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Transcript
Click on the topic that you want to go to:
Insomnia
Sleepwalking
Narcolepsy
Insomnia
Click on the section you would like to go to:
Factors
influencing
insomnia
Explanations
of primary
insomnia
Eplanations of
secondary
insomnia
Return to
main menu
Guidance on
evaluating
studies
Guidance on IDA
for primary
insomnia
Guidance on IDA
for secondary
insomnia
General
commentary on
primary insomnia
explanations
Insomnia
Factors influencing insomnia
Click on the section you would like to go to:
Age & gender
Sleep apnoea
Insomnia
Factors influencing insomnia:
Age & Gender:
Older people & women are more likely to
suffer from insomnia
In older people, this may
because of increasing physical
problems such as arthritis or
diabetes
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insomnia menu
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main menu
In women, the greater likelihood of
insomnia may be due to hormonal
fluctuations (e.g.The menopause)
Go to sleep
apnoea
Insomnia
Factors influencing
insomnia:
Sleep Apnoea:
During a bout of apnoea,
carbon dioxide builds up in
the bloodstream to the
point where it stimulates
chemoreceptors (neurons
that detect specific
chemicals in the blood)
These cause the sufferer to
wake up gasping for breath.
Occasional bouts of sleep
apnoea are quite common,
but in some it is a regular
occurance.
Watch
someone
experiencing
sleep apnoea
Return to
insomnia menu
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main menu
Go to age &
gender
This is because the pauses in breathing
that characterise the condition may
occur for up to 50 times an hour, thus
having a major disruptive effect on sleep
Sleep apnoea can also be considered an
explanation of secondary insomnia
Sleep Apnoea
Return to
sleep apnoea
Return to
insomnia menu
Watch clip
again
Why do you think this condition is linked to insomnia?
Insomnia
Explanations for Primary insomnia
Click on the topic you would like to go to:
Personality
Hyperarousal
Insomnia
Explantions for Primary insomnia:
Personality:
Kales et al (1976) found that
insomniacs were more likely to
internalise psychological
disturbance, rather than acting out
problems or being aggressive
How well does this research
support the view that
internalisation causes insomnia?
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insomnia menu
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main menu
The researchers proposed that
internalisation leads to higher
levels of emotional arousal and
increased likelihood of feeling
anxious, which is why it is a risk
factor for insomnia
Guidance on
Go to
evaluating
hyperarousal
studies
Insomnia
Explantions for Primary insomnia:
Hyper-arousal:
It has been suggested that insomniacs
experience a state of hyper-arousal.
Click on the links below for more information. Select two
studies out of the three given to put onto your worksheets
Definition
of hyperarousal
Research
into
hyperarousal
Study 1
Research
into
hyperarousal
Study 2
Research
into
hyperarousal
Study 3
Return to
insomnia menu
Hyper-arousal definition
A majority of patients with insomnia are chronically
hyperaroused and, surprisingly, not only at night. This
means, among other things, that their metabolism is
faster than that of good sleepers, their body
temperature is slightly higher, their brain waves are
faster, and they are thinking and speaking fast, highly
aroused, as if anxious
Return to
hyperarousal
main page
Research into hyper-arousal
Study 1
Vgontzas (2001) found that insomniacs have
increased levels of adrenocorticotropic hormone
(ACTH) and cortisol, both of which are
associated with stress and arousal
Return to
hyperarousal
main page
Go to
study 2
Go to
study 3
Guidance on
evaluating
studies
Research into hyper-arousal
Study 2
Nofzinger et al (2004) found that the transition from
being awake to being asleep is usually associated with a
decrease in activity in the brain stem, thalamus and
prefrontal cortex. Using PET scans, Nolfzinger et al
showed that insomniacs experienced a smaller decline in
such activity when going to sleep. In fact, they found
elevated level of activity in the brains of insomniacs
Return to
hyperarousal
main page
Go to
study 1
Go to
study 3
Guidance on
evaluating
studies
Research into hyper-arousal
Study 3
Winkleman (2008) Insomnia may be caused by specific
changes in brain chemistry. They found that people who
had been suffering with insomnia for more than six
months have reduced levels in their brain of the
neurotransmitter GABA. This is known to reduce levels
of activity in the brain. Therefore, reduced GABA would
lead to an inability to ‘switch off’ at night.
