Biopsychology: For Year 2 we will add to this… this is what you need for Year 1
The nervous system and the endocrine system
GHG 114-115
OBB 255-265
You need to be able to describe:
1. The divisions of the nervous system: central and peripheral (somatic and
autonomic).
2. The function of the endocrine system: glands and hormones.
3. The fight or flight response including the role of adrenaline.
Lets recap the Biological Approach
• Assumptions of the Bio Approach:
– All behaviour is at first biological so to fully
understand human behaviour, we must look to
biological structures and processes within the
body, such as G___,
and
the
genes,N_____________
Neurotransmitters
and
N_______
S_________.
the Nervous
System
– understanding B_____
S________
function
Brain Structure
andand
function
can explain our thoughts and behaviour
The nervous system
• Biopsychologists assume that behaviour and
experiences are caused by activity in the
nervous system
• This is a specialised network of cells in the
human body and is our primary internal
communication system
• Two main functions:
1.
2.
To collect, process and respond to information in the
environment
To co-ordinate the working of different organs and cells
Use the handout
to support your
note taking
Human
nervous
system
Peripheral nervous
system (PNS)
Autonomic
nervous system
Somatic nervous
system
Sympathetic
nervous system
Parasympathetic
nervous system
Central nervous
system (CNS)
Brain
Spinal cord
The major sub-divisions of the human nervous
system
Human
nervous
system
Peripheral nervous
system (PNS)
Autonomic
nervous system
Somatic nervous
system
Sympathetic
nervous system
Parasympathetic
nervous system
Central nervous
system (CNS)
Brain
Spinal cord
The major sub-divisions of the human nervous
system
The central nervous system (CNS)
The CNS is made up of the
BRAIN and the SPINAL CORD
The brain is the centre
of all conscious
awareness. Outer
layer, the cerebral
cortex, is highly
developed in humans
Divided in two
hemispheres
The spinal cord
is an extension
of the brain
It is responsible for
reflex actions
The CNS passes
messages to and
from the brain
and connects
nerves to the PNS
The peripheral nervous system (PNS)
The PNS transmits messages
via millions of neurons (nerve
cells), to and from the CNS
(we will look at the messages in more detail nxt
lesson)
The PNS is further subdivided into:
1. the somatic nervous system (SNS)
2. the autonomic nervous system
(ANS)
PNS: 1. The somatic nervous system
This is the part of the PNS that is responsible for
carrying sensory and motor information to and
from the spinal cord
PNS: 2. The autonomic nervous
system (ANS)
This governs vital functions
in the body such as:
• breathing,
• heart rate,
• digestion,
• sexual arousal and
• stress responses
PNS: 2. The two main divisions of the
ANS
The two main divisions of the autonomic
nervous system are:
• The sympathetic nervous system
• The parasympathetic nervous system
Their actions are mostly antagonistic - that is
they usefully work in opposition to each other
The opposing actions of the sympathetic and
the parasympathetic nervous system
Organ
Sympathetic nervous system
Parasympathetic nervous system
Gut
Slows digestion
Increases digestion
Salivary glands Inhibits saliva production
Increases saliva production
Heart
Increases heart rate
Decreases heart rate
Liver
Stimulates glucose production
Stimulates bile production
Bladder
Stimulates urination (relaxes the
Inhibits urination (contracting
bladder)
bladder)
Eye
Dilates pupils
Constricts pupils
Lungs
Dilates bronchi
Constricts bronchi
Generally creates
a physiological
calm
maintains
and
conserves
body
energy and
functions
Generally arouses
the body
prepares
the body
to use
energy
for fight
or flight
Complete “Are you
Sympathetic (or
Parasympathetic)?
The Endocrine System
• The endocrine system is in charge of
body processes that happen slowly,
such as cell growth.
• Faster processes like breathing and
body movement are controlled by
the nervous system.
• However, even though the nervous
system and endocrine system are
separate systems, they often work
together to help the body function
properly.
Use the handout to
support your note taking
These release
adrenalin
directly into
the
bloodstream
which
prepares the
body for fight
or flight by
constricting
blood vessels
in the
stomach.
This inhibits
digestion and
gives you that
sick feeling as
well as
increasing
your heart
rate
This controls
the release of
hormones from
all other
endocrine
glands…an
important
gland!
This facilitates
the release of
the female
hormones –
oestrogen and
progesterone
This facilitates the release of the
male hormones – testosterone
Main hormone
released is
melatonin.
Regulates
arousal,
biological
rhythms and
sleep – wake
cycle
OBB pg 260
Thyroid gland
produces the
hormone thyroxine.
