(4) Vision, Sensation, and Perception Flashcards
What is sensation?
The process by which we receive, transform, and process stimuli
What is the difference between sensation and perception?
Sensation: take in info from stimuli in our environment;
Perception: interpret and organize sensations mentally
What is an absolute threshold?
The smallest amount of a stimulus that someone can reliably detect
What is a difference threshold?
The minimal difference between two stimuli that a person can reliably detect
What is sensory adaptation?
Sensory systems become less sensitive to constant/unchanging stimuli
What is visual accommodation?
The lens changes shape to adjust for the distance of an object, which helps to focus the visual image (on the retina–inner surface of the eye)
What is the function of the iris?
Change shape to dilate/constrict the pupil
What is the function of the lens?
Change shape to adjust for an object’s distance
What is the function of the rods?
Low-light, night, and peripheral vision
What is the function of the cones?
Enable color and central vision in higher light conditions
What are the two main categories of photoreceptors?
Rods and cones
What is the eye’s blind spot?
The place in the back of the retina where the optic nerve connects, so there are no photoreceptors to provide vision
What is the function of feature detectors?
Neurons that respond to specific visual characteristics like lines
What is the trichromatic theory?
the ability to see different colors depends on the relative activity of three types of color receptors in the eye: red, green, and blue-violet
What is the accepted explanation for color vision today?
Most authorities today state that color vision incorporates evidence of aspects of both trichromatic color vision theory and opponent-process theory
