PSYB32H3 Lecture Notes - Lecture 2: Fluoxetine, Methylphenidate, Sertraline
PSYB32 - Abnormal Psychology/Intro to Clinical Psychology
Lecture 2 - Current Paradigms | Integrative Approaches
The Role of Paradigms
● Paradigm
○ Conceptual framework or approach within which a scientist works
○ Set of basic assumptions
■ Fundamental knowledge on how to solve a problem
○ Implications for diagnosis, treatment and society
○ What is fact, what is bias, and what is political correctness
Biological Paradigm
● Behaviour genetics
○ Genotype vs. phenotype
■ Genotype - unobservable genetic constitution that is fixed at birth but not
static and switch off and on at specific times
● Made up of genetic codes
● Comes 50% from your mom and 50% from your dad
● Fixed
■ Phenotype - totality of his or her observable behavioural characteristics
that is the product of an interaction between the genotype and the
environment
● Hair colour, skin colour
● Dynamic - your genes and the environment are involved
○ Family method
■ Type of method to understand predisposition of certain disorders
○ Twin method
■ Monozygotic (MZ) twins
● Identical twins, come from one egg
● Share 100% of their genetic makeup
● Schizophrenia - only 50% of the twins will develop the disorder
because the phenotype is not automatically determined by the
genotype
■ Dizygotic (DZ) twins
● Fraternal twins
○ Adoptees method
■ Investigates similarities between the adoptee and their biological and
adoptive parents
● Based on the medical model/disease model
● Is there a biological component to a disorder?
● Predisposition - something in our genetic code that you are in a greater risk for
presenting or developing a certain disorder
Biochemistry
● Neurotransmission and its function
○ Neurotransmitters are chemical messengers that allows signals to cross
synapses to transmit information from a nerve cell or neuron to a target cell
○ Coordinate behaviour by stimulating an action or inhibiting an impulse
○ Dopamine functions as both an inhibitory and excitatory neurotransmitter and is
critical for memory and motor skills
■ Plays a role in behaviour, learning, sleep, mood, focus, attention, immune
health and pleasurable reward
○ Gabba, the major inhibitory neurotransmitter widely distributed through the brain
■ Considered a significant mood modulator
■ When gaba levels are too low or gaba action is impaired, neurons can
become over excited which can lead to restlessness, anxiety, and
irritability
○ Glutamate, most common neurotransmitter in the central nervous system
■ Involved in most aspects of brain functioning including cognition, learning
and memory
■ Major mediator of the excitatory signals regulating the brain development
as well as the elimination and formation of nerve synapses
○ Serotonin, present in the brain and digestive tract
■ Important factor in mood, depression, anxiety, sleep, emotions and, the
regulation of appetite and temperature
○ Acetylcholine (ACH)
■ Triggers voluntary muscle, contractions, controls heartbeat and,
stimulates the excretion of certain hormones
■ Critical for sleep, attentiveness, sexuality, and memory
○ Norepinephrine (noradrenaline)
■ Acts as a neuromodulator optimizing brain performance
■ As part of the body’s fight or flight response norepinephrine quickly
provides an accurate assessment of danger of stressful situations
■ Excessive amounts of this chemical can leave you anxious and
hyperactive
○ Epinephrine (adrenaline)
■ Both a neurotransmitter and a hormone that is essential to metabolism,
attention, mental focus, and our innate response to stress, fear, anger,
panic or excitement
■ Abnormal levels are linked to sleep disorders, anxiety, hypertension and
lowered immunity
● Reuptake in the context of depression and its treatment
○ Biological factors that cause depression
■ Role of neurotransmitters such as serotonin and noradrenaline
○ Low serotonin can lead to sadness, anxiety and worthlessness
○ Synapse - the gap between the presynaptic neuron and the postsynaptic neuron
■ When enough serotonin is received by the postsynaptic neuron the
message can move forward and creates positive effects on an individual's
mood
■ In people who do have depression too little serotonin is available to be
released and received by the postsynaptic neuron which can interfere
with the message being sent and quite often results in symptoms of
depression
○ SSRI’s
■ Block reuptake of serotonin
■ The main effect is to reduce or block the reabsorption or reuptake of
serotonin by the presynaptic neuron
■ The SSRI will travel to the synapse between these neurons and it will bind
itself to the serotonin reuptake transporters on the surface of the
presynaptic neuron and will block the serotonin from being sucked back
up into that presynaptic neuron by doing this serotonin levels within the
synapse will increase leaving more serotonin free to stimulate the on the
postsynaptic neuron and will leave the individual feeling happy and
improving their overall mood
Structure and Function of the Human Brain
● Cortical Brain Surface
Document Summary
Lecture 2 - current paradigms | integrative approaches. Conceptual framework or approach within which a scientist works. Fundamental knowledge on how to solve a problem. What is fact, what is bias, and what is political correctness. Genotype - unobservable genetic constitution that is fixed at birth but not static and switch off and on at specific times. Comes 50% from your mom and 50% from your dad. Phenotype - totality of his or her observable behavioural characteristics that is the product of an interaction between the genotype and the environment. Dynamic - your genes and the environment are involved. Type of method to understand predisposition of certain disorders. Schizophrenia - only 50% of the twins will develop the disorder because the phenotype is not automatically determined by the genotype. Investigates similarities between the adoptee and their biological and adoptive parents.