have stereopsis due to ‘lazy’ eyes or squints. Unless you are blind in one eye or only have one eye, there is the potential to have some depth perception. It’s particularly important that our children have regular eye examinations to ensure they develop 3D vision. Your optometrist will be happy to advise you or refer to a colleague who can help your children.