The Biological Physiological Approach

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The Biological (Physiological) Approach
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• As knowledge of human anatomy, biochemistry,
  physiology genetics increased and advances in
  medicine were made, insights into human behaviour
  and experience were gained.

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Assumptions-

• All that is psychological is first physiological
  all thoughts, feelings, and behaviours
  ultimately have a physiological/biological cause.
• Human genes have evolved over millions of years
  to adapt physiology and behaviour to the
  environment, therefore, much of human behaviour
  will have a genetic basis.

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• It is therefore useful to study
• the brain, nervous system, endocrine system,
  neurochemistry and genes.
• the evolutionary significance of behaviours, why
  has a behaviour evolved as it has,
  evolutionary/sociobiological theory.

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• These areas of investigation should be studied
  using
• laboratory experiments (e.g. monitor the effect
  of a particular drug on behaviour),
• laboratory observations (e.g. sleep
  investigations),
• correlations (e.g. twin studies to discover the
  genetic influence in eating disorders)

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Main areas of study for the Bio-psychologists-

• CNS (Brain Spinal Cord)
• Brain can be studied using
• invasive techniques
• Lesions, electrical chemical stimulation
• non-invasive techniques
• CAT, PET, MRI, EEG, angiogram
• Split brain studies lateralisation of function
• Localisation of function ( e.g. sensory cortex,
  motor cortex, visual cortex, language areas )

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• PNS (nerves)
• Somatic Nervous system
• Autnomic nervous system
• Sympathetic branch (prepares for action)
• Parasympathetic branch (restores balance)

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• The structure of nerve cells (neurons)
• Neurotransmitters in the Nervous system

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• The Endocrine System-
• Glands which hormones they produce
• Hormones their effects
• The interaction between the endocrine system
  the nervous system

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• Genetics
• The study of genes and chromosomes,
  identification of the involvement of particular
  genes in human behaviour and more likely the
  interaction of genes in human behaviour.

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Really useful websites-

• http//www.enchantedlearning.com/subjects/anatomy/
  brain/Neuron.shtml
• http//faculty.washington.edu/chudler/neurok.html

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The Structure of the Nervous System
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Copy the diagram and put the terms from the
bottom of the screen in the correct boxes.
Autonomic nervous system, Somatic nervous system,
Spinal cord, Brain, Parasympathetic nervous
system, Peripheral nervous system, Sympathetic
nervous system, Central nervous system, Nervous
system.
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The Neuron look at the diagram in the handout
Direction of impulse
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The neuron - some facts copy these down

• There are billions of neurons in the nervous
  system
• 80 of neurons are in the brain
• A nerve is a bundle of neurons

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• There are 3 main kinds of neurons
• Sensory (afferent) neurons
• Motor (efferent) neurons
• Inter (connector neurons)
• They vary in size from 4 microns (.004 mm) to 100
  microns (.1 mm) in diameter. Their length varies
  from a fraction of an inch to several feet.

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• Unlike most other cells, neurons cannot re-grow
  after damage (except neurons from the
  hippocampus). Fortunately, there are billions of
  neurons in the brain.
• Information is passes from neuron to neuron by
  electrochemical transmission.

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Neural Transmission the action potential
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The Na and K channels are also called
voltage-activated gates because they act only
when the surrounding area reaches a certain
voltage.   The point at which the Na channel
opens (1 on diagram) is called the threshold of
excitation (about -40 mV).   When the sodium
ions pour into the neuron (1 to 2 on diagram),
only a very small percentage of ions actually do
so. The concentration of Na ions inside
increases by only about 1.
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What are some real-world implications of
this? Some nerve poisons (e.g., scorpion venom)
open Na channels and shut K channels disrupts
any action potentials.   Local anesthetic drugs
(Novocain, Xylocaine) block the Na channels and
prevent action potentials along sensory
neurons.   General anesthetics used in
hospitals (ether, chloraform) open some K
channels in the brain a bit wider than usual.
This counter-acts the effects of Na channels
being opened and prevents action potentials from
propagating, too.
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All or None Law Axons either "fire" or they
don't "fire" to use the metaphor of a gun. If
they do "fire," then the size and speed
(amplitude and velocity) of the resulting action
potential along an axon is relatively invariant.
Stronger stimuli do not increase either the size
or the speed. This is what the "All or None Law"
states.    How, then, does a neuron signal a
stimulus of stronger intensity? By firing more
frequently. Frequency (i.e., the number of action
potentials per second) conveys the strength of
the original stimulus while each action potential
moves at the same speed and has the same "size".

