Download The Biological Approach

The Biological Approach
Natasha G-Q, Sophia, Robert and Katie
Basically...
" You, your joys and your sorrows,
your memories and your ambitions,
your sense of personal identity and free
will, are in fact no more than the
behavior of a vast assembly of nerve
cells and their associated molecules."Crick 1994
History
Louis' Brain
In 1840, Louis Leborgne lost the ability to talk. Until his death in
1861, the only word he could say was "Tan" despite
understanding speech and following instructions.
Paul Broca was interested in Louis and after he died, performed
an autopsy on his brain identifying damage in the left frontal
lobe.
Broca studied a further 25 patients with similar symptoms to
"Tan" and concluded the left frontal lobe was responsible for
speech.
Broca found that certain aspects of behavior are controlled by
different areas within the brain.
Evolution
Charles Darwin travelled to the Galapagos Islands in the mid 19th
century and noticed the different shaped beaks of finches on two of the
islands.
He deduced that the finches were not of different species, but variations
of the same species, how they had modified their bodies (or evolved) to
survive the environment, this is known as “the survival of the fittest”.
Overtime, Darwin saw that the offspring would inherit the traits from their
parents sometimes varying in traits i.e. different sight or hearing, different
tools, so the species could adapt to survive longer. This is known as
natural selection or evolution.
In modern times, humans still share similar (if not identical) traits of our
ancestors, passing them onto our descendants.
Genotype
The collection of all the genes with each cell of an individual.
Genotype
Phenotype
BB
Brown eyes
Same phenotype as below but different
genotype
Bb
Brown eyes
Same phenotype as above but different
genotype
bb
Blue eyes
Different phenotype and genotype from
both above
Phenotype
A description of your actual physical characteristics. This includes
straightforward visible characteristics like your height and eye
color, but also your overall health, your disease history, and even
your behavior and general disposition.
Do you gain weight easily?
Are you anxious or calm?
Do you like cats?
These are all ways in which you present yourself to the world, and
as such are considered phenotypes.
Genetic Influences for Mental Disorders
• Nestadt et al. (2000) found that there is evidence to support biological
influences for Obsessive compulsive disorder (OCD). They found that
siblings and children of people suffering with the condition were 11.7 per cent
more likely to develop the disorder; unlike the 2.7 per cent of the general
population.
Neurochemistry and Behaviours
• The main focus for neurochemistry are chemicals called neurotransmitters.
Neurotransmitters are chemicals such as dopamine, noradrenaline, and
serotonin.
OCD
• Obsessive compulsive disorder is caused by serotonin in low concentrations,
which affects the suppression of the mechanism for task repetition.
• It can be treated with selective serotonin uptake inhibitors. (SSRIs)
Depressions
• Depression is caused by an imbalance in serotonin, dopamine, and
noradrenaline.
• It can be treated with monoamine oxidase inhibitor (MAOIs) and SSRIs.
Contributions
• The biological approach has helped us understand almost every field of psychology across the 20th
century. The human brain is extremely complicated and can influence many types of behaviour.
• 1. Neurosurgery-brain surgery is usually a last resort technique as we know so little about the brain.
H.M. suffered devastating epileptic fits that in the end a surgical technique that had never been used
before was tried out. This technique cured his epilepsy, but in the process the hippocampus had to be
removed which left HM with amnesia affecting his short term memory. Now we know the hippocampus
is involved in memory.
• 2. Electroencrphalograms (EEGs) This is a way of recording the electrical activity of the brain.
Electrodes are attached to the scalp and brain waves can be traced. EEGs have been used to study
sleep and it has been found that during a typical night’s sleep, we go through a series of stages
marked by different patterns of brain wave.
• 3. Brain Scans- More recently methods of studying the brain have been developed using various types
of scanning equipment hooked up to powerful computers. The CAT scan (Computerised Axial
Tomography) is a moving X-ray beam which takes “pictures" from different angles around the head and
can be used to build up a 3-dimensional image of which areas of the brain are damaged.