1. The Senses Our SENSES tell us: What is out in the environment? How much is out there? Is there more or less of it than before? Where is it? Is it changing in time or place? Other senses?

2. Each of the senses uses specialized receptors to detect relevant incoming stimuli. Sense Receptors in Humans TouchTasteHearing Vision Smell Meissner’s Corpuscle Free nerve ending Rod Cone

3. The Senses Everyone is their own laboratory with which to test the senses. Non-human animals are sensitive to different “energies” in the environment.

4. Energy as Information Forms of energy that can affect cellular processes and thus stimulate sensory systems: Mechanical (touch, pressure, stretch) Electromagnetic (light, magnetic, electrical) Chemical (smell, taste)

5. Vision – The Eye

6. Many Different Kinds of Eyes Different types of structures to detect light Distinctive views of the world needed for survival.

7. Differences in Visible Wavelengths

8. Ultraviolet Insects that feed on flowers, such as bees, have eyes that also can detect ultraviolet Electromagnetic Spectrum

9. Ultraviolet Because bees help pollinate them, flowers display ultraviolet markings that attract and guide the bee to the pollen. http://www.dailymail.co.uk/pages/live/articles/technology/technology.html?in_article_id=473897

10. Infrared Heat (infrared) has longer wavelengths Electromagnetic Spectrum

11. Vision – The Eye

12. 2.5 cm; 7 g

13. Vision – The Eye ? Lens Retina ?

14. Vision – The Eye

15. Rods: most sensitive to light and dark changes, shape and movement and contain only one type of light-sensitive pigment. - not good for color vision. - more numerous than cones in the periphery of the retina. - 120 million rods in the human retina. Cones: are not as sensitive to light as the rods. - cones are most sensitive to one of three different colors (green, red or blue); perception of color; work in bright light. - fine details. - 6 million cones in the human retina. Color Cards

16. Vision – The Eye

17. Location of Rods vs Cones? + + Movement? Color? Detail? 3

18. Vision – The Eye Ishihara Colorblindness Tests

19. Vision – The Eye Optic Disk – no photoreceptors! 

20. Vision – The Brain Right  Left Left  Right

21. Vision – The Brain

22. Path that visual information takes in the brain Primary visual cortex Color area Number appearance area Ramachandran, V.S. and Hubbard Ed (2003), Hearing Colors, Tasting Shapes, Scientific American, Vol 288 Issue 5 (May 2003), 42-49.Hearing Colors, Tasting Shapes

23. Do your eyes fool your brain?

24. Color Aftereffects

25. Adaptation

26. Do your eyes fool your brain?

29. Do you see a triangle?

30. Do your eyes fool your brain? A B C Which line does “A” match up with?

31. It depends on how you look at it!

33. Why Do We Have 2 Eyes? Advantages/disadvantages of eye placement? Blind spot? Depth Perception? Predator vs. Prey

34. Why Do We Have 2 Eyes? Overlapping visual field

35. Depth Perception Monocular/binocular cues? Relative size Interposition Linear perspective Aerial perspective Light and shade Monocular movement parallax