Visual Perception Flashcards
(42 cards)
Pupil
A hole which takes in light so the eye can focus in front of it
Cornea
The outer covering of the eye which protects the eye from elements which could damage the inner parts. Helps to focus light more effectively
Iris
Contains pigment. Dilator pupilate muscles help Widen and shrink pupil. Allows either more or less light to enter.
Lens
Clear layer which focuses the light that the pupil takes in. It is held in place by the ciliary muscles, which allows it to change shape depending on the amount of light
Ciliary muscle
Controls the shape and movement of the lens
Aqueous humour
Watery substance which fills the eye. Allows the eye to maintain shape
Retina
Made of rods and cones which transmits light into chemicals and electrical pulses which is sent to optic nerve to interpret
Vitreous humour
Helps hold shape of eye. When debris is found it creates floaters so it is not in clear Vision
Optic nerve
Carries nerve impulses to occipital lobe of centrum where vision is located.
Fovea
Responsible for central and sharpest point of vision.
Blood vessels
Nourish the retina
Blind spot
Small area of retina which is insensitive to vision.
Sensation
The physical stimulus, together with physical properties is registered by sensory organs, which decode information and turn it into neural impulses or signals. Eg seeing touch and smell
Perception
Follows after sensation through a series of organisation, transition and interpretation. Meaning a person is able to ‘make sense’ of the sensation.
Visual illusion
Occurs when perception consistently differs from objective reality. It is caused by a psychological factor and not a biological factor.
Synathesia
The crossing of senses where the occurrence of a stimulus from one sensory automatically triggers a perception in the second sensory.
Ponzu illusion
When you mistakenly perceive the length of an upper horizontal line due to depth cues of linear perspective and height in visual field. Projects image onto retina where you perceive the most distant to be longer.
Muller lyer - arrows
Two lines of equal length, each having opposite shaped arrows, inverted and normal shaped arrows. The line with death tail is perceived longer
Ames room
Made to appear square through a peephole which prevents bio ocular depth cues. The rear wall runs right - left from the observer. The ceiling is also not parallel to the floor as it slopes downwards. Therefore height is developed in far left corner. While the right corner maintains shape constancy but not size constancy.
Electromagnetic spectrum, when is visible light
The energy that enables us to see is light energy as displayed on the spectrum. We can see visible light from 360-760
Absolute threshold
The minimum amount of physical energy needed for an observer to perceive a visual stimulus in ideal conditions 50% to the time.
Perceptual set
A predisposition to attend to certain aspects of the visual scene, or to interpret stimuli in a particular way. Interpreting what we see in context to preconceptions including previous experience motivation and emotion .
Rat man experiment
When shown animals - rat
When shown human - man
Rods
Photoreceptors which provide peripheral vision in black and white. And work in dim light.
