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1. Examine one study related to LOF in the brain
2. Explain, using one or more examples, the effects
of neurotransmission of human behaviour
Aphashia
 Loss of ability to understand or express speech,
caused by brain damage.
Broca’s Aphasia

Paul Broca (1824-1880)

Damage to a specific part of the brain was responsible for the loss
of ability to produce coherent speech.

Severe articulation delay

Sarah Scott Youtube

Broca (1861) found that people suffering from damage in an area
(that was eventually called the Broca’s area) were unable to
understand and make grammatically complex sentences. Their
speech consists of almost entirely content words.

Patients have a difficult time producing speech but could
understand it.
Wernicke’s Aphasia
 (1874) – First described the area that appears to be
crucial for language comprehension. People who
suffer from damage to Wernicke’s area are unable to
understand content words while listening, and they are
unable to produce meaningful sentences.
 Patients could produce speech, but not understand it.
Your Turn…
 You already have the outline for the SAQ prompt (2.2
handout). Apply the same outline to a different study. The
following could be used on your exam:

Broca (Tan)

Sperry

Gazzainga

Phineas Gage

Ogden (2005) – Janet

Wernicke
1.
Explain the study (Aim, Method, Results/Findings)
2.
What can be learned about LOF from the study?
3.
Evaluation of the study
Natural Experiment or
Case Study?
 Sperry’s work is sometimes considered a natural
experiment, although others argue it is a case study.
 Corpus Callosum is a part of the brain that joins the
two hemispheres and it appears to be responsible for
communication between them.
 What do you think?
 Can the findings be generalized to the rest of the
human population? Explain.
Physiology & Behaviour:
Neurotransmission
 Neuron Transmission
How do nerve cells communicate?
 There are 3 main parts to the transmission process at the
synapse

1. Neurotransmitters are stored in vesicles inside the
terminal button of the axon; the vesicles are transported to
the edge of the button and the neurotransmitters are released
into the synaptic gap

2. In the synapse, neurotransmitters can bind with a receptor
site on the next neuron if they fit (lock & key). If enough of
the NT binds to the receiving neuron’s receptor sites, the
neuron will ‘fire’ (meaning it will transmit the info across its
cell body electronically)

3. Any unused NT’s are reabsorbed back into the neuron of
origin (REUPTAKE….RECYCLED to be used again)
The transmission process can be
altered by drugs when:
 1. Certain drugs introduced to the nervous system can
encourage or prevent the production and release of NT’s,
thus, increasing or decreasing the amount of NT’s available
in the synapse.
 2. Certain drugs can occupy receptor sites that would
normally receive a neurotransmitter. When a drug does
this, it has its own effect on the receiving neuron as well as
preventing the naturally occurring NT from from
completing the transfer.
 3. Certain drugs can prevent the reuptake of NT’s which
allows them more time so bind to receiving neurons.
Caffeine…
 Caffeine follows rule #2. When a person begins to feel
sleepy, a neurotransmitter called ADENOSINE is being
released into the synaptic gap in a specific part of the brain.
 Adenosine acts to inhibits activity and prepare the body for
sleep.
 When caffeine enters the synaptic gap, it binds with the
receptor sites that adenosine normally uses, and prevents
the normal inhibition of activity.
 In addition, caffeine actually stimulates brain activity,
which means that a person’s movements and thoughts may
become faster
Drugs & Behaviour
 Our body easily develops tolerance to drugs
(adaptability) requiring higher doses to achieve the
same effect as the brain compensates for the drug use
 Once the effects of the drug wears off, the symptoms
of withdrawal occur in force and the effect you were
blocking by taking the drug takes hold.
 Much drug research has been done through
experimentation with animals and humans.
Dopamine Levels
 Neurotransmitter involved in a goal-directed
behaviour (motivation) such as pleasure-seeking,
control of movement, emotional response and
addictive behaviour
 Released into the brain’s reward system
 High levels of Dopamine have been associated with
Schizophrenia
 Low levels of Dopamine have been associated with
Parkinson’s Disease
Dopamine
 L-Dopa was a breakthrough in treatment for
Parkinson’s Disease ( a degenerative condition that
usually involves a resting tremor, a difficulty initiating
movement, and difficulty in controlling directed
movement such as picking up a spoon or cup).
 Drug was designed to relieve the symptoms by
increasing the amount of dopamine available would
have a positive effect.
Dopamine & Addictive Behaviour
 Dopamine released in the brains reward system and
associated with pleasure seeking and addiction
 Addictive drugs increase amount of dopamine in
reward system
 Can be released by environmental triggers b/c of
association with pleasure
 Nicotine increases levels of dopamine in the reward
circuit, creating feelings of pleasure/relaxation
Serotonin Levels
 Prozac was founded to be effective in reducing symptoms
of depression, theoretically because depression is
associated with low levels of serotonin in specific regions
of the brain responsible for mood regulation.
 Prozac’s action of blocking serotonin reuptake is able to
increase the amount of serotonin available and therefore
facilitate the transmission of mood regulation messages in
the brain.
 How does LSD work? It works against serotonin activity
by blocking serotonin receptors. It seems that one of the
main functions of serotonin is to inhibit dreaming while we
are not sleeping.
Serotonin and Depression
 Delgado & Moreno (2000)
 Correlational Study
 Found lower levels of noradrenaline (norepinephrine)
and serotonin in patients with major depression
 Indicates there is a relationship between
neurotransmitter levels and depression but does not
demonstrate cause-effect relationship
Acetylcholine (ACh)
 ACh is a neurotransmitter linked to synaptic to
synaptic plasticity in the hippocampus
 Plays an important role in learning and STM via the
cholinergic system
 Cholinergic system is a system of nerve cells using
ACh in transmitting nerve signals
 Memory processing / higher cognitive functions
depend on cholinergic system