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So far, we've looked at an action potential as it
is generated at one place the axon hillock.
How does it propagate or "move" down the axon?
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Look at the diagram to the left. An action
potential propagates along an axon by a process
in which, once triggered, the influx of positive
ions causes the adjacent Na gate to open and, in
turn, this causes the next Na gate to open, and
so on. Hence, an action potential is actually
self-propagating.
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How fast does an action potential move along an
axon? The thinnest axons propagate an action
potential at less than 1 meter per second (1
m/s).    Thick axons propagate action
potentials at about 10 m/s.  However, myelin
sheaths permit speeds up to 100 m/s. HOW?
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Saltatory conduction When the Na ions enter the
inside of the axon, they quickly spread. The
insulation of the myelin allows the ions to move
quickly to the next Na gate at a node of
Ranvier. And, so, the action potential jumps from
one node to the next.
By the way, the Latin word, saltus, which is the
origin of "saltatory," means "a jump".
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How is a neuron triggered off and what happens
when the action potential reaches the end of the
axon?

• A typical neuron has about 1,000 to 10,000
  synapses (that is, it communicates with
  1,000-10,000 other neurons, muscle cells, glands,
  etc.).
• A neuron will add up the input from these
  synapses, some will be stimulating the neuron and
  others will be inhibiting the neuron. Only if the
  THRESHOLD of stimulation is reached, will the
  neuron fire.

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The Synapse look at the diagram in the handout
Vesicle
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How does the synapse work? Look at the hand out
and try to put the steps of the synaptic process
in the correct order.
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• The transmitter substance is made and stored in
  the vesicles
• The Action Potential arrives at the synapse.
• The Transmitter substance is released from the
  vesicles.
• The Transmitter substance flows across the
  synaptic cleft.
• The Transmitter substance attaches to the
  appropriate receptor sites on the post synaptic
  membrane (lock key principle).
• The post synaptic neuron summates the excitatory
  and inhibitory input in order to decide whether
  or not to fire.
• The Transmitter substance is reabsorbed into the
  vesicles of the synaptic button.

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Examples of Transmitter substances

• Acetylcholine at neuron muscle synapses
• Dopamine found throughout the brain, important
  in movement and other behaviours
• Serotonin found throughout the brain, important
  in many behaviours including mood, sleep,
  alertness
• Noradrenaline works in the brain and plays a
  crucial role in arousing the body, or example
  from sleep. High levels hypersensitivity, low
  levels poor concentration and depression.

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Examples of when things go wrong

• Parkinsons disease gradual degeneration of one
  pathway through the brain of dopamine containing
  neurons. Results in an inability to initiate and
  control movements causing rigidity and tremors.
  It is not yet possible to cure this disease. The
  symptoms can be managed to a degree in less
  severe cases.

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• Myasthenia Gravis an auto immune disease where
  the patient produces antibodies that attack the
  Acetylcholine receptors at nerve muscle
  junctions. This causes weakness and rapid muscle
  fatigue.

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How is the Brain Studied?

