Transcript How to age-protect your brain

What happens to the brain
and mind as we get older?
Dr Catherine Loveday
“A youth who does not
respect his elders will
achieve nothing when
he grows up”
Confucius
INTRODUCTION
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Why study the ageing
brain?
Increasing no. of people
over the age of 65
Research helps us to
learn more about the
ageing brain so that we
can enhance the quality
of old age
Office for National Statistics
Variations in the effects of
ageing
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Changes in normal ageing
brain not uniform: certain
subsets of cells & areas of
the brain more prone to
age-related damage
Time of onset, extent of
physical alterations &
effect on intellect differ
dramatically from one
person to another
Leland McPhie age 95
SENSORY CHANGES
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Vision:
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Hearing
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Large percentage of people 70 & above, have some hearing
loss, usually at high frequencies
Taste & smell
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Lens becomes less flexible & yellowing of lens
Cataracts, glaucoma, macular degradation
Three-quarters of people over 80 have major difficulties with
smell
Smell more affected than taste but both linked
Taste buds & smell receptors continue to be replaced
throughout life so more resilient
Consequences for mental functioning & can be
misleading
BRAIN CHANGES - vascular
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Changes to the
cardiovascular system:
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Circulation less efficient 
brain less well nourished
and toxins less efficiently
removed
Greater likelihood of
strokes and blood clots
Better cardiovascular
health leads to better
brain health
BRAIN CHANGES – key anatomical
changes
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Overall number of brain neurons
decrease but pattern is not
uniform.
Parts particularly affected
include
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limbic system (learning, memory
and emotion),
frontal lobes (planning, strategy,
working memory)
substantia nigra (movement,
reward, learning)
locus coeruleus (stress, panic,
REM sleep)
BRAIN CHANGES - Neuronal
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Damage to internal architecture
of neurons may occur, e.g.
neurofibrillary tangles
Areas between neurons may also
be affected, e.g. amyloid plaques
Tangles & plaques occur in all
ageing brains but are a particular
marker of Alzheimer’s disease
BUT, not all neuronal changes are destructive…
Neuronal plasticity
Coleman, Flood & Buell (1987)
 Net growth of dendrites in
regions of hippocampus &
cortex - middle age & early
old age
 Regression again in late old
age.
 Postulated that initial
dendritic growth represents
an effort by viable neurons to
cope with the loss of their
age-associated neighbours
BRAIN CHANGES- molecular
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Characterised by increased
numbers of free radicals and
oxidised proteins (N.B. Progeria)
Ironically, proteases (enzymes
responsible for breaking down
oxidised proteins) are
themselves oxidised
Studies in rats have shown that
maze learning is directly related
to numbers of free radicals and
oxidised proteins
COGNITIVE CHANGES
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Behavioural & cognitive changes surprisingly few
Coping strategies may be developed in mid old age strengths focused on & lost abilities compensated
(probably less effective in v old age)
Few people decline on all mental abilities - by 60s,
most people have declined on one or two abilities
(typically those used least throughout their life)
Not all individuals decline; few do so at a steady
pace – tends to be stair-step (typically related to life
events)
So which cognitive functions
are affected by age?
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Usually some reduction in
fluid intelligence (logical
problem solving)
memory (especially recall,
source memory, prospective
memory and working memory)
processing speed (affects
ability to do complex tasks or
those with timed element)
executive functions (e.g.
planning, disinhibition)
Which cognitive functions are
not affected by age?
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Knowledge & wisdom
continue to grow
Crystallised intelligence
remains stable (ability to
apply knowledge & skills)
Vocabulary continues to
grow
Some aspects of memory
are resilient, e.g recognition
memory
Piano – Drum
Egg – Seed
Poem – Statue
Enemy – Friend
How to age-protect your brain (1)
A healthy body means a healthy
brain:
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Physical activity, e.g. walking,
running (physical & psychological
benefits)
Keeping healthy: low incidence of
cardiovascular or other chronic
diseases
Good sensory systems with aids
where necessary
Good diet + antioxidants?
Avoidance of ingestion of agents
that interfere with the nervous
system (e.g. alcohol, tranquilizers)
How to age-protect your brain (2)
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Psychological wellbeing is
just as important (direct
impact on physical health
& cognitive functioning)
Favourable and
stimulating environment
Optimism & flexibility
Minimising major life
changes in late old age
Sleep & relaxation
How to age-protect your brain (3)
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Maximise brain power
Mental activity: “Use it or lose it!”
Use strategies:
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Make important things habitual
Use memory aids & mnemonics
Maximise attention when it
matters
Use all senses
One thing at a time
Allow more time
How do we detect changes in pathology
over and above cognitive changes
associated with ageing?
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Look at overall profile & observe nature & rate of change
Eg Alzheimer’s disease begins with noticeable decline in
remembering event-based information.
Rate of decline & appearance of new cognitive symptoms
can help to distinguish between dementia & mild cognitive
impairment:
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More memory loss; disorientation for time, place & person;
silly errors in action & speech; depression & anxiety;
personality intact
Frontal lobe dementia will present first with personality
changes and executive dysfunction
Diagnosis very important & also important to identify
reversible dementias
Conclusions
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Ageing leads to a range of physiological
changes both in the brain and the senses
This leads to noticeable decline in some
cognitive functions but growth or resilience in
others
Keeping physically & psychologically well will
age-protect the brain and using strategies to
compensate will also help
Sometimes ageing leads to abnormal brain
changes - accurate diagnosis is important