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‘All that is psychological is first
physiological’
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MRI
fMRI
Discuss the use of brain imaging technologies in
investigating the relationship between biological
factors and behaviour.
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Non-invasive procedures
Can be used to:
◦ Measure brain activity
◦ Look at brain structures
◦ Discover function of brain areas
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These techniques are very useful to
psychologists as they allow study of the brain
which is within the ethical guidelines of the
British Psychological Society and international
equivalents.
https://www.youtube.com/watch?v=Rmx8vgTqAE
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Cannot be done in 21st century because can
be very dangerous
Invasive procedures include:
◦ Electroconvulsive therapy: electric shock given
through electrodes
◦ Psychotherapy: includes lobotomies and lesioning
by which sections of brain are removed and
behaviiur is compared before and afterwards
Can
Do
Can’t
Do
With
Participants
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Modern technology is now extensively used in
neuropsychology
Useful because it allows researchers to study
active brain:
◦ See where specific brain processes take place
◦ Enables localisation of function in LIVING brain
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Each has its own advantages and disadvantages
and is appropriate in varying situations
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Electroencephalogram (EEG)
Positron Emission Topography (PET)
Magnetic Resonance Imaging (MRI)
Functional Magnetic Resonance Imaging (fMRI)
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Cannot be fully described as a brain imaging
technique as does not show an image of brain
Instead shows an image of electrical activity in
brain
When neurons transport information through
the brain, they have an electrical charge
Registers patterns of voltage change in the brain
Strengths
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Relatively easy to carry out procedure
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Psychologists have gained better understanding of
behaviours as diverse as sleep, emotions &
epilepsy
Limitations
 Provides limited information-cannot show brain
structures so electronic activity cannot be localised
to a particular part of brain
 Can only show surface brain regions and can’t show
electrical activity in deeper structures of brain such
as the corpus callusum
Monitors glucose metabolism in brain
 Patient injected with harmless dose of
radioactive glucose tracer
 Shows areas where glucose is absorbed in
active brain
More glucose= more brain activity
 Used to diagnose
abnormalities like tumors,
Alzheimer’s,
schizophrenia etc
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PET shows a coloured visual display of brain
activity:
◦ Red indicates most activity
◦ Blue indicates least activity
Strengths
 High resolution
 Can be used for detection of disorders
like Parkinson’s disease
Limitations
 Invasive (injection)
 Very expensive
 Injection is radioactive isotope. Although within safety
levels there is a limit to number of injections you can
have
 Any exposure to radiation carries a very small risk of causing
damage to tissues and the possibility of triggering a new cancer.
 However, in a standard PET scan the amount of radiation you
are exposed to is the same as the amount received from natural
sources, such as the sun, over the course of three years.
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Uses a magnetic field and radio waves to
create detailed images of the body.
Gives detailed pictures of internal structures
in brain
People remove all metal objects and clothing
and lie within an MRI machine
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Used MRI to investigate whether substance abuse (marijuana) can
damage developing brain of young adults
Study Group
Control Group
14 young men with history of heavy marijuana
abuse over long period of time
14 young men who had no history of marijuana
use
Scan indicated that there were brain abnormalities in frontal,
parietal and temporal regions in brain of marijuana users
Development of white matter (myelin*) was affected could explain
slow information processing in brain
Concluded that early marijuana use can affect brain development
but as study gives correlational data more research is needed
*Remember: Myelin sheath covers neuron and
helps to speed up neurotransmission
Case study of H.M.
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Corkin et al (1997) did MRI scan of H.M’s
brain which allowed for precise picture of
brain damage. Confirmed that hippocampus
was missing- able to link to memory.
Perry (1997)
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Brain scans of three year olds who had a
normal upbringing and those who were
severely neglected
Found differences in brain size and
development
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MRI scans show how blood flows in brain and can
be used to identify problems with blood
circulation. Can be used for early detection of
Alzheimer’s
Non-invasive
Individuals can be tested repeatedly
Practical and easy to use most hospitals already
have them
Fast 1/2 mins most of brain
Safe to use as no radioactive material is used
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Scanner not a natural environment for
cognition- question of ecological
validity
Very expensive
Movement may affect images
Cannot be used on everyone
claustrophobic people, obese people
patients with pacemakers or metallic
implants cannot be studied due to
magnetic fields
Cannot say anything about cause and
effect relationships, only provide
correlational data
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Scanner measures changes in
blood flow in active brain
Blood flow associated with use of
oxygen and neural activity
during information processing
When participants are asked to
perform a task, scientists can
observe the part of the brain that
corresponds with that function
Use increased vastly over past
ten years and now widely used
by cognitive neuroscientists
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Magnetic Resonance Imaging (MRI) provides pictures of
structures inside the body, while functional Magnetic Resonance
Imaging evaluates metabolic processes.
MRI can be used anywhere in the body, while fMRI studies
concentrate on the brain.
In an MRI scan, the goal is to get an image of anatomical features
in a given area of the body. The equipment can be used to
generate high-resolution images where various organs will
appear as clearly distinct from each other, and abnormalities like
tumors can be easy to spot.
fMRI looks specifically at blood flow in the brain and is capable
of detecting very small changes. This allows the test to identify
when different areas of the brain become active, which can help
a doctor or researcher see what a patient’s brain is doing.
MRI and fMRI are typically ordered for very different reasons.
fMRI study of neurobiological mechanism of attraction
Aim:
 To investigate the neural mechanisms associated with the attraction system
(romantic love).
Procedure:
 Participants were 10 women and seven men aged from 18 to 26, who reported
being in love for an average of 7.5 months.
 Participants first filled out a questionnaire (The Passionate Love Scale) to
investigate how they felt about their relationship.
 Then they were placed in the fMRI scanner.
 They first looked at a photograph of their beloved, then performed a distraction
task of counting backwards, and finally they looked at a photograph of a neutral
acquaintance. This was repeated six times.
Results:
 Increased activity in the dopamine rich brain areas associated with reward,
motivation, and goal orientation (dopamine-rich areas associated with mammalian
reward and motivation) when participants looked at their lover.
 The results indicate the possibility of brain circuits dedicated to attraction
(romantic love). The same brain circuits have been associated with “addiction”,
which could support the hypothesis that “romantic love is an addiction”. Fisher
argues that “romantic love” is universal and based on neurobiological factors.
Baumgartner et al (2008) Oxytocin and Trust
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fMRI scans carried out on participants
In oxytocin group cans showed decreases in
responses in amygdala (involved in emotional
processing) and caudate nucleus (involved in
learning to trust)
Explanation for behaviour in trust game
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One of most frequently used technologies in
biopsychological research today
Shows actual brain activity and indicates
which areas of brain are active
Scans have higher resolution than PET scans
and are easier to carry out
Does not use radioactive substances
Can record activity in all regions of brain
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Focus mostly on localised functioning in brain
and does not take into account the distributed
nature of processing in neural networks
Results are correlational so not possible to
establish cause and effect relationships
Scanner not a natural environment for cognitionquestion of ecological validity
Brain areas activate for different reasons- e.g.
Just because amygdala lights up does not
necessarily mean fear is the response being
observed
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Different brain imaging methods each have
own strengths and limitations
Different methods suitable for different
purposes
Brain scanning techniques have allowed
researchers to learn more about brain and
biological links to behaviour