Download Connection of study to question

Discuss two effects of the environment on
physiological processes.
Introduction
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State what you are doing in the essay/Introduce Topic
This essay will attempt to offer a considered and balanced review that includes a range of arguments, factors
and hypotheses on two effects of the environment on physiological processes, supported by research studies
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which investigate both effects.
Introduce Topic
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It is said that certain effects of the environment can affect physiological processes such as hormones,
neurotransmitters, but in particular, the human brain. Therefore the relationship between the environment and
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physiology is often said to be “bidirectional,? where environmental enrichment changes the cerebral cortex and
therefore the brain changes our experiences and behaviour. (DEFINE BIDIRECTIONAL)
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The two effects of the environment on physiological processes that will be discussed include:
 Enrichment of certain environments on brain plasticity
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And the observation of experienced actions on the activation of mirror neurons.
Body
EFFECT 1: BRAIN PLASTICITY
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Introduce Topic - Signpost:
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The first effect of an environment on physiological processes that will be discussed is brain plasticity.
Define brain plasticity:
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The brain's ability to rearrange its connections with its neurons; that is the changes that occur in the structure of
the brain as a result of learning or experience (exposure to different environments).
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The changes that can take place are related to the challenges of the environment and thus represent an
adaptation to it.
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Brain plasticity, or neuroplasticity, is the lifelong ability of the brain to reorganize neural pathways based on new
experiences.
Outline brain plasticity
o The brain has the ability to reorganise itself and form new connections between neurons.
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It is stimulated by the environment.
Plasticity occurs every time something new is learnt
Brain plasticity is explicitly shown after brain injury when the brain reorganizes and forms new connections with
healthy neurons to compensate for the functions of the damaged area.
Supporting Study 1: Rosenzweig & Bennett (1972)
Introduce Study - Connection of study to question
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An example of a study which investigates the effects of a deprived or enriched environment on neuroplasticity is an
experiment conducted by Rosenzweig and Bennet (1972).
Aim:
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To investigate the effects of a deprived or enriched environment on neuroplasticity, in particular, the development
of neurons in the cerebral cortex.
Method:
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The participants used were rats (unspecified type).
The independent variable was the type of environment that the rats were exposed to.
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Stimulating environment contained interesting toys
Deprived environment had no toys
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The dependent variable was the weight of the rats? brains, showing the amount of brain plasticity that occurred in
the rats.
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The rats were separated and exposed to the two environments for 30-60 days before being euthanized.
Results:
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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:
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This may have resulted from the exposure to the toys in the stimulating environment, which helped to develop
neural connections in the rat’s brain.
Short Evaluation:
Limitations:
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Lacks ecological validity, because the findings cannot be generalised to humans as the brain and environmental
inputs differ between humans and animals such as rats.
Connection of study to question
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This study showed the effect of the environment on physiology because more enriched environments helped
develop neurons in brains of the rats.
Supporting Study 2: Gaser and Schlaug (2003)
Introduce Study - Connection of study to question:
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Another example of another study investigating the effects of a deprived or enriched environment on
neuroplasticity is a study conducted by Gaser and Schlaug (2003).
Method:
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Compared the brains of professional musicians (who practice at least 1 hr. a day)
Results:
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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
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Connection of study to question
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This study shows how environmental enrichment (in the form of music) contributes to neural connections in the
brain – demonstrating brain plasticity.
Supporting Study 3: Draganski et al. (2004)
Introduce Study - Connection of study to question:
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Another example of a study investigating environmental enrichment on brain plasticity is an study conducted by
Draganski et al. (2004)
Aim:
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To determine whether functional and structural changes could be detected in the human brain as a result of
learning a new motor skill
Method:
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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:
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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
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This difference decreased after 3 months of no practice.
Conclusion:
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Practising watching balls move and learning to move in response has strengthened the neural connections in brain
areas responsible for the activity.
Connection of study to question
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This study demonstrates the effect of enrichment (in the form of juggling) on brain plasticity in participants who
juggled
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Summarize brain plasticity - Link to question: What is the effect of environmental enrichment on brain plasticity
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(physiological process)?
The research studies outlined above demonstrates that the more a person performs a particular activity, the
more neural connections are formed in the area of the brain responsible, creating a physical change in the brain.
This represents the bidirectional relationship between the environment and physiological processes occurring in
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the brain.
EFFECT 2: MIRROR NEURONS
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Introduce Topic - Signpost
Another way in which the brain interacts with the environment has to do with how people learn is through a
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unique physiological process called mirror neurons.
One of the ways that people learn is by observing others and then imitating their behaviour.
