neuro age related changes

age related muscle weakness

muscle atrophy + impaired communication between the brain and skeletal muscles

by the age of 80 what happens?

the nervous system dec by 40% in volume and size

age neuroanatomical related changes in the brain

- dec overall weight and size of the brain

- dec in 5% of brain volume as we age; inc >70 yo

- dec brain tissue

- narrowing of the gyri and widening of the sulci

narrowing of the gyri and widening of the sulci does what?

- inc ventricle size and subarachnoid space

- inc risk for bleeds

brain bleeds sn/sx

- low BP

- lightheadedness

- change in cognition

- headache

cellular age neuroanatomical related changes

- presence of lipofuscins, neuritic plaques, and neurofibrillary tangles (excess junk)

- dec myelin

- dec blood flow

- axonal loss

- loss of sensory neurons

presence of lipofuscins, neuritic plaques, and neurofibrillary tangles

inc amounts of "junk" associated with dementia and alzheimer's

cellular age neuroanatomical related changes - dec myelin

slower conduction speed and reaction times

- contributes to fall risk

cellular age neuroanatomical related changes - dec blood flow

to nervous tissue

- vascular supply estimated to dec by 10-15%

age related neurochemical changes

- dec synthesis, metabolism, and receptors of major neurotransmitters

- acetylcholine

- dopamine

acetylcholine affects

- memory

- motivation

- arousal

- attention

dopamine affects

- movement

- pleasure

- attention

- mood

- motivation

what neurotransmitter is inc for those with dementia?

acetylcholine via acetylcholinesterase

what neurotransmitter is inc for those with Parkinson's disease?

dopamine

age related neuromuscular changes after the age of 60

denervation and reinnervation of muscle fibers

- fewer and larger surviving motor units

clinical implication of age related neuromuscular changes

contributes to dec in fine motor

role of autonomic system

maintain homeostasis

- via a balance between sympathetic and parasympathetic systems

age related autonomic changes may contribute to what?

- dec gastric motility

- control of blood flow from periphery

- risk for cardiovascular complications

- altered vagal response (vasovagal syncope)

clinical implications of autonomic changes

- slower moving speed, delayed reaction time = falls

- dec strength

- dec coordination

- dec fine motor

- diminished reflexes (postural)

- postural hypotension

- less ability to tolerate stressors

- speed/accuracy trade off

- dec learning and memory

what is common in older adults?

postural hypotension

- common due to changes in sensory neurons

- **diet and exercise help to mitigate these changes

age related vestibular changes

degenerative changes in otoconia, utricle, and saccule

- link between dec calcium and BPPV

- loss of vestibular hair cell receptors

- dec amount of vestibular neurons

- dec function of VOR

- BPPV incidence inc with age

VOR affects what?

image stability with head movements

- dec in VOR = blurry = dizzy

inc in BPPV incidence

1 yr prevalence >60 years old

- estimated to be 7x higher

clinical implications of vestibular changes

- impacts activities with head movements

- more dependent on somatosensory inputs for balance (dec reliance on inner ears)

- postural response patterns are dec

- inc risk for vestibular disorders

- **FALL RISK

components of balance

inner ear, somatosensory, vision

- all can be affected by aging

age related somatosensory changes

- dec touch (LE>UE)

- inc cutaneous pain threshold (UE>LE)

- dec proprioception (LE>UE)

dec proprioception

- loss of joint receptor sensitivity

- beginning around age 50

pathological conditions

- stroke

- MS

- neuropathy

- parkinson's

- vestibular hypofunction

- cancer

- normal pressure hydrocephalus (NPH)

normal pressure hydrocephalus (NPH)

- urinary incontinence (wet)

- change in gait with feet on ground (wobbly)

- confused (wacky)

what is cognition?

mental action of the process of acquiring knowledge and understanding through thoughts, experiences, and the senses

what is "normal" cognition?

the ability of memory, language, perception, reasoning, perceptual speed, spatial manipulation, and executive skills

6 domains of cognitive function via the DSM-5

- learning and memory

- executive function

- language

- perceptual motor

- complex attention

- social cognition

learning and memory

- free recall

- cued recall

- recognition memory

- semantic and autobiographical

- long-term memory

- implicit learning

executive function

- planning

- decision making

- working memory

- responding to feedback

- inhibition

- flexibility

language

- object naming

- word finding

- fluency

- grammar and syntax

- receptive language

perceptual motor function

- visual perception

- visuoconstructional

- reasoning

- perceptual motor

- coordination

complex attention

- sustained attention

- divided attention

- selective attention

- processing speed

social cognition

- recognition of emotions

- theory of mind

- insight

changes in the brain affecting cognition

- inc amyloid plaques and neurofibrillary tangles

- dec gray and white matter and volume in the brain

- changes in neurotransmitter

dec gray and white matter and volume in the brain

in the frontal lobe

- important with executive functioning

changes in neurotransmitters

especially in dopamine

- changes in cognition

age related cognitive decline

no uniform decline in intellect throughout adulthood

- 60s = changes begin (not noticeable)

- 80s = changes may start to impact everyday life

- most significant decline = years preceding death

types of intelligence - crystalized intelligence

accumulation of knowledge and skills over time

- maintains or improves with age

types of intelligence - fluid intelligence

speed, ability to reason and problem solve

- declines with age

most common cognitive deficits

- attention

- speed

- memory

- reasoning

types of memory - sensory

- iconic (visual)

- echoic (auditory)

- haptic (touch)

sensory memory with aging

stays the same except in presence of physical sensory impairments

- sensory deficits = NOT normal aspect of aging

short-term memory

part of every cognitive test

- stays the same but may need more effort as someone ages

- does NOT stay the same with a pathologic condition such as alzheimers or dementia

long-term memory - implicit

subconscious influence of previously encountered info

- automatic with no conscious effort needed

- remains stable until late stage cognitive deficits

- reason for giving simple commands

long-term memory - semantic

facts, meanings, concepts

- with aging = gradual/linear decline of recalling facts

long-term memory - episodic

memory of events and emotions

- gradual decline as we age

changes that are deemed pathologic

- deficits in short-term memory

- deficits in implicit memory

- abrupt change in cognition

- deficits in language

functional impairments cognitive changes could have on older adults

- driving safely

- turning head R and L

- attention speed/problem solving

- IADLs

- medication compliance

- quick processing speed

- inc in fall risk

- deficits executive functioning

what do cognitive deficits mean for PTs?

- sensory cues (visual, touch, sound)

- eliminate distractions

- inc repetition (helps implicit learning)

- inc processing time

- let pts experience failures/errors safely

- incorporate cognitive tasks in treatment sessions

- encourage successful cognitive aging

activities associated with high cognitive function

- puzzles, discussion groups, reading, using the computer, playing bridge, board games, musical instruments

- complex careers

- high educational attainment

- exercise

- gardening, dancing, social engagement

- travel

continuum of cognitive changes - preclinical

no symptoms but brain changes have begun

continuum of cognitive changes - mild cognitive impairment

- memory or other cognitive complaints

- abnormal when formally tested

- impairment is not bad enough to get in the way of daily functioning

continuum of cognitive changes - dementia

- memory and other cognitive difficulties bad enough to impact daily life

pathological cognitive conditions

- mild cognitive impairment (MCI)

- dementia

- delirium