• Clinical case studies
• people with brain damage compare behaviour
  before after damage.
• Useful but limitations include-
• can not predict when damage will occur therefore
  will not have detailed analysis of behaviour
  prior to the damage.
• can not control site and extent of damage
• Must wait for damage to happen to the unfortunate
  individual

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• Invasive Methods
• Ablation surgical electrical
• Lesions surgical electrical
• Stimulation electrical chemical
• All very useful and fairly specific. Look at the
  behaviour changes occurring with the alteration
  in the brain.
• Microelectrode recording of individual neurons.
• Look at the electrical output of the individual
  neuron when a behaviour is performed.
• Limitations- involve surgical operations to
  access the brain and therefore can not easily be
  used on human participants. Mostly used with
  animals or patients who need brain surgery for
  some medical reason.

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• Non- Invasive Methods
• EEG (Electroencephalogram) recording of the
  electrical activity of the whole brain.
• Scanning and Imaging techniques, e.g.
• CAT
• PET
• MRI
• Do not involve surgery but may involve
  injections (into the blood stream) of materials
  that can be detected by the scanners. Advanced
  computer technology means that complex 3D images
  can be developed which show the activity in the
  brain.
• Unfortunately these techniques are still very
  costly.

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The structure of the BRAIN
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Localisation of Function

• is the idea that specific parts of the brain
  have specific functions. (See handout)
• For example-
• THE CEREBELLUM
• Balance
• Posture
• Cardiac, respiratory, and vasomotor centers

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• Hypothalamus
• Moods and motivation
• Sexual maturation
• Temperature regulation
• Hormonal body processes
• Pituitary Gland
• Hormonal body processes
• Physical maturation
• Growth (height and form)
• Sexual maturation
• Sexual functioning

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Frontal Lobe

• Behaviour
• Abstract thought processes
• Problem solving
• Attention
• Creative thought
• Some emotion
• Intellect
• Reflection
• Judgment
• Initiative

• Inhibition
• Coordination of movements
• Generalized and mass movements
• Some eye movements
• Sense of smell
• Muscle movements
• Skilled movements
• Some motor skills
• Physical reaction
• Libido (sexual urges)

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Parietal Lobe

• Sense of touch (tactile senstation)
• Appreciation of form through touch (stereognosis)
  
• Response to internal stimuli (proprioception)

• Sensory combination and comprehension
• Some language and reading functions
• Some visual functions
• See handout

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• Temporal Lobe
• Auditory memories
• Some hearing
• Visual memories
• Some vision pathways
• Other memory
• Music
• Fear
• Some language
• Some speech
• Some behavior amd emotions
• Sense of identity

• Occipital Lobe
• Vision
• Reading

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Localisation of Language in the Brain

• Patients with speech problems gave early
  researchers the first clues about how the brain
  is involved with language. The loss of the
  ability to speak is called "aphasia." The ancient
  Greeks noticed that brain damage could cause
  aphasia. Centuries later, in 1836, Marc Dax
  described a group of patients who could not speak
  properly. Dax reported that all of these patients
  had damage to the left side of their brain. A
  quarter century later in 1861, Paul Broca
  described a patient who could say only one
  word..."tan." For this reason, Broca called this
  patient "Tan." When Tan died, Broca examined his
  brain and found that there was damage to part of
  the left frontal cortex. This part of the brain
  has come to be known as "Broca's Area."

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• In 1876, Karl Wernicke found that damage to a
  different part of the brain also caused language
  problems. This area of the brain ("Wernicke's
  Area"), was further back and lower in the brain
  compared to Broca's area. In fact, Wernicke's
  area is in the posterior part of the temporal
  lobe. Broca's area and Wernicke's area are
  connected by a bundle of nerve fibers called the
  arcuate fasciculus. Damage to the arcuate
  fasciculus causes a disorder called conduction
  aphasia. People with conduction aphasia can
  understand language, but their speech does not
  make sense and they cannot repeat words.