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Mirror neurons are special neurons which may play a vital role in the ability to learn as well as empathize with
another person.
Define Mirror Neurons (MN)
o A neuron that fires when an animal (or person) performs an action or when the animal observes someone else
perform the same action; it “mirrors? the behaviour of another.
A small circuit of cells in the premotor cortex and inferior parietal cortex that are activated by the observation or
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performance of a behaviour, internally firing/activating the motor neurons of the corresponding behaviour.
Outline MN
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They activate both when we perform an action and observe someone else performing that same action.
Discovered in 1980s accidentally by a group led by Rizzolatti.
Method:
 They placed electrodes in the inferior frontal cortex of macaque monkeys' brains to study neurons dedicated
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to control of hand movement.
This led to the observation that some neurons responded in the same way when monkeys saw a person pick
up a peanut as when they were doing it themselves
Much research has been done to investigate whether MN are present in humans
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MN help us understand others by providing some kind of inner imitation of actions of other people, which leads
us to "stimulate" the intentions and emotions associated with those actions.
Mirror neurons cannot be directly observed in humans because electrodes cannot be inserted into their brains.
 Magnetic resonance imaging (MRI) of the brain has shown patterns of brain activity consistent with the firing
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of motor neurons (much like in the macaque monkeys)
Thus it has been assumed that MN also exist in humans
MN activate during social learning:
Observational learning - learning through observation and imitation
MN make us feel as though we are performing an action by just observing it - we experience an inner
imitation of the action
The purpose of MN is that it has evolved so that we can better understand and interact with other human
beings.
STUDIES FOR MN
Supporting Study 4: Iacoboni (2004)
Introduce Study - Connection of study to question:
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A study supporting the effect of mirror neurons as a result of observing people’s behaviour is conducted by
Iacoboni (2004).
Aim:
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To determine whether looking at the emotion expressed on someone's face would cause the brain of the observer
to be stimulated.
Method:
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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:
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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
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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.
Supporting Study 5: Keysers (2003)
Introduce Study - Connection of study to question:
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Another set of studies illustrating the effect of mirror neurons are studies conducted by Keysers 2003 & 2004.
Aim:
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Studied MN in relation to the emotion - disgust
Method:
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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:
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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.
Supporting Study 6: Keysers (2004)
Introduce Study - Connection of study to question:
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In 2004, Keysers conducted a similar study, but found that...
Results:
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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:
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This suggests that understanding experiences and emotions of others and ourselves is mediated by mirror
neurons
Connection of study to question
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The study shows that observing the film of someone touching another's leg (environmental stimuli) after
experiencing the action activated the mirror neurons (physiological process) in the participants' brains.
Supporting Study 7: Simon et al (2006)
Introduce Study - Connection of study to question:
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In 2006, Simon et al. conducted a study of how (insert method) the anterior cingulate cortex awake human
subjects.
Method:
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Studied the anterior cingulate cortex of awake human subjects,
Results:
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Certain neurons that typically fire in response to pain also fired when the person saw someone else in pain.
Connection of study to question
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The study shows that the same neurons fire in response to pain for a variety of human subjects, which reinforces
how the environment affects physiological processes similarly across most humans.
STUDIES AGAINST MN
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Introduce Argument Signpost:
o However, there have been some arguments, theories and evidence against MN?s.
Supporting Study 8: 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
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other way round.
This suggests that the system is merely priming the motor neurons for subsequent activity.
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MN have been used to explain language, culture and empathy
o But although monkeys have mirror neurons, they don't have language, culture or empathy.
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There are other ways of understanding and explaining other people's actions than MN.
o The MN system is not needed
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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.
Conclusion
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In conclusion the two discussed effects of the environment on physiological processes are:
o Enrichment on brain plasticity
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Observation of experienced actions on the activation of mirror neurons
Neuroplasticity is the brain's ability to reorganize neural pathways (physiology) based on new experiences
(environment).
The interaction occurs when the enriched environments affect the neural connections in the brain by
reorganising the neural connections in brain areas related to functions that are required in the enriched
environment/condition.
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Mirror neurons in the brain activate (physiology) when we perform an action and observe someone else
performing that same action (environment) and therefore “mirror? the behaviour of another individual.
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MN makes us feel as though we are performing an action by just observing it - we experience an inner imitation
of the action.
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The relationship exists when observing another person’s behaviour in the environment which therefore
generates a response from the neurones in our brains, which are physiological processes of behaviour.
Answer the question
o It can therefore be stated, as a result of the supporting studies and theories that a bidirectional relationship
exists between the environment and physiological processes, forming a strong interaction.