What do your eyes reveal about you?
« Back to Blog Update
Published: 24 Jan 2013
It has been said that the eyes are windows to the soul. Research has at least shown that the apertures of our eyes offer a glimpse into the mind.
For more than a century scientists have known that our eyes’ pupils respond to more than changes in light. They also betray mental and emotional commotion. In fact, they do this without us knowing exactly why our eyes behave this way.
The visual cortex in the back of the brain assembles the actual images we see. But a different, older part of the nervous system—the autonomic—manages the continuous tuning of pupil. Specifically, it dictates the movement of the iris to regulate the amount of light that enters the eye, similar to a camera. The iris is made of two types of muscle: a ring of sphincter muscles that encircle and constrict the pupil down to a couple of millimetres across to prevent too much light from entering; and a set of dilator muscles laid out like bicycle spokes that can expand the pupil up to eight millimetres.
Stimulation of the autonomic nervous system’s sympathetic branch, known for triggering “fight or flight” responses when the body is under stress, induces pupil dilation. Whereas stimulation of the parasympathetic system, known for “rest and digest” functions, causes constriction. Inhibition of the latter system can therefore also cause dilation. The size of the pupils at any given time reflects the balance of these forces acting simultaneously.
The pupil response to cognitive and emotional events occurs on an even smaller scale than the light reflex, with changes generally less than half a millimetre. By recording subjects’ eyes with infrared cameras and controlling factors that might affect pupil size, such as ambient brightness, colour and distance, scientists can use pupil movements as a proxy for other processes, like mental strain.
Who is Myeyedoc.co.uk?
Alan Hubbard specialises in the treatment of cataracts, ptosis (droopy eyelid), abnormalities of lid position (ectropion/entropion), lid tumours, xanthelasma (minor growths on the eyelids caused by cholesterol under the skin), and lid lumps and bumps. He also performs blepharoplasty – the removal of excessive eyelid skin.
Other relevant interests are his active membership of the British Oculoplastic Surgeons Society www.bopss.org and The Royal College Of Ophthalmologistswww.rcophth.ac.uk. He is a founder member of the Alliance surgical group of surgeons
If you have any concerns or questions, contact us now: click here
© 2024 myeyedoc.co.uk
| all rights reserved |