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To speak a word that is read, information must
first get to the primary visual cortex. From the
primary visual cortex, information is transmitted
to the posterior speech area, including
Wernicke's area. From Wernicke's area,
information travels to Broca's area, then to the
Primary Motor Cortex.
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To speak a word that is heard, information must
first get to the primary auditory cortex. From
the primary auditory cortex, information is
transmitted to the posterior speech area,
including Wernicke's area. From Wernicke's area,
information travels to Broca's area, then to the
Primary Motor Cortex.
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The language problems associated with damage to
Broca's and Wernicke's area are quite different
from one another

• Damage to Broca's Area(Broca's aphasia)
• prevents a person from producing speech
• person can understand language
• words are not properly formed
• speech is slow and slurred.

• Damage to Wernicke's Area(Wernicke's aphasia)
• loss of the ability to understand language
• person can speak clearly, but the words that are
  put together make no sense. This way of speaking
  has been called "word salad" because it appears
  that the words are all mixed up like the
  vegetables in a salad.

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Lateralisation of Function in the brain

• WHAT IS BRAIN LATERALIZATION?
• The human brain is a paired organ it is
  composed of two halves (called cerebral
  hemispheres) that look pretty much alike.
• The term brain lateralization refers to the fact
  that the two halves of the human brain are not
  exactly alike. Each hemisphere has functional
  specializations some function whose neural
  mechanisms are localized primarily in one half of
  the brain.

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Right Side - Left Side The right side of the
brain controls muscles on the left side of the
body and the left side of the brain controls
muscles on the right side of the body. Also, in
general, sensory information from the left side
of the body crosses over to the right side of the
brain and information from the right side of the
body crosses over to the left side of the brain.
Therefore, damage to one side of the brain will
affect the opposite side of the body.
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In humans, the most obvious functional
specialization is speech and language abilities.

• Most humans (but not all) have left hemisphere
  specialization for language abilities.
• The only direct tests for speech lateralization
  are too invasive to use on healthy people, so
  most of what we know in this area comes from
  clinical reports of people with brain injuries or
  diseases.
• Based on these data, and on indirect measures, we
  estimate that between 70 to 95 of humans have a
  left-hemisphere language specialization.

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• An unknown percentage of humans (maybe 5 to 30)
  have anomalous patterns of specialization. These
  might include (a) having a right-hemisphere
  language specialization or (b) having little
  lateralized specialization.
• The more one knows about the neurological
  mechanisms underlying language abilities, the
  more complicated these issues become. For
  instance, some language functions (like prosody--
  the emotive content of speech) is specialized in
  the right hemisphere of people with
  left-hemisphere language specializations.

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• Much of what we know about the right and left
  hemispheres comes from studies in people who have
  had the corpus callosum split
• - this surgical operation isolates most of the
  right hemisphere from the left hemisphere.
• This type of surgery is performed in patients
  suffering from epilepsy. The corpus callosum is
  cut to prevent the spread of the "epileptic
  seizure" from one hemisphere to the other.
• This technique was pioneered by Roger Sperry
  Michael Gazzaniga in the 1960s.

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The participant fixates a center dot and then
sees a picture or a word on the right or left
side of the dot. He may be asked to respond
verbally, by reading the word or naming the
picture. He may also be asked to respond without
words, for example, by picking out a named object
from among a group spread out on a table and
hidden from view, so that it can only be
identified by touch.
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So, say a "typical" (language in the LEFT
hemisphere) split-brain patient is sitting down,
looking straight ahead and is focusing on a dot
in the middle of a screen. Then a picture of a
spoon is flashed to the right of the dot. The
visual information about the spoon crosses in the
optic chiasm and ends up in the LEFT HEMISPHERE.
When the person is asked what the picture was,
the person has no problem identifying the spoon
and says "Spoon." However, if the spoon had been
flashed to the left of the dot (see the picture),
then the visual information would have travelled
to the RIGHT HEMISPHERE. Now if the person is
asked what the picture was, the person will say
that nothing was seen!!
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But, when this same person is asked to pick out
an object using only the LEFT hand, this person
will correctly pick out the spoon. This is
because touch information from the left hand
crosses over to the right hemisphere - the side
that "saw" the spoon. However, if the person is
again asked what the object is, even when it is
in the person's hand, the person will NOT be able
to say what it is because the right hemisphere
cannot "talk." So, the right hemisphere is not
stupid, it just has little ability for language -
it is "non-verbal."
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• Despite these overly-simplistic descriptions of
  left-brain / right-brain often published in books
  and the press, there is still a great deal about
  brain lateralization that we simply do not yet
  understand.