This hormone
affects cells in the
heart (increases
heart rate). It also
affects cells
throughout the
body increasing
metabolic rates
(the chemical
processes taking
place in the cells).
This in turn affects
growth rates
Fight or flight response
• Anxiety and fear are important for survival
because they act as a mechanism to protect
the body against stress and danger
• The sympathetic nervous system controls
what has been called the "Fight or Flight"
phenomenon
– It controls the necessary bodily changes needed
when we are faced with a situation where we may
need to defend ourselves or escape.
Imagine…
• You are walking down a dark street at night by
yourself. Suddenly you hear what you suspect
are footsteps approaching you rapidly.
• What happens?
1. Your sympathetic nervous system kicks in
and in an instant, your body is prepares itself
for either defence or escape.
Endocrine and ANS together…
2. Pituitary gland
releases
adrenocorticotrophic
hormone – ACHT
3. ACHT affects
adrenal glands
causing them to
release adrenaline
into the bloodstream
This partnership then leads to….
Fight or flight?
….enabling the body to take action and protect
itself in dangerous situations,
either by running away FLIGHT or fighting FIGHT
When the ‘threat’ has passed…
• Now imagine that the footsteps belong to a good
friend who catches up to you and offers to walk
you home. You feel relief instantly, but your body
takes longer to adjust.
• In order to return everything to normal, the
parasympathetic nervous system kicks in.
• This system is slow acting, unlike its counterpart,
and may take several minutes or even longer to
get your body back to where it was before the
scare.
• Parasympathetic is like a brake…reducing
activity that the sympathetic caused
– Also know as the rest and digest response
• These two subsystems are at work constantly
shifting your body to more prepared states
and more relaxed states
• Every time a potentially threatening
experience occurs (e.g., someone slams on
their breaks in front of you), your body reacts.
The constant shifting between these two
systems keeps your body ready for your current
situation
There is lots to read about this in your text book… please ensure that you are
able to describe the Fight and flight response. There are also some videos I will
put on the Blog
Summary questions
See handout
• Using an example, explain what is meant by
the fight or flight response
If you hear a noise that makes you jump, your
body immediately diverts blood away from
your stomach to your muscles in order for you
to stay and confront a potential attacker
(fight), or run away (flight)
Summary questions
• Give two actions of the sympathetic nervous
system and two actions of the
parasympathetic nervous system
• Sympathetic nervous system – dilates pupils, inhibits saliva
production, dilates bronchi, speeds up heart rate, inhibits
digestion, stimulates glucose production, inhibits urination
• Parasympathetic nervous system – constricts pupils,
stimulates saliva production, constricts bronchi, slows down
heart rate, stimulates digestion, stimulates bile production,
stimulates urination
Summary questions
• Billy is an A level student. He has been asked by
his teacher to give a short presentation to the
other psychology students in his class. Just before
his presentation, Billy feels his mouth go dry and
he starts to sweat. After the presentation has
ended, Billy feels his breathing slow down and he
begins to feel thirsty.
• Use your knowledge of the autonomic nervous
system to explain Billy’s behaviour before and
after the presentation.
Possible answer
Billy feels stressed about giving a presentation to the
class and this activates sympathetic responses in his
autonomic nervous system. Blood is diverted to the
muscles for energy and as a result, Billy sweats to allow
heat energy to be lost from the surface of the skin. It is
the body’s cooling mechanism. His salivary glands have
inhibited saliva production making his mouth go dry.
Once the presentation is over, Billy’s stress is no longer
present and his parasympathetic nervous system is now
acting to restore his bodily functions to a normal state;
this is why his breathing is slowing down. He feels thirsty
as his previously inhibited saliva production has dried his
mouth out and now he is aware of this and this needs
rectifying
Exam Questions
You should be attempting these questions on a regular basis now… more can be found in your
text books 
1. Outline the role of the central nervous system (4 marks)
2. Identify two divisions of the autonomic nervous system (2
marks)
3. Identify the two components of the central nervous system (2
marks)
4. Outline the role of the somatic nervous system (4 marks
each)
5. Outline the role of the autonomic nervous system (4 marks
each)
6. Using an example, outline the function of the endocrine
system in the human body (4 marks)
• Answer the ‘Check it’ questions on page 115
Homework
Label the diagram of the brain using your text
books… OBB 255-256
Make sure you have key functions of each division
/ part of the brain
Additional materials
Fight or flight response
crash-course-biology
When cuddle hormone turns nasty - Interesting article looking at
hormones!