Return to
hyperarousal
main page
Go to
study 1
Go to
study 2
Guidance on
evaluating
studies
Insomnia
Guidance on evaluating studies
When evaluating studies of insomnia think
about the following points:
Return to
insomnia menu
Are method
there anyis
What
are
problems
with
AreWhat
What
there
conclusion
anythe
problems
being
used?
Are is
positive
pointsto
making
with
the
attempting
study
there
any problems
relating
to the
way
generalisations
establish
attempting
a cause
to and
draw?
with
using
this
the
study
was from
from
this
effect
relationship
method?
study?out?
thiscarried
study?
Return to
main menu
Play slide again
Insomnia
Guidance on using IDA to evaluate theories of
primary insomnia
The nature
nurture debate
Reductionism
Some of these explanations are
reductionist
What does that mean?
Are there any consequences
of this (socially sensitive)?
Why does it matter?
What factors have not been taken
into account?
Return to
insomnia menu
Does the explanation fall on
the nature or nurture side of
the argument?
Return to
main menu
Could we explain the
insomnia using the other
side of the argument?
Insomnia
Explanations for secondary insomnia
Click on the topic you would like to go to:
Medical
conditions
or
First watch a brief
case study of
secondary insomnia
Mental Health
Insomnia
Return to
secondary
insomnia
Return to
insomnia menu
Watch clip
again
What are the factors that seem to be responsible for this
woman’s insomnia?
Insomnia
Explanations for secondary insomnia
Medical conditions:
A range of medical conditions have been shown to be
associated with insomnia
Research into medical conditions and insomnia
Katz et al (2002) conducted a study involving 3,445 patients with a
diagnosis of one or more of five chronic medical conditions,
including hypertension, congestive heart failure. Responses to
self-administered questionnaires showed that 50% of them
reported syptoms indicative of insomnia, such as difficulty
initiating and maintaining sleep. Insomnia was rated mild in 34%
of the patients and severe in 16%
Return to
insomnia menu
Return to main
menu
Go to mental
health
Guidance on
evaluating
studies
Insomnia
Explanations for secondary insomnia
Mental health:
There is evidence to suggest that insomnia is an
additional symptom for many people suffering
with mental health difficulties
Add the details of the following pieces of
research to you worksheets:
Research
into
secondary
insomnia
Study 1
Research
into
secondary
insomnia
Study 2
Research
into
secondary
insomnia
Study 3
Return to
insomnia menu
Insomnia
Explanations for secondary insomnia
Mental health research study 1:
Weiss et al (1962)
What do you think Weiss found? Click
on the button to find out: Results
Percentage
of people
reporting
sleep
disturbance
72%
Go to
Research
Study 2
Go to
Research
Study 3
Guidance on
evaluating
studies
18%
Control
group
Return to
insomnia
menu
Psychiatric
patients
Insomnia
Explanations for secondary insomnia
Mental health research study 1:
Weiss et al (1962)
What do you think Weiss found? Click
on the button to find out: Results
Percentage
of people
reporting
sleep
disturbance
72%
Go to
Research
Study 2
Go to
Research
Study 3
Guidance on
evaluating
studies
18%
Control
group
Return to
insomnia
menu
Psychiatric
patients
Insomnia
Explanations for secondary insomnia
Mental health research study 2:
Ohayon & Roth (2003)
Interviewed 14,195 participants representative of
the general populations of the UK, Italy, Portugal
and Germany over the telephone about their
psychiatric history and their sleep patterns
What do you think they found? Click on the button
to find out: Results
People with insomnia were
six times more likely to
report a mental health
problem, such as depression
or anxiety, than people
without insomnia
Return to
insomnia
menu
Go to
Research
Study 1
Go to
Research
Study 3
Guidance on
evaluating
studies
Insomnia
Explanations for secondary insomnia
Mental health research study 2:
Ohayon & Roth (2003)
Interviewed 14,195 participants representative of
the general populations of the UK, Italy, Portugal
and Germany over the telephone about their
psychiatric history and their sleep patterns
What do you think they found? Click on the button
to find out: Results
People with insomnia were
six times more likely to
report a mental health
problem, such as depression
or anxiety, than people
without insomnia
Return to
insomnia
menu
Go to
Research
Study 1
Go to
Research
Study 3
Guidance on
evaluating
studies
Insomnia
Explanations for secondary insomnia
Mental health research study 3:
Serretti et al (2003) Found that insomniacs and
Depressives may have similar abnormalities in their
biological clocks. Patients with depression who have
been found to have an abnormality in the genes that
govern circadian pacemakers are more likely to
experience severe insomnia
Why does this study maybe
challenge the view that
insomnia is caused by
secondary factors?