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In your workbook read the section on the work of
Roger Sperry and then answer the following
questions on lined paper. Hand in your work.

• In your own words explain what Sperry was trying
  to demonstrate.
• Describe the corpus callosum explain why it was
  cut.
• In your own words explain how Sperry tested these
  individuals.
• Describe any two different findings from these
  studies.
• Write one positive and one negative evaluative
  statement of the studies.

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The Autonomic Nervous system

• The organs (the "viscera") of our body, such as
  the heart, stomach and intestines, are regulated
  by a part of the nervous system called the
  autonomic nervous system (ANS).
• The ANS is part of the peripheral nervous system
  and it controls many organs and muscles within
  the body.
• In most situations, we are unaware of the
  workings of the ANS because it functions in an
  involuntary, reflexive manner. For example, we do
  not notice when blood vessels change size or when
  our heart beats faster. However, some people can
  be trained to control some functions of the ANS
  such as heart rate or blood pressure

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• The ANS regulates
•                     
• Muscles
• in the skin (around hair follicles smooth
  muscle)
• around blood vessels (smooth muscle)
• in the eye (the iris smooth muscle)
• in the stomach, intestines and bladder (smooth
  muscle)
• of the heart (cardiac muscle)
• Glands
• The ANS is divided into two parts
• The sympathetic nervous system
• The parasympathetic nervous system

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The Sympathetic Nervous System
It is a nice, sunny day...you are taking a nice
walk in the park. Suddenly, an angry bear
appears in your path. Do you stay and fight OR do
you turn and run away? These are "Fight or
Flight" responses. In these types of situations,
your sympathetic nervous system is called into
action - it uses energy - your blood pressure
increases, your heart beats faster, and digestion
slows down.
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The Parasympathetic Nervous System
It is a nice, sunny day...you are taking a nice
walk in the park. This time, however, you
decide to relax in comfortable chair that you
have brought along. This calls for "Rest and
Digest" responses. Now is the time for the
parasympathetic nervous to work to save energy -
your blood pressure decreases, your heart beats
slower, and digestion can start.
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The Endocrine System

• The endocrine system helps regulate and maintain
  various body functions by synthesizing (making)
  and releasing hormones, chemical messengers.
• The endocrine system is composed of glands that
  release their hormones directly into the
  bloodstream for chemical signaling of target
  cells.
• These glands include the pituitary gland, the
  pineal gland, the hypothalamus, the thyroid
  gland, the parathyroid glands, the thymus, the
  adrenal glands, the ovaries (in females) or
  testes (in males), and the pancreas.
• Hormones alter the metabolism of target organs by
  increasing or decreasing their activity. These
  changes in activity are strictly balanced to
  maintain homeostasis (a stable internal
  environment).

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The endocrine system and the nervous system are
closely associated. Neural control centers in the
brain control endocrine glands. The main neural
control center is the hypothalamus, also known as
the "master switchboard." Suspended from the
hypothalamus by a thin stalk is the pituitary
gland. The hypothalamus sends messages to the
pituitary gland the pituitary gland, in turn,
releases hormones that regulate body functions.
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The Genetic Basis of Behaviour

• Genetics the study of the genetic make up of
  organisms and how this influences physical and
  behavioural characteristics.
• Inherit - to have by genetic transmission
• Heritable - that which may be inherited
• Heredity - is the traits, tendencies
  characteristics inherited from a persons
  biological parents and their ancestors.

