Discuss the use of brain imaging technologies
(for example, CAT, PET, fMRI) in investigating
the relationship between biological factors and
behavior.
fMRI (Functional
Magnetic Resonance
Imaging)
The fMRI portrays brain activity
indicating the active parts of the
brain which influence behavior.
A three dimensional projected
image of the brain operated
through magnetic fields and radio
waves.
Biological Factors & behavior
A study conducted by Maguire et al. in
the year 2000 utilizes MRI scans to
investigate the relationships between
biological factors and behaviour
The aim was to investigate whether or not the
hippocampus plays a role in human
spatial memory
The target population were London taxi drivers with a
two-year training course and healthy males who did
not drive taxis.
The procedure was to scan the structure of their
hippocampi of both the taxi drivers and the healthy
men.
As a result taxi drivers left and right hippocampi
had a larger volume compared to the
non-taxi drivers. Some parts of the
hippocampi were smaller in the taxi
drivers.
Maguire concluded that there was
probably a redistribution of grey matter in
the hippocampi of taxi drivers due to the
regular use of the spatial memory skills
required to remember roads; the neurons
are stronger in areas of the brain which are
used most.
Biological Factor linked back to brain
areas, such as hippocampi.
Behavior linked back to memory.
CAT (Computerized Axial
Tomography)
Special X-ray tests that produce
cross-sectional images of the brain using
X-rays and a computer.
PET (Positron
Emission
Topography
Illustrates the level of glucose
metabolism in the brain, the higher the
glucose level the higher rate of brain
activity.
A visual colored display
of brain activity where
radioactive tracers are
absorbed.
The red indicates the area with
most brain activity while the
blue areas indicate the least brain activity.
Biological Factors & behavior
A study conducted by Tierney et al. in 2001
which utilizes PET scans to investigate the result
of brain damage.
The aim was to evaluate, using PET scans, the
bilingual language compensation following
early childhood brain damage
The target population were 12 participants, who were fluent in sign
language as well as MA.
The procedure: PET scanning technologies were used while the participants
produced narrative speech or signs.
As a result MA's right hemisphere was more active than the others' during the production of both speech and
sign language.
As a conclusion language function seems to have developed in the right hemisphere instead of the left
hemisphere as an adaptation following his early brain damage
Biological Factor linked
back to damage to brain,
and specific areas. Behavior
linked back to language, and
language acquisition
Background: A 37 year old man (MA)
with normal speech functions
participate in a normal speech study, it was
then discovered that he had a lesion in his left frontal
lobe. A result of encephalitis he
suffered at the age of 6 weeks.
Both his parents were deaf and he used sign
language at home.
Researchers were curious to know if this might
have had something to do with his ability to
speak despite the brain damage, that should
have prevented him from doing so.