Aim: Students will be able to understand the structure and function of the eye Do Now: Take out your homework to submit (sensation and perception packet), then copy down and answer the following multiple choice question The function of the lens is to Project an image onto the cornea Focus an image on the retina Locate an image Contain receptor cells that are sensitive to light Locate the blind spot Homework: States of Consciousness Homework due on Monday, November 30 (please don’t procrastinate) Exam on Friday, December 4
Vision Our most dominating sense. Aim: Students will be able to understand the structure and function of the eye Vision Our most dominating sense. How vision works Light enters through corneapasses through the pupillens focuses incoming rays into image on retina (accommodation: eyes lens changes shape to focus)rods and conesbipolar cells (sensory neuron with two extensions)ganglion cells (axons form the optic nerve)optic nerve carries information to the brain
Phase One: Gathering Light Aim: Students will be able to understand the structure and function of the eye Short wavelength=high frequency (bluish colors, high-pitched sounds) Long wavelength=low frequency (reddish colors, low-pitched sounds) Great amplitude (bright colors, loud sounds) Small amplitude (dull colors, soft sounds) Phase One: Gathering Light The height of a wave gives us its intensity (brightness). The length of the wave gives us its hue (color). ROY G BIV
Retina’s Reaction to Light- Receptors Aim: Students will be able to understand the structure and function of the eye Retina’s Reaction to Light- Receptors Rods detect black, white and gray Cones near center of retina fine detail and color vision daylight or well-lit conditions
Vision- Receptors Receptors in the Human Eye Cones Rods Number Aim: Students will be able to understand the structure and function of the eye Vision- Receptors Receptors in the Human Eye Cones Rods Number Location in retina Sensitivity in dim light Color sensitive? Yes Low Center 6 million No High Periphery 120 million
Normal Nearsighted Farsighted Vision Vision Vision Aim: Students will be able to understand the structure and function of the eye Acuity- the sharpness of vision (can be affected by distortions in the eye’s shape) Nearsightedness- condition in which nearby objects are seen more clearly than distant objects Farsightedness- condition in which faraway objects are seen more clearly than near objects Normal Nearsighted Farsighted Vision Vision Vision
Visual Information Processing Feature Detectors Located in the visual cortex nerve cells in the brain that respond to specific features shape angle movement We have specific cells that see the lines, motion, curves and other features of this turkey. These cells are called feature detectors.
Visual Information Processing Aim: Students will be able to understand the structure and function of the eye Visual Information Processing Parallel Processing processing of several aspects of a object simultaneously
Distribution of rods and cones This demonstrate provides an illustration of the distribution of rods and cones in the retina, as well as of the differing ability of these photoreceptors to detect color. More specifically, it demonstrates that stimuli in the center of the visual field are detected by color sensitive cones concentrated in the fovea, while stimuli on the edges of the visual field are detected in the periphery of the retina by rods, which are not sensitive to color
Process Student will sit at the front of the room facing the class, and focus their eyes ONLY on a spot or object at the back of the room If the subject’s eyes stray away from the fixation point, the demonstration will probably not work very well With the subject’s eyes fixated, stand directly to the subject’s left and hold a colored marker/pen about four feet away from their left ear, at about their eye level (Do not allow the subject to see ahead of time what you are holding)
Tell the subject you are holding something in your hand and ask them what it is and what color it is Then move forward a foot or so and ask the same question Continue to ask these questions each time you move, one foot at a time, in an arc that would eventually place the object in front of the subject