More Experience = Bigger Brain? An analysis by Oscar “THE BOSS” G.M and Aris “Jean-Pierre” Perez Do experiences produce physical changes in the brain (in other words, does nurture affect our brain’s function)? Background: 1785- Italian anatomist uses dogs from the same litter w/ birds from the same mother and trains each for extended periods of time. The control group was left untrained. The brains were analyzed. Who? 1960s- Team consisting of Mark Rozenweig, Edward Bennett, and Marian Diamond of UC Berkeley utilize new technologies to investigate the same question. Mark Rozenweig The Subjects • • • • More convenient Small and cheap Bear large litters Brains of rats naturally smoother The Experiment A total of 12 rats per condition (3 male rats per litter) for 16 experiments. Kept for 4-10 weeks. 1. Control Group- Standard cage w/ adequate food, constant supply of water. Multiple rats. 2. Impoverished Group- Smaller cage, isolated in a separate room w/ adequate food and constant supply of water. Single rat. 3. Enriched Group- Large cage, w/ variety of objects where they could play (something new placed every day), optimal conditions. 6-8 Rats The Results 1. The cerebral cortex of enriched rats was heavier, thicker, and possessed larger neurons. 2. There was also overall higher chemical activity 3. The synapse was also 50% bigger for enriched rats. Today The study presented new evidence to help shed some light on the issue of nature vs. nurture. The follow-up study comes from researcher Ian Sneddon and his team testing (more complex) pigs when placed in a maze test and tested w/ operant learning tasks. Criticism and Controversy How else could the experimental conditions of the rats account for the differences in brain biology? Are laboratory mice comparable to wild mice? How could this research be used as sensationalistic “pop psychology”? Do rats’ brains reflect what happens in our (human) brains?