Transcript STRESS - Beauchamp Psychology

STRESS
Biological Psychology
Miss Bird
Stress and illness
Immune system
Psychiatric conditions
Cardiovascular disorders
Stress and illness is broken down into 3 sections. In the exam if the Q
asks for stress-related illness you can write about any of the 3
sections. However the examiner may be specific and ask for just the
immune system so make sure you read the question carefully.
Stress-related illness: The immune
system
Pollack (1988) - link between stress and illness.
Evans et al (2000) – stress is associated with
dysfunction of the immune system.
Reminder
1.
SAM – damage to lining of the blood
vessels (heart disease - CVDs).
2.
PAS – increased cortisol levels,
suppresses/weakens the immune system.
What is the immune system?
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Main function is to protect the body from
infection.
It consists of a system of cells which fight
against intruders in the body.
It defends the body against bacteria, toxins,
viruses and parasites.
These are known as antigens.
2. If an antigen enters your body, the
immune system attempts to detect
and eliminate it before it stays there
and reproduces.
1. It creates a
barrier that
prevents antigens
from entering your
body.
How does the
immune
system work?
3. If the antigen
starts to
reproduce, the
immune system is
responsible for
destroying it.
Components of the immune system
Thymus
Lymph nodes
Bone marrow
Spleen
Lymphatic tissue
of the intestine
Cells of the immune system
LEUCOCYTES
 White
blood cells.
 Bone marrow.
 Specific type in immune response =
lymphocytes.
 Type T and B cells (thymus and bone)
detect and destroy antigens.
 Natural killer (NK)cells defend against
infection.
Cells of the immune system
ANTIBODIES
A
specific B cell is tuned to a specific
antigen.
 When that antigen is present in the body
the B cell produces millions of specialised
immune proteins to destroy it.
Cells of the immune system
MACROPHAGES
 These
pick up and ingest foreign materials.
 They give antigens to other cells in the
immune system to destroy them (B and T
cells).
Two types of immunity
Th1 immunity
 Fights infection
aggressively.
 Active during the
night.
Th2 immunity
 Second line of
defence.
 Specialised immunity
in form of antigens.
 Active during the
day.
Two types of immunity
 These
responses are counter-regulatory –
one works during the day and one works
during the night.
 When one branch is active it produces
chemicals called cytokines that block the
action of the other branch.
 This ensures that the body has a balance
between the two types of immune response
with Th2 active during the day and Th1
active during the night.
 Stress can influence the balance between
each branch of immunity.
Research into stress and
immune system functioning
 Most
studies of the relationship between stress
and immune system functioning have focused
on acute (short-term) stressors and have found
a decrease in immune cell function.
 However
other research has focused on the
effect of chronic (long-term) stressors and also
found a decrease in immune system
functioning (decrease in white blood cell
functioning).
Independent task
 Read
the 4 studies on stress and
immune system functioning in your
booklet, including the key study by
Kiecolt-Glaser et al (1984).
 Write
down the key points (APFCE) of
each study in the table on your
worksheet.
 You
have 15 minutes.
Independent task
Complete the fill-in-the-gap exercise on
the evaluation into stress and the
immune system.
Use the words provided at the bottom
of the page.
Exam focus (plenary)
 Answer
the past-exam question on stress
and the immune system.
 You have 5 minutes.
 It is worth 4 marks.
 This is to be done in silence.
Assessment
During week 2/3 of the spring term you will
have your first assessment on the stress topic.
This will be a 12-mark essay Q on stress and the
immune system.
12X2 – Friday 16th January P2 single lesson.
12Z1 – Tuesday 20th January P4 single lesson.