More Experience = Bigger Brain?

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
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.
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
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?