Return to
insomnia
menu
Go to
Research
Study 1
Go to
Research
Study 2
Guidance on
evaluating
studies
Insomnia
Guidance on using IDA to evaluate theories of
secondary insomnia
The nature
nurture debate
Approaches
Which approaches are used in
this explanation?
What might that lead to?
Are there any consequences
of this (socially sensitive)?
Why does it matter?
What factors may not been taken
into account?
Return to
insomnia menu
Does the explanation fall on
the nature or nurture side of
the argument?
Return to
main menu
Could we explain the
insomnia using the other
side of the argument?
Insomnia
General commentary on explanations of
primary insomnia:
When discussing explanations of primary insomnia, we need to
understand the interaction between predisposing,
precipitating and perpetuating factors
Click on the section you would like to go to:
Predisposing
factors
Precipitating
factors
Perpetuating
factors
Return to
insomnia menu
Insomnia
Predisposing factors
These are factors that make it more likely that a
person will develop insomnia and include having a
genetic predisposition towards insomnia
In a twin study, Watson et al
(2006) found that 50% of the
variance in the risk for
insomnia could be attributed
to genetic factors
Precipitating
factors
Perpetuating
factors
Guidance on
evaluating
studies
Return to
insomnia menu
Insomnia
Precipitating factors
It is unlikely that predisposing factors alone can explain
chronic primary insomnia. It is likely that precipitating
factors play a part
These include factors such as
environmental stressors or change,
which may trigger insomnia in
those who are vulnerable
Which IDA point does this link to?
Predisposing
factors
Perpetuating
factors
Return to
insomnia menu
Insomnia
Perpetuating factors
Perpetuating factors are factors which maintain the insomnia
even when the original causes have disappeared
These include being
tense about going to
bed because of
previous experience
of insomnia, or simply
the expectation that
sleep will be difficult
Predisposing
factors
Precipitating
factors
I’m
I’m
I don’t
not
going
going
feel
to
Maybe I should
feel
to be
lousy
tired
able
again
to
try counting
get
tomorrow
to sleep
sheep
three
two
one
Damn!
Return to
insomnia menu
Sleepwalking
Click on the section you would like to go to:
Explanation of
sleepwalking:
incomplete
arousal
Explanation of
sleepwalking:
genetics
Explanation of
sleepwalking:
stress-diathesis
Guidance on
evaluating studies
of sleepwalking
Guidance on
using IDA for
sleepwalking
Return to main
menu
Sleepwalking
Explanations:
Incomplete arousal
Sleepwalking is a disorder of
arousal
EEG recordings show a mixture of
delta waves which are characteristic
of SWS sleep, but also higher
frequency beta waves which are
characteristic of an awake state
Click on the links to remind yourself
what the different brain waves look like:
Awake
Stage 4
sleep
Return to
sleepwalking
menu
It looks as though sleepwalking
occurs when the person is
awakened, but the arousal of the
brain is incomplete
But why does this state of
incomplete arousal occur?
