1. Split Brain surgery By Livia and Emma IB13

2. What is split-brain surgery? ●a.k.a. corpus callosotomy ●Corpus Callosum is severed ●Used to treat seizures ●Research

3. Roger Wolcott Sperry ●Procedure: 1.Flash one word in each visual field 2.The left visual field is connected to the right hemisphere and vice versa. 3.Subject is asked to find what the word was with his/her left or right hand. ●The first in the field ●Tested on a group with severed/absent corpus callosums and a control group (with normal brains) ●Natural experiment

4. Result ●Left–Right ●Control group could easily pair a word with an object ●In the group without a corpus callosum, hemispheres could not communicate ●Identify with left, describe with right ●Object felt by left hand can only be recognised by left hand

5. Ramachandran ●Study on how the brain hemispheres “talk” to each other ●Is personality and preferences connected to one hemisphere?

6. Why did we get this result? ●Left hemisphere - logic, language … ●Right hemisphere - feelings, imagination… ●Corpus callosum enable exchange of information between the hemispheres. ●Hence, when the corpus callosum is severed, the hemispheres cannot communicate.

7. Information sources http://www.nobelprize.org/educational/medicine/split-brain/background.html http://www.nobelprize.org/educational/medicine/split-brain/background.html (slide --) http://psych.answers.com/neurology/what-is-a-split-brain-operationhttp://psych.answers.com/neurology/what-is-a-split-brain-operation (slide 2,) http://www.psychologytoday.com/blog/the-superhuman-mind/201211/split- brainshttp://www.psychologytoday.com/blog/the-superhuman-mind/201211/split- brains (slide 2) 8.7 “Hemisphere deconnection and unity in conscious awareness” (slide 3,4,6)

8. Image/video sources http://www.intropsych.com/ch02_human_nervous_system/split- brain_operation.htmlhttp://www.intropsych.com/ch02_human_nervous_system/split- brain_operation.html (slide 2) http://wps.prenhall.com/wps/media/objects/2972/3043440//f04_14.jpghttp://wps.prenhall.com/wps/media/objects/2972/3043440//f04_14.jpg (slide 2) http://www.wisegeek.com/what-are-the-functions-of-the-left-brain.htm#http://www.wisegeek.com/what-are-the-functions-of-the-left-brain.htm# (slide 6) https://www.youtube.com/watch?feature=player_embedded&v=PFJPtVRlI64 https://www.youtube.com/watch?feature=player_embedded&v=PFJPtVRlI64 (slide 5) https://www.youtube.com/watch?feature=player_embedded&v=LNZ7QTiaGqE (slide 3) http://hegelperuenglish.blogspot.se/2011/08/have-we-two-brains-3.htmlhttp://hegelperuenglish.blogspot.se/2011/08/have-we-two-brains-3.html (slide 4)

9. Thank you! :)