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• Genes - bits of DNA (deoxyribonucleic acid)
  which make up a chromosome, they direct the
  production of proteins.
• Note - there are no genes for behaviour as
  such. This is because the main function of genes
  is to make proteins.
•  

Gene causes proteins to be produced.
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• Chromosomes made up from genes (bits of DNA),
  46 in the normal human, 23 pairs, one
  chromosome in each pair coming from each parent.
  Thus each chromosome contains pair of genes, one
  gene in each pair coming from each biological
  parent.

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Recessive and Dominant genes-

• Dominant genes control the expression of a
  physical or behavioural characteristic when there
  is a dominant recessive gene in the gene pair,
  or two dominant genes.
• Recessive genes - only control the expression of
  a physical or behavioural characteristic when
  there are two recessive genes in the gene pair.
• See eye colour example in handout

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• Genotype - the actual genetic make up of a
  person as represented in 23 pairs of chromosomes.
  Each person, with the exception of identical
  twins has a unique genotype. E.g. Bb
• Phenotype - the actual expression of a persons
  genetic make up - their physical appearance,
  behavioural characteristics and psychological
  characteristics that result from heredity.
• E.g. Blue or non-blue eyes
• Environmental factors intervene between genotype
  and phenotype, thus identical twins who share the
  same genotypes may exhibit different phenotypes.

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A dramatic example of the way environmental
factors can intervene between genotype and
phenotype is seen in people with PKU.   PKU
phenylketonurea - a genetic disorder that
prevents the metabolism of an amine
phenylanaline. The gene responsible for PKU is a
recessive gene (pp genotype). Phenylanaline
is a toxin and destroys the nervous system in
children, thus the child ends up with brain
damage and intellectual impairment(phenotype).
If the condition is diagnosed at birth and the
baby is given a special diet, free of
phenylanaline, the child will grow and develop
normally (alternative phenotype).  
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The intervention between genotype phenotype
highlights the nature nurture debate in
psychology and suggests that neither one on its
own is sufficient to explain human behaviour.
It is therefore important to study the
interaction between genetic environmental
factors especially for psychological
characteristics such as anxiety eating
disorders.
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Investigating the genetic basis of behaviour.

• Heritability the proportion of the total
  variability of a trait in a given population that
  is attributable to genetic differences among
  individuals within the population.
• Heritability coefficient - a numerical
  expression of the extent to which a behaviour or
  characteristic is determined by heredity.
  Coefficient varies between 1.0 and 0.
• e.g. A coefficient of 1 characteristic
  determined solely by heredity and a coefficient
  of 0.5 50 heredity 50 from the environment.
  Where there is no natural variability in a trait
  (e.g. humans all have two arms) the coefficient
  is 0.

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• Ideally, the way to investigate heritability
  would be to manipulate either the environment or
  the genetic make up of individuals until the
  exact contribution of each could be determined.
  However this is not possible.
• So, what methods are used?
• selective breeding in animals
• naturally occurring phenomena
• twin studies - Twin studies look for similarity
  (concordance) between twins for particular
  characteristics traits.
• adoption studies - Adoption studies compare a
  trait or characteristic between adopted children
  and their adoptive parents and the biological
  children and their biological parents.

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Examples of these studies-

• Selective breeding in animals
• Robert Tyron 1940
• Aim use selective breeding to see if genetics
  influenced the ability of rats to learn to run
  through a maze.
• Method large number of rats trained to run
  through a maze number of errors made was
  recorded. The rats that learned to run the maze
  the quickest and those that learned the slowest
  were selected. A selective breeding programme
  over several generations was carried out on the
  two groups and the speed of learning to run the
  maze of each generation was recorded.

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• Results - the bright rats ran the maze faster
  and mad fewer mistakes than the dull rats at
  each generation.
• Conclusion Maze learning in rats can be
  manipulated through selective breeding and the
  ability to learn to runa maze is influenced by
  genetics, that is it is an heritable
  characteristic.

