1. The Biology of Behaviour
• To an extend the bodies behaviour is controlled by a central organ (brain)
• The brain has a primitive part that focuses on keeping us alive but also has a part
that is more modern trying to help us with success
The Brain and its components
• Action potential- basic ways messages are sent in the brain
• Electrical currents cause the animations of the brain
• But its actually more electrochemical
• Central nervous system- brain and spinal cord
• Peripheral nervous systems- nerves
• Reflexive behaviour are not very thought out- example quick reflex of escaping
heat and being burned or any form of escaping pain.
• Brain Stem, Cerebellum, and the different hemispheres.
• The brain is a critical organ and that’s why it is protected by the skull.
• The brain has no pain sensors, therefore you can not feel any sensation when it
• Meninges – protect the brain, similar to the pads in a football helmet
• Knockouts- brain shuts down due to the brain coming into contact with the skull
• White matter inside brain is mainly for structure in the brain
• Brain matter is where the complex neural signals are sent and the complex brain
process is done
• Due to the folds and fishers of the brain you can get more surface area and more
brain matter into a smaller spot
• The peripheral nervous system takes commands from the central nervous system
and delivers them throughout the body such as moving your hand or walking.
• Somatic nervous system- controls the goal driven or will driven commands
• Autonomic Nervous Systems- controls the automatic commands- also controls
the organs and the general working condition of the body
• Two parts to the Autonomic system- sympathetic and parasympathetic
• Parasympathetic is when your body is relaxed, heart rate is normal blood
pressure is normal
• Sympathetic is when your respiration increases, your heart beats faster, pumps
blood to muscle, prepares your body for action
• 4 F’s of the sympathetic mode- Feeding, fighting, fleeing and Fucking
• Sympathetic nervous system kicks in involuntarily , and is very automatic, and
• Same as the Parasympathetic mode, you cant just calm yourself right down
• That is why they both fall under the Autonomic System
• Both the ANS and SNS send muscles and battle for command of the body, and
usually the SNS will win because it is the controlled system
Cells of the Nervous System
• Nerve cells- long chain of cells to pass signals from brain to muscle
• Passed along thanks to chemicals
• Large bulbous end (soma) that had numerous tree like structures (dendrites)
coming out of it,
• Two nerve cells don’t actually attach, they come very close but are separated by
synapses. One side sends out chemicals and the other one has receptors that
read what its saying
• Fire- nerve cell sending its signals to others.
• When a nerve cell decides to fire there are these little channels, so in order to
send a signal little gates open up which allows energy to flow, causing another
gate to open, and so on all the way down.
• Myelin Sheathes insulated these processes so that the firing of one axon doesn’t
affect the firing of another.
• Not enough myelin on the axons causes cystic fibrosis.
• Why do chemicals have such an effect on our brains?
• Neurotransmitters of neuromodulators- transmit neuron signals
• Not that many neurotransmitters- probably only 5
• Drugs can act as neurotransmitters and affect the whole brain
• Examples of drugs affecting brain is side effects in medicinal drugs. Viagra may
Study of the Brain
• Most research on brains comes from animal research
• This was because you can make animals act as if they had certain diseases.
• Researchers come up with animal models- things you can do that results in
• Doing research on animals saves humans from the failed trials.
Measurement and Stimulations
• When are area of the brain is more active you can hear more snapping and
• Contra laterally- the left side of your brain deals with the right side of your body
and vice versa
• Phantom limb pain- when a limb is lost but you can still feel as if its there.
• Pleasure centre- something that feels so good that a person or animal will do it
until they died for example Heroin.
• Self stimulation study- review
• over the last few decades technology has advanced so that now we can look at
the human brains in a way that is not invasive.
• CT scans are becoming less useful because of other ways of scanning areas of the
• MRI does the same thing as a CT scan but better and clearer
• MRI can give you a computer based 3D picture of the brain
• The brain may and may not be act like a muscle, it doesn’t get bigger with work,
but as its depleted form work more blood flows, similar to muscles
• PET scan allows you to follow the blood flow
• FMRI- Functional magnetic resonance imaging- mixture of MRI and PET scans-
newest type of scan.
• Can see where the bloods going and on a 3D model
Methods that parallel animal work