Return to
incomplete arousal
Awake
Awake
Go to stage 4
sleep
High frequency, low amplitude waves
A
1
2
3
4
R
C
Go to awake
Return to
incomplete arousal
Stage 44
Stage
EEG recording consists purely of delta waves
A
1
2
3
4
R
C
Sleepwalking
Explanations: genetics
There is some evidence to suggest that
sleepwalking may be genetically
transmitted
Look at the pieces of evidence to
support the genetic explanation and
add the details to your worksheets:
study 1
Study 2
Study 3
Return to
sleepwalking
menu
Sleepwalking
Explanations: genetics
Return to
sleepwalking
menu
Research study 1:
Bakwin (1970)
What do you think Bakwin found? Click
on the button to find out: Results
Concordance
rate for
sleepwalking
Go to
Research
Study 2
Go to
Research
Study 3
Guidance on
evaluating
studies
MZ twins
(19 pairs)
DZ twins
(14 pairs)
Sleepwalking
Explanations: genetics
Return to
sleepwalking
menu
Research study 1:
Bakwin (1970)
What do you think Bakwin found? Click
on the button to find out: Results
Concordance
rate for
sleepwalking
Go to
Research
Study 2
Go to
Research
Study 3
47%
MZ twins
(19 pairs)
7%
DZ twins
(14 pairs)
Guidance on
evaluating
studies
Sleepwalking
Explanations: genetics
Research study 2:
Lecendreux et al (2003)
What do you think Lecendreux et al
found? Click on the button to find out:
Results
Concordance
rate for
sleepwalking
Return to
sleepwalking
menu
Go to
Research
Study 1
Go to
Research
Study 3
Guidance on
evaluating
studies
MZ twins
DZ twins
Sleepwalking
Explanations: genetics
Research study 2:
Lecendreux et al (2003)
What do you think Lecendreux et al
found? Click on the button to find out:
Results
Concordance
rate for
sleepwalking
Return to
sleepwalking
menu
Go to
Research
Study 1
Go to
Research
Study 3
50%
1015%
MZ twins
DZ twins
Guidance on
evaluating
studies
Sleepwalking
Explanations: genetics
Research study 3:
Bassetti (2002) suggests that the same HLA
gene abnormality that is implicated in
Narcolepsy, may be associated with
sleepwalking. He found that 50% of
sleepwalkers that he tested had a version of
the HLA gene found only in 24% of the nonsleepwalkers
Can you think of any problems with drawing
conclusions from this piece of research?
Return to
sleepwalking
menu
Go to
Research
Study 1
Go to
Research
Study 2
Guidance on
evaluating
studies
Sleepwalking
Explanations: stress-diathesis
This theory suggests that a genetic predisposition towards
sleepwalking will be triggered by external factors
Factors that increase the risk of sleepwalking
Click on the boxes to reveal what they are:
Return to
sleepwalking
menu
Guidance on
using IDA for
theories of
sleepwalking
Hormonal
changes
Hormonal
Stress or other
changes
Sleep
Having
Alcohol
deprivation
a fever
associated
with
associated
psychiatricwith
conditions
menstruation
puberty
Sleepwalking
Guidance on evaluating studies
When evaluating studies of sleepwalking
think about the following points:
Are there any
Are
What
What
there
are
method
any
the
problems
is
problems with
with
positive
being
attempting
used?
points
Are
tois
What
conclusion
making
establish
relating
there
any
ato
cause
problems
the way
and
the
study
generalisations
effect
the
with
study
relationship
usingwas
this
from
attempting
to
draw?
from this
this
carried
method?
study?out?
study?
Return to
sleepwalking
menu
Return to
main menu
Play slide again
Sleepwalking
Guidance on using IDA to evaluate theories of
sleepwalking
The nature
nurture debate
Approaches
Which approaches are used in
this explanation?
If there is more than one, how could
that be considered an advantage?
Are there any consequences
of this (socially sensitive)?
Why does it matter?
Are there any factors that have not
been taken into account?
Return to
sleepwalking menu
Does the explanation fall on
the nature or nurture side of
the argument?
Return to
main menu
Could we explain the
sleepwalking using the other
side of the argument?
Narcolepsy
Click on the section you would like to go to:
Explanations
of narcolepsy:
the role of
hypocretin
Explanations
of narcolepsy:
genetics
Guidance on
evaluating
studies
Guidance on
using IDA for
narcolepsy
Return to
main menu
Narcolepsy
Explanations: The role of hypocretin (Hcrt)
It has been suggested
that narcolepsy is caused
by the loss of cells in the
hypothalamus that
secrete Hcrt
More
information
on hypocretin
Study 1
Study 2
Return to
narcolepsy menu
Go to
study 2
Narcolepsy
This study only shows that cells in
the lateral hypothalamus (LH) are
Explanations:
The role
of Ithypocretin
related to a decline
in Hcrt.
is
not a study of narcolepsy itself.
