Chapter 9 Flashcards
What is the sensory weighting hypothesis?
When one sensory system is less reliable, the input to the CNS from that system is weighted less heavily, and inputs from other systems will be weighted more heavily
What occurs when a patient has a dome on their head?
Vision becomes inaccurate
What occurs when a patient has a blindfold on?
Vision is not used
What occurs when a patient stands on a foam pad?
Somatosensory becomes inaccurate
What occurs in healthy young adults as the go through the six sensory conditions?
The sway index gradually increases
What are the six sensory conditions?
1 = nothing 2 = blindfold 3 = dome 4 = foam 5 = foam + blindfold 6 = foam + dome
What does the CTSIB do?
Helps to determine which sensory system an individual relies on to maintain balance. Examines standing balance under various conditions
What are the 2 major factors that contribute to aging?
1) Primary/Genetic Factors
2) Secondary/Experiential Factors
What are primary factors of aging?
Factors that contribute to the loss of neuronal function within a system over which we have little control
What are secondary factors of aging?
Factors such as environment, nutrition and lifestyle, effects on our nervous system function over which we have more control
What is the lifestyle like of an older adult with a disability?
Dependent in all BADLs
What is the lifestyle like of a physically dependent older adult?
Cannot pass some of all BADLs (walking, bathing, dressing, eating, transfers)
Needs home or institutional care
What is the lifestyle like of a physically frail older adult?
Light housekeeping, food prep, grocery shopping, can pass some IADLs, all BADLs, may be homebound
What is the lifestyle like of a physically independent older adult?
Very light physical work, hobbies (walking, gardening), low physical demand activities (golf, dance, crafts, travel, driving), can pass all IADLs
What is the lifestyle like of a physically fit older adult?
Moderate physical work, all endurance sports and games, most hobbies
What is the lifestyle like of a physically elite older adult?
Sports competitions, senior olympics, high risk and power sports (hang-gliding, weight lifting)
In those 65 and older, how many fall each year?
1 in 3
Falls make up ____ of unