CHAPTER TWO – Current Paradigms and the Role of Cultural
Paradigms: Conceptual framework or approach within which a scientist works
How to understand a patient
How to gather data
How to study information presented
The abnormality arises due to some neurological/biological issue. The abnormality is
caused by the body.
Genotype versus phenotype
Genotype: inherited characteristic
Phenotype: Observable, behavioural characteristics. Product of the genotype and
o A disorder is not inherited by genetics. You can have the gene that makes
you predisposed for having it.
If a predisposition can be inherited, a study of the family should show a
relationship with the index case (the individual with the disorder) and the probans
o Very true with schizophrenia
Monozygotic (MZ) twins – share 100% of genetic makeup
Dizygotic (DZ) twins – share of 50% of genetic makeup
Concordance: When twins are similar diagnostically similar.
o Predisposition shows that the concordance between monozygotic twins
should have a higher rate than dizygotic twins.
o This means the trait is heritable.
Environment can be ruled out through this method
Look for a large collection of people in a family unit who might have a disorder.
Looking for biological/genetic markers of the disorder to try to link up what might
be common for the disorder. Biochemistry
Information between synapses is caused by electricity
Messages are chemicals that are contained by until they are activated by an
Neurotransmitters move from one neuron to the next from one synapse to the
other, moving across a synaptic cleft
o Serotonin: has many functions, limits violent impulses
o Noradrenaline: receives messages about outside threats and prepares the
body to react
o Substance-P: carries messages about pain
o Endorphins: pain killers
If electrical impulses go wrong, the neurotransmitters also go wrong, leading to
When action potential reaches the synaptic terminal of axon, it reaches the
synapse (the area where two neurons meet).
They are split by the synaptic cleft – the first is the presynaptic neuron (axon) and
the receiving neuron is the postsynaptic neuron (dendrite)
The action potential makes the synaptic terminal positively charged, sending
neurotransmitters into the synaptic cleft. The neurotransmitters quickly diffuse
across to the receptors of the dendrite.
Each receptor binds to specific neurotransmitters. The receptors open ion
channels so the ions of the neurotransmitters can diffuse across the cell
membrane of the dendrite.
The diffusion causes a postsynaptic potential. They can be excitatory (EPSP) or
inhibitory (IPSP), the first making a neuron more likely to fire and the second to
make it less likely to fire. A synapse can either be an excitatory synapse or
Postsynaptic potentials cannot last long. They then diffuse back to their synapse.
These potentials travel far enough to reach the cell body where it is decided what
the response will be.
Clinical psychologists don’t spend a lot of time with neurochemistry because they
cannot alter it – they can’t prescribe drugs.
Structure and functions of the brain
Cortical (outside of brain) structures are in charge of higher order thinking. Subcortical (inner parts of brain) structures are more involved in movement disorders.
Frontal lobes – executive functioning (motor movement, planning, inhibition, emotion,
Right side: retrieval of information
o damage to this side can give rise to manic-like states
Left side: oncoding (bringing in information); speech
o damage to this side can give rise to depressed-like states
Temporal lobes – language areas
Right side: comprehension of non-verbal sounds
Left side: Wernicke’s area - comprehension of language sounds
Parietal Lobes – visual/special functioning
Right side: damage to this side may result in visual neglect – ignoring one side of
Left side: damage to this side results in difficulty in understanding movement
Occipital Lobes – vision
How do you investigate the brain? Structuaral neuroimaging techniques
Functional neuroimaging techniques
fMRI is a combination of both
Approaches to treatment
Anxiolytics – used for anxiety disorders; sleep disorders; phobic disorders; pain
o Alprazolam (Xanax); Clonazepam (Klonopin); Diazepam (Valium);
Antidepressants – used for depressive disorders; eating disorders; first-line treatment
for pain disorders; sometimes for demetia
Selective Serotonin Reuptake Inhibitors (SSRIs)
o Celexa; Prozac; Zoloft
o Elavil; Amitryptine
Monoamine Oxidase Inhibitor (MAOIs)
o Nardil; Parnate
Antipsychotics – used for schizophrenia; behavioural disorders;
Second generation antipsychotics
Psycho-Stimulants – works by improving cognition (ability to focus/remember); used for
o Ritalin; Aricept Psychoanalytic paradigms
Sigmund Freud (1856-1939)
Structure of the mind – gave rise to neuroses (abnormality) caused by conflict between
the 3 structures
Id – below the level of the unconscious.
o Pleasure principle –