| rdfs:comment | - Peripheral vision is the range of visual perception that lies outside the central stereoscopic vision of the eyes. In a person with normal sight, visual stimuli can be perceived outside the central focus of vision in a field of over 200 degrees from side to side and over 130 degrees from top to bottom even if an object in this area cannot be directly identified by either shape, color or detail . Rapid movement in this field usually results in a reflex of turning the head in the direction of movement to aid in perception and, if the movement is headed towards the eyes, the blink reflex.
- Have you ever gotten a glimpse of something out of the corner of your eye? A simple movement caught in your peripheral vision. Most will simply dismiss this as a shadow brought about by a flickering candle, or perhaps a pet jumping down from a piece of furniture. But then there's that one elusive sight. It can easily be explained by the above conditions, but something feels wrong about it. A chill down your spine, a slight pain in your side. Maybe even a complete blanking of your mind, only to recede moments later.
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| abstract | - Have you ever gotten a glimpse of something out of the corner of your eye? A simple movement caught in your peripheral vision. Most will simply dismiss this as a shadow brought about by a flickering candle, or perhaps a pet jumping down from a piece of furniture. But then there's that one elusive sight. It can easily be explained by the above conditions, but something feels wrong about it. A chill down your spine, a slight pain in your side. Maybe even a complete blanking of your mind, only to recede moments later. Should any of these symptoms be felt, there may be cause for worry. Our peripheral vision is designed to catch motion, even in the dark. This was used to defend against predators in our early days, and as with many aspects of our human nature, it has remained, but weakened. This view out of the corner of our eyes still alerts us to danger, and although predators have dropped on the list of dangers we may face today, they still exist. Should you ever feel that queer chill in your back, try not to focus on that shadow you saw in the corner of your eye. It might be better not to see.
- Peripheral vision is the range of visual perception that lies outside the central stereoscopic vision of the eyes. In a person with normal sight, visual stimuli can be perceived outside the central focus of vision in a field of over 200 degrees from side to side and over 130 degrees from top to bottom even if an object in this area cannot be directly identified by either shape, color or detail . Rapid movement in this field usually results in a reflex of turning the head in the direction of movement to aid in perception and, if the movement is headed towards the eyes, the blink reflex. The structure of the retina concentrates the cells that perceive detail and color in the central portion (the fovea) while cells that are more sensitive to changes in light levels and movement are concentrated towards the outer range. Several conditions can affect peripheral vision, either permanently (such as mascular degeneration) or temporarily (alcohol or fatigue). Peripheral vision can be measured either automatically or manually. In both cases, the patient is asked to stare straight ahead and a visual stimulus is moved into the peripheral field. Automatic machines can accurately record the position which results in a stimulus. .
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