Brain Hemisphere Organization & the Biology of Consciousness Module 13

13-1 Explain how split-brain research helps us understand the functions of our two brain hemispheres “Of Two Minds”, Sperry & Gazzaniga, 1967 https://www.youtube.com/watch?v=zx53Zj7EKQE https://www.youtube.com/watch?v=u9u6cQYcOHw

“Do not let your left hand know what your right hand is doing “Do not let your left hand know what your right hand is doing.” Matthew 6:3 Split-brain surgery can lead to weird things…. One hand buttons, the other unbuttons One hand selects something, other puts it back Can copy simultaneously two different images (try it yourself…) Two of you sit next to each other, cross the arms that are next to each other (left over right) Now imagine this is one person’s hands….

Handedness http://www.indiana.edu/~primate/left.html

13-2 What is the “dual processing” being revealed by today’s cognitive neuroscience? The principle that information is often simultaneously processed on separate conscious & unconscious tracks Story of D.F.’s blindsight Unable to recognize visually, but could act as if she could Reverse effect Goodale & Milner – visual perception track enables us to think about the world & a visual action track enables movement The “hollow-face illusion” – You’re not going to like it… sight & action don’t always match…

Is the brain ahead of the mind? Experiments show… When you move your wrist, you consciously experience the decision to move it about 0.2 seconds before the actual movement Your brain waves jump about 0.35 seconds before you consciously perceive your decision to move Researchers have been able to (w/ 60% accuracy) predict (sometimes as much as 7 seconds ahead) participants’ decisions to press a button with left or right hand Sometimes consciousness comes after the decision has been made! (Creepy right?) For much of the time we are like an airplane on automatic pilot, but which can be flown manually at any time! (Try doing two conscious-requiring tasks at once…. (circle foot, #3)