Research
studywith
1: narcolepsy have a
As humans
more than 80% reduction in CSF
Hcrt, we canet
presume
they will
Gerashchenko
al (2003)
have a reduced number of
cells in the LH
(Hcrt)
Destroyed the cells in the lateral
hypothalamus in rats with a neurotoxin. They
found a relationship between the number of
cells lost and a decline in the levels of Hcrt in
the cerebrospinal fluid (CSF). A 73% decline in
Hcrt neurons resulted in a 50% reduction in
CSF Hcrt
What does the rat have to say about it all?
Click on the rat to see his interpretation
of the study
Guidance on
evaluating
studies
Return to
narcolepsy
menu
Narcolepsy
Explanations: The role of hypocretin
(Hcrt)
Research study 2:
Thannickal et al (2007)
People with Parkinson’s disease show sleep
complaints that strongly resemble narcolepsy.
Parkinson’s is a degenerative brain disorder
which involves the loss of cells in many brain
areas. Thannickal et al conducted a post
mortem analysis of the brains of people who
had suffered Parkinson’s disease and found
that the brains had lost up to 62% of the cells
that contain Hcrt. It is further supported by
other research which has shown reduced
levels of Hcrt in the CSF of people with
Parkinson’s disease
More information on
Parkinson’s disease
Go to
study 1
Guidance on
evaluating
studies
Return to
narcolepsy
menu
Narcolepsy
Explanations: Genetics
Research has indicated that there is a genetic
link in narcolepsy in dogs. It was discovered in
the 1970s that certain breeds of dog appeared
to have an inherited form of narcolepsy.
This led to the establishment of a breeding
colony of narcoleptic dogs and a concerted
effort to find the gene or genes responsible
for the disorder
study 1
study 2
Click on this picture to
see a film of a
narcoleptic dog
Return to
narcolepsy
menu
Narcolepsy
Explanations: Genetics
Research study 1:
Nishino & Mignot (1997)
Narcoleptic Doberman
Pinschers have a
genetic mutation
affecting Hcrt
Click on the statement you
think is correct:
Research has shown that
human narcloleptics also
have a faulty Hcrt gene
But...
Research has shown that
human narcoleptics do not
have a faulty Hcrt gene
Can we
generalise to
humans?
Go to
study 2
Guidance on
evaluating
studies
Return to
narcolepsy
menu
Go to
study 1
Narcolepsy
Guidance on
evaluating
studies
Explanations: Genetics
Research study 2:
Sixteen identical twin pairs with at least one narcoleptic
in each pair were studied. In only four of the pairs did
both twins have the condition
This would
suggest that:
(Click on the
statements you think
are correct)
This is good evidence that
narcolepsy is caused by
genetic factors
It seems likely that a genetic
vulnerability must be combined
with environmental factors to
trigger the disorder
Return to
narcolepsy
menu
This is weak support for a
genetic link in narcolepsy
The research suggests that
genetics are more important
than environment in narcolepsy
It seems highly unlikely that genetics
alone can explain narcolepsy. It is the
exception rather than the rule that
narcolepsy runs in families
Despite the lack of genetic
abnormality in humans, 90% of
narcoleptics have extremely low
levels of Hcrt
Narcolepsy
Guidance on evaluating studies
When evaluating studies of narcolepsy think
about the following points:
Are there any
Are
What
What
there
are
method
any
the
problems
is
problems with
with
positive
being
attempting
used?
points
Are
tois
What
conclusion
making
establish
relating
there
any
ato
cause
problems
the way
and
the
study
generalisations
effect
the
with
study
relationship
usingwas
this
from
attempting
to
draw?
from this
this
carried
method?
study?out?
study?
Return to
narcolepsy
menu
Return to
main menu
Play slide again
Narcolepsy
Guidance on using IDA to evaluate theories of
Narcolepsy
Reductionism
Approaches
Which approach is used in this
explanation?
Which approaches have not been
considered?
Why does it matter?
Are there any factors relating to other
approaches that have not been taken into
account?
Return to
narcolepsy menu
Return to
main menu
Is the explanation
reductionist?
How is it reductionist?
How does the reductionist
nature of the research affect
its ability to explain
narcolepsy?
How could the reductionist
nature of the explanation be
considered socially sensitive?