2. EXP3202 Sensation and Perception Course Website www.psy.fsu.edu/~johnson/snp Read ‘Course Objectives’ Lecture/Lab: 1 Grade 3 Unit Exams (multiple choice) and a Final Exam (essay) Unit Exam Forgiveness ‘Schedule’ Page Lecture Topics and Reading Assignments Links to ‘Chapter Websites’ for Book Chapters ‘Lecture Download’ Page Download Lecture Slides

3. EXP3202 is a Psychology Course What is Psychology?

4. 0 20 40 60 80 100 01K2K3K4K5K Chemical Element No. Recorded History R. Buckminster Fuller Key Points 1.As psychologists, we are doubting and questioning something that appears to be changing rapidly, with no obvious end in sight. Not true of other sciences. A warning to psychologists who think it is their job to explain the present. 2.Nothing about the human brain predicted this change, but this change would have been impossible without it. Psychological evolution? Biological Evolution? Both? 3.PSYCHOLOGY seeks to understand how this potential for change is built into the human brain, and why it was dormant for most of human history.

5. EXP3202 is a Psychology Course Why is Sensation and Perception Important for Psychology?

6. What is real? We only experience the reality that is created by our brains. The physical sciences (Physics, Chemistry) have enabled us to ‘see’ the world as it truly exists. ‘Psychophysics’ allows us to establish relationships between our ‘true’ brain- based reality and the ‘true’ physical world. These relationships are rarely linear (i.e., the brain does not function as a ‘mirror’).

7. After this course, you can no longer be a ‘naïve realist’ although maybe you didn’t know you were one… Fechner’s Law S = k log R “Psycho = log Physics” Steven’s Power Law S = a I b “Psycho = Physics b ” Only in rare instances does “Psycho = Physics” OK, so what does this mean? It means that our brains are often either exaggerating small physical differences, and/or understating large physical differences.

8. Overview The BIG PICTURE

9. Perception! (Synthesis) Sensation (Analysis) Receptor Neurons PSYCHOPHYSICS Energy Things vibrating (hearing) Things bumping into other things (touch) Matter Atoms and Molecules (pain, taste, smell) Photons* (vision) Now you’re dreaming... ‘The Matrix’ Your WorldThe Real World We only experience the reality that is created by our brains.

10. Perception! (Synthesis) Sensation (Analysis) Receptor Neurons PSYCHOPHYSICS Energy Things vibrating (hearing) Things bumping into other things (touch) Matter Atoms and Molecules (pain, taste, smell) Photons* (vision) Your WorldThe Real World A Drug

11. OK – so we are made of cells… Bags of Water that Consume, Transduce, Store, Expend Energy Make Proteins (DNA-RNA-Protein) Make More Cells

12. How can we use cells to sense the world? Neurons: Yes/No/Mo’ Sensory ‘Transducers’ - ‘matter’ and ‘energy’ in the physical world become a pattern of electrical signals Organize Receptor Neurons as 2D Sheets of Cells Stimuli Encoded as 2D Maps of Electrical Activity NOTE: Impossible for Sensory Receptors to Encode 3D, But In Some Cases We Perceive 3D – How?

13. A 2D Sheet of Sensory Neurons (Yes/No Responses) The Stimulus as been ‘broken down’ into a 2D Map of Neural Activity! Of course, this gets a little more complicated if we are talking about a real visual stimulus… what if you were looking at a picture of my grandmother?

14. Of course, this gets a little more complicated if we are talking about a real visual stimulus…

15. A 2D Sheet of Sensory Neurons (Mo’ response codes intensity) The Stimulus as been ‘broken-down’ into a 2D Map of Neural Activity! Stimulus intensity coded by firing rate!

16. A 2D Sheet of Sensory Neurons (Yes/No Responses) The Stimulus as been ‘broken-down’ into a 2D Map of Neural Activity! To ‘perceive’ the stimulus we simply reverse the process!

17. LEARN THIS NOW: There are only a few ways to connect neurons. Here are the major ways to do it, with example functions. 1:1 (relay) Many:1 (gain - sensation, complexity - perception) 1:Many (arousal)

18. 1.Sensation = Analysis. Perception = Synthesis. 2.Sensation: Detect or Identify? 3.Perception: Model or Representation? Final Words: Because we’re using ‘dumb’ cells in a complicated world – Division of labor and compromise.