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• Twin Studies
• Gottesman Bertelsen (1989)
• Aim to see if people who inherit a
  predisposition to develop schizophrenia will
  always develop it.
• Method twin study looked at the incidence of
  schizophrenia in children of discordant
  monozygotic and dizygotic twins. (discordant
  one twin ahd schizophrenia and one did not).
• Results
• 17 incident of schizophrenia in children of
  discordant monozygotic twins.
• For children of dizygotic twins, 17 incidence if
  the parent twin had schizophrenia but only 2 if
  the parent twin did not have schizophrenia.

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• Conclusion schizophrenia is heritable (so
  people may inherit a predisposition to develop
  it) but this does not mean that someone will will
  definitely go on to develop it.
• NOTE- Schizophrenia a mental disorder
  characterised by hallucinations, delusions,
  thought disturbance and emotional social
  withdrawal. Typical onset in late teens/early
  twenties, affects just under 1 of population.
  1/3 will recover, will improve, will not recover.
• Most widely accepted theory of schizophrenia is
  that people have a genetic predisposition to
  develop it but this is only triggered off by
  stressful environmental experiences
  (Diathesis-stress theory).

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• Adoption Studies
• Scarr Weinberg (1978)
• Aim to see if genetics plays a role in the
  development of intellectual abilities.
• Method Used a standardised intelligence test
  (WAIS) with parents and their adoptive
  biological children. Compared the scores of the
  parents with the children using correlation.
• Results Correlations were higher between
  parents and their biological children than
  between parents and their adoptive children.
• Conclusion since the children were raised in
  the same environment, this suggests that genetics
  play a significant role in determining
  intellectual abilities.

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Evaluation of the Biological Approach

• Positive Contributions
• Very scientific approach. Uses empirical methods
  of research. (In contrast to the humanistic
  psychodynamic approaches)
• Offers strong counter arguments to the nurture
  side of the nature - nurture debate. (In contrast
  to the behaviourist approach)

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• Has contributed to an understanding of many areas
  of human behaviour e.g. of areas you will study
  in Y13
• Gender development e.g. influence of hormones
  and genetics on gender identity and development
  (Remember the Bruce Reimer case study?)
• Abnormality Genetic influences in anxiety
  disorders, serotonin level involvement in bulimia
  nervosa.
• Stress e.g the roles of the sympathetic nervous
  system endocrine system.

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• The practical applications e.g. drug therapy to
  treat mental disorders are usually very
  effective. (look out for the use of drugs in
  treating anxiety disorders in Y13)
• Many other practical applications e.g. stress
  management (look out for Biofeedback in Y13),
  arousal in sport, in industry (effects of jet lag
  on performance).

93
Criticisms

• REDUCTIONISM
• the reduction of complex human psychological
  physical processes to very simple processes
  looses sight of the person as a whole fails to
  reflect the complexity of human interaction and
  experience. (Stress taking a biological
  approach fails to take into account individual
  differences in the appraisal of stressors)

94

• NEGLECT OF ENVIRONMENTAL FACTORS
• - its emphasis on the nature debate tends to
  ignore the very important environmental factors
  that influence human behaviour, in particular
  social context. ( e.g. Eating disorders fails
  to account for why one identical twin has an
  eating disorder and the other doesnt
  environment must have played a part).

95

• THE MIND-BODY DEBATE
• - it largely ignores this debate offering no
  explanation of how the mind and body (mental
  physical) interact to produce the whole person.

96

• OVER SIMPLISTIC
• biopsychological theories often over simplify
  the huge complexity of physical systems and their
  interaction with the environment (e.g. stress
  interactional model)

97

• ETHICAL ISSUES
• the main ethical issues revolve around the work
  on genetics. The Human Genome Project aims to map
  out the entire genetic make up of people. This
  has potential for genetic manipulation, selective
  breeding and cloning. Tampering with human
  genetic make up may have some benefits but some
  scientists may be unethical in their uses of
  these scientific discoveries.