wk 8 + 9 BB Flashcards
Nuerodiversity led to a paradigm shift, allowing for
a greater input from the autistic community and collaborative research practices
The social model of disability aligns with neurodiversity as it
it takes social and environmental factors into count
The medical model of disability assumes impairment and tries to
fix the problem
Markers of a universal theory must be
specific (apply to all members of group)
Sensitive (explain all features of the condition)
a universal theory tries to
explain one component that explains differences between groups
Differences in _____ _______ recognition in autistic community
potentially driven by
facial emotion
a subgroup eho performed poorer on a facial emotion recognition task, an who also showed differences in neural processing and clinically defined features of autism
Higher rates of ______ found in autistic people
alexithymia
also associated with higher clinically defined features of autism and increased levels of experienced anxiety
- _____% of the English population diagnosed autistic
0.82
DSM criteria autism
Differences in social communication and interaction
- Specific patterns of behaviour, passionate interests, or focused activities
- Sensory hyper- or hypo-sensitivities
Concordance rates of autism
Twins: MZ rates: 60%, DZ
rates: 5%;
Co-occurring diagnoses
are common in people
with autism across the
lifespan, e.g.:
ADHD (28%)
* Anxiety (20%)
* Depression (11%)
Fact: Most up-to-date
estimate ratio of autistic
males to females is
3:1.
“Girls who meet criteria for
[autism] are at disproportionate
risk of not receiving a clinical
diagnosis.”
Why ?
- Genetic differences and susceptibility
- Underdiagnosis of autistic women and girls
- Differences in characteristics and traits
- Camouflaging
Camouflaging Autistic Traits Questionnaire – CAT-Q
Three subscales:
Masking: strategies used to hide autistic characteristics or portray a non-autistic persona
Compensation: strategies used to actively compensate for difficulties in social situations
Assimilation: Strategies that reflect trying to fit in with others in social situations (the motivation)
which gender camouflages more
females
Theory of Mind:
: the ability to attribute independent mental
states to oneself and others to explain their behaviour
- Evidence for differences in mentalising at the neural level
is
inconsistent
The Double Empathy Problem can lead to
a breakdown in
mutual understanding between autistic and non-autistic
people
levels of acetylcholine are high in the
hippocampus and neocortex
acetylcholine role in sleep
where is this produced to cause this effect
activating AcH neurones in the basal forebrain causes wakefulness
i AcH high or low in slow wave sleep
low
Norepinephrine/Noradrenaline
Activity of noradrenergic locus coeruleus- neurons increases ______
vigilance
Norepinephrine increases or decreases during wakefulness
increases
how is serotonin involved in arousal.
how do concentrations change during sleep/wake cycle
serotonergic neurons are most active during waking, steadily decline during sleep to almost zero acivity in REM sleep.
The second after REM sleep, become very active
Stimulation of raphe nuclei (where most serotonergic neurons are found) causes
locomotion and cortical arousal
histaminergic neurons are located in the
hypothalamus
Drugs that prevent the synthesis of histamine or block histamine receptors do ….
decrease waking,increase sleep
activity in histaminergic neurons is high or low during slow wave and REM sleep
low
cells that secrete Orexin are located in the
hypothalamus
Orexin has a _____ effect in the _____ ______ and all other regions involved in arousal and wakefullness
excitatory
cerebral cortex
Activating neurons in the _____ ______ of mice awakens the animals from REM and non-REM sleep
lateral hypothalamus
does orexin fire more in sleep or awake
more in awake
alpha brain activity
regular, medium frequency waves 8-12 Hz (resting quietly)
beta brain activity
irregular, mostly low amplitude waves
13 - 30 hz (alert and attentive)
Stage 1 sleep d
drowsy
Theta activity (3.5 - 7.5 Hz)
ab 10 mins
Stage 2 sleep
2 characteristics specific to stage 2 sleep
irregular EEG
Theta activity
sleep spindles - short bursts of waves 12-14 hz
K complexes - sudden sharp waveforms
K complexes are associated with
consolidation of memories
increased number of sleep spindles are associated with
higher scores on intelligence tests
stage 3 and 4 , slow wave sleep
high amplitude delta waves . slower than 3.5 Hz
slow wave oscillations
slow wave oscillations have 2 states
down state = inhibition in cortex. neurons in neocortex are silent. suggesting rest
up state = period of excitation where neurons briefly fire at a high rate
REM sleep
EEG desynchrony rapid irregular waves
- paralysis
- if woken, will be attentive and alert
- cerebral blood flow and oxygen consumption accelerated
- body temperature not regulated
sleep is controlled by 3 factors
homeostatic, allostatic, circadian
primary homeostatic process of sleep
presence or absence of adenosine
allostatic control of sleep is mediated by
hormonal and neural responses to stressful situations
to promote sleep, what neurons become active and where
group of GABAnergic neurons in the ventrolateral preoptic area (vlPOA) becomes active and suppresses activity of arousal neurons
the sleep-wake flip-flop is ON when
the sleep promoting neurons in the vlPOA are inhibited and the arousal neurons are active
= awake
Morivation to stay awake is held by which NT
Orexin
orexinergic neurons in the LH hold the flip-flop on, keeping you awake.
If you lose the motivation to stay awake, will be lack of orexin and flip flop will switch off
What factors control the activity of the orexinergic neurons ?
- biological clock
- hunger signals (stay awake)
- satiety inhibit (so sleep)
- build up of adenosine (happens as we are awake) inhibits input from vlPOA to Orexinergic neurons
Acetylcholinergic neurons fire at a ____ rate in REM sleep
high
There is an REM sleep flip-flop
REM-ON neurons are located in the _____
REM-OFF neurons are located in the_____
pons (in SLD)
midbrain (in vlPAG)
During waking the REM -OFF region receives exitatory input from
orexinergic neurons of the LH, tips REM flip-flop into OFF state
how do specific neurons control the muscular paralysis of REM sleep
when the REM flip-flop is on the ON state, motor neurons in the spinal chord become inhibited and cannot respond to the signals arising from the motor cortex in the course of a dream.
- Slow-wave sleep deprivation affects
cognitive abilities,
especially sustained attention, but not physical abilities
in slow wave sleep, Cerebral metabolic rate and blood
flow falls by about
75%
Rebound phenomenon, REM sleep
If deprived of REM sleep, you will have more REM sleep in the
next sleep period
Highest proportion of REM sleep occurs during
brain
development.
Why do adults continue to have REM sleep?
Learning- both REM and slow-wave sleep
facilitate learning
Slow-wave sleep and REM sleep
appear to play different roles in the consolidation of memories e.g.
REM sleep facilitates consolidation of non-declarative memories
slow-wave sleep facilitates consolidation of declarative memories
Studies by Peigneaux et al. (2004) and Wamsley et al. (2010)
investigated the role of slow-wave sleep in navigation (learning
your way around a virtual town)
Both studies confirmed a role of slow-wave sleep in learning our
way around.
* We appear to rehearse the information during slow-wave sleep
and consolidate learning.
