How the environment affects the brain

Not only can the brain determine and change behaviour, but behaviour and

environment can change the brain

Brain plasticity

• Before 1960s, the brain was thought to be unchangeable

• After, the view has changed through many studies on humans and animals.

• Brain plasticity: the brain’s ability to change due to learning or experience

Brain plasticity

• Environmental input can modify the brain, especially the cerebral cortex, which is the area of higher cognitive functioning

• The brain adapts to the New challenges• High levels of stimulation and numerous

learning opportunities at the appropriate times lead to an increase in the density of neural connections

Dendritic branching

• The dendrites of the neurons grow in numbers and connect with other neurons, because…

Every time we learn something new, the neurons connect to create a new trace in the brain.

Example: if you spend a lot of time studying, compared to someone who doesn’t should have a thicker area in the cortex related to that knowledge.

Example of someone who did not get a of of stimulation: Genie

Rosenzweig and Bennet (1972)

• Study on rats (animal experiments)• Enriched (toys) and deprived environment (no

toys)• 30-60 days• Post-mortem studies• Results: one group had increased thickness in

the cortex, frontal lobe (the thickest if they also had company (other rats))

AN EXAMPLE OF THE BRAIN’S PLASTICITY

http://www.youtube.com/watch?v=TSu9HGnlMV0