Core - Chapter 2 - The Brain and Brain Plasticity Flashcards
Which part of the brain is especially stimulated by environment enrichment?
Cerebral cortex
What is brain plasticity?
The brain’s ability to rearrange the connection between its neurons
How does brain plasticity work?
The density of neural connections increase with high levels of stimulation
What is dendritic branching?
New traces in the brain between neurons created when learning something new.
Describe a study regarding brain plasticity that comes from outer stimulation
Rosenzwieg and Benett (1972)
Describe a study regarding brain plasticity that comes from our own thinking
Richard Davidson (2004)
What are mirror neurons?
A neuron that fires when an animal or person performs and action or when the animal observes somebody else perform the same action
Describe a study on mirror neurons with animals
Gallese et al. (1996)
Describe a study on mirror neurons with humans
Marco Iacoboni (2004)
Why have we developed mirror neurons?
Ramachandran: Play a role in how people react to sports, theatre, video games. Mirror neurons may have evolved to make us capable of understanding and interacting with fellow human beings.
Describe the Mozart effect
The Mozart effect, Rausher et al. (1993)
Has been argued that listening to Mozart will temporarily increase spatial reasoning ability. By listening to the music, the brain will develop a more sophisticated ability to solve spatial problems.
Describe a study contradicting the Mozart effect
Thompson et al. (2001)
Rosenzwieg and Bennett (1972)
Rats were placed in one of two environments to measure the effect of either enrichment (lots of toys) or deprivation (no toys) on the development of neurons in the cerebral cortex.
Rats spent 30 or 60 days in environment. Post-mortem studies showed that the stimulated rats had an increased thickness in the cortex, frontal lobe (thinking, planning, decision making) was heavier. Similar research proves that social interaction further increase the thickness of the cortex.
Limitation: can this be generalized to humans? Only to a certain extent. What is an enriched environment for a human?
Richard Davidson (2004)
Eight buddhist monks highly experienced in meditation, 10 volunteers who had been trained in meditation for a week. All participants were told to meditate on love and compassion. Using a PET scan, Davidson observed that two of the controls and all of the monks experienced an increase in the number of gamma waves (have been linked to higher reasoning faculties) in their brain during meditation. When terminating the meditation the volunteers’ gamma wave production returned to normal, while the monks (who had meditated on compassion for more than 10,000 hours in order to attain the rank of adept) did not experience a decrease. The synchronized gamma-wave area of the monks’ brains during the meditation was found to be larger than the corresponding activation of the volunteers’.
Davidson argues: Meditation could have significant long term effects on the brain and the way it processes emotions.
Brains adapt to stimulation - whether from environment or as a result of our own thinking.
Gallese et al. (1996)
Carried out research on motor neurons, neural messages are electrical in nature, a crackle of the electrical signal when a neuron is activated could be detected. Had isolated the neural response in rhesus monkeys reaching for food (a peanut). Every time the monkey reached for a peanut, the telltale crackling noise was heard. One day, a researcher reached for a peanut and the same crackling noise was produced. By watching somebody else reach for a peanut, the monkey’s brain acted as though the monkey was carrying out the behavior.
Marco Iacoboni (2004)
Asked participants to look at human faces while undergoing and fMRI. Will simply looking at the emotion expressed in someone’s face cause the brain of the observer to be stimulated?
First, participants were asked to imitate the faces they were shown, and then only to look them again. Not only were the same areas of the brain activated in both cases - observing a happy face activated pleasure centers in the brain.
Thompson et al. (2001)
Little to do with Mozart and a more to do with arousal.
When participants’ moods were elevated, they had improved spatial skills; those who’s mood did not change as a result of the music did not show any improvement.
Mozart not an example of plasticity, rather of a heightened sense of attention that increases learning in some people.
Criticism: problems with ecological validity. Laboratory settings and tasks that were not something they would do in the “real world”. May not predict the behavior in a real life situation.
Hubel and Wiesel, 1965
The brain can change as a response to environmental input. Based on laboratory experiments on rats but has now become generally accepted that environmental enrichment can modify the brain, especially the cerebral cortex, which is the area of higher cognitive functioning. It seems like the brain is always changing as a result of experience throughout the lifespan.
Give an example of researchers disproving the brain of being unchangeable
Hubel and Wiesel, 1965
