1. Multiple Choice Yes/No and True/False and Matching Study the lecture notes, textbook My office hours are after class (NOTE: I won’t talk about the test material once students have started taking the test!) Midterm Thursday and Friday

2. What kind of energy does the visual system sense and perceive? The Visual System

3. Light is an oscillation (a wave) in the electromagnetic field Light

4. What are some characteristics of light waves? Properties of light

5. What are some characteristics of light waves? –amplitude/intensity - how big of a fluctuation in the field/how many waves –frequency - how many fluctuations (waves) pass by a certain point in a given period of time –polarization - the orientation of the waves Properties of light

6. What perceptions are associated with those physical properties? Properties of light

7. What perceptions are associated with those physical properties? –Intensity is associated (loosely) with brightness –Frequency is associated (loosely) with color –Polarization isn’t sensed by humans (but it is by some insects!) Properties of light

8. The spectrum is the range of frequencies of electromagnetic waves Light

9. The eye –curved cornea –lens –retina –fovea –optic disk Using Light

10. Light is focused on the retina by the curvature of the cornea and the lens –Flat lens (relaxed muscles) focuses distant points Using Light

11. Light is focused on the retina by the curvature of the cornea and the lens –Accomodation: Bulged lens (muscles flexed) focuses on near points Using Light

12. Light is focused on the retina by the curvature of the cornea and the lens Constriction of the pupil limits how much light gets in AND reduces the amount of focusing required of the lens Using Light

13. photoreceptors transduce incoming light ganglion cells send signals along to the brain The Retina has layers of cells

14. 2 types of photoreceptors: rods and cones rods are very sensitive - useful in dim light Two kinds of Photoreceptors