Download Discuss two effects of the environment on physiological processes

Discuss two effects of the
environment on physiological
processes. (22)
Discuss (22) – A considered and balanced review, including a range of arguments, factors or
hypothesis. Opinions and conclusions presented clearly supported by appropriate evidence.
https://www.youtube.com/watch?v=ELpfYCZa87g
https://www.youtube.com/watch?v=9r1UMS5z3
https://www.youtube.com/watch?v=BLDi8erFA
Draganski et al. (2004) – brain changes
after learning a new motor skill
https://www.youtube.com/watch?v=dAkYL7m5rK4
Draganski et al. (2004) – brain changes
after learning a new motor skill
Aim:
•To determine whether functional and structural changes could be detected in the human brain as a result of
learning a new motor skill
•Method:
•21 females and 3 males were split into two groups
One group had to spend 3 months learning a juggling routine for a minimum of 60 seconds, then spend 3
months not practising juggling
Results:
•MRI scans showed no structural differences in groups' brains before juggling.
•There was an increase in volume of two regions of the jugglers' brains associated with the retention
of visually detected movement information of learning
• This difference decreased after 3 months of no practice.
Conclusion:
•Practising watching balls move and learning to move in response has strengthened the neural connections in
brain areas responsible for the activity.
Rosenzweig & Bennett (1972) effects of a
deprived or enriched environment on rat’s
neuroplasticity
Rosenzweig & Bennett (1972)
Aim:
•To investigate the effects of a deprived or enriched environment on neuroplasticity, in particular, the
development of neurons in the cerebral cortex.
Method:
•The participants used were rats (unspecified type).
•The independent variable was the type of environment that the rats were exposed to.
• Stimulating environment contained interesting toys
• Deprived environment had no toys
The dependent variable was the weight of the rats brains, showing the amount of brain plasticity that occurred
in the rats.
The rats were separated and exposed to the two environments for 30-60 days before being euthanized.
Results:
•Rats in the stimulating environment had a thicker cortex and heavier frontal lobe (associated with thinking,
planning, and decision-making) compared to rats in the deprived environment.
Conclusion:
•This may have resulted from the exposure to the toys in the stimulating environment, which helped to develop
Gaser and Schlaug (2003) – grey matter
volume in musicians
Gaser and Schlaug (2003)
Method:
•Compared the brains of professional musicians (who practice at least 1 hr. a day)
Results:
•Grey matter volume was:
• highest in the professionals' brains
• lowest in the non-musicians
• in several brain areas involved in playing music such as motor regions, anterior superior
parietal areas and inferior temporal areas
Connection of study to question
•This study shows how environmental enrichment (in the form of music) contributes to neural connections
in the brain – demonstrating brain plasticity.
Iacoboni (2004)
Aim:

To determine whether looking at the emotion expressed on someone's face would cause the brain of the observer to be
stimulated.
Method:

Asked participants to look at human faces while in an fMRI.

Participants had to imitate the faces shown and then they watched as the faces were shown again.
Results:

The same brain area was activated both times (in both animals and humans).

The limbic system was stimulated - observing a happy face activated pleasure centres in the brain.
Connection of study to question

This study demonstrates the effect of observing experienced actions on mirror neurons as the participants' mirror neurons were
activated when they observed and imitated facial expressions.
Iacoboni (2004) – brain stimulation by
viewing facial expression
Keysers (2003)
Keysers (2003)- MN in relation to
disgust
Aim:

Studied MN in relation to the emotion - disgust
Method:

He put his volunteers in a brain scanner and wafted disgusting odours


For example, rancid butter and rotten eggs into their nostrils
He wafted some non-disgusting ones too, as a control
Results:

The disgusting odours, he found, activated part of the brain called the anterior insula.

He then played film clips of people's faces registering disgust to his volunteers, and found
activity in exactly the same part of the brain.
Keysers (2004)
•In 2004, Keysers conducted a similar study, but found that...
Results:
•Part of the brain that was activated by touching the leg of a person in a brain scanner also reacted if the subject was shown film of
another person being touched on the leg.
Conclusion:
•This suggests that understanding experiences and emotions of others and ourselves is mediated by mirror neurons
Lingau et al (2009)
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Lingau et al (2009) did not find mirror neuron activity for acts that were first done and then
observed, only the other way round.
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MN have been used to explain language, culture and empathy


But although monkeys have mirror neurons, they don't have language, culture or empathy.
There are other ways of understanding and explaining other people's actions than MN.
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This suggests that the system is merely priming the motor neurons for subsequent activity.
The MN system is not needed
Neuroimaging techniques have provided evidence to suggest that MN exist in humans

However, fMRI studies cannot prove the existence of mirror neurons – only the oxygen use of
sections of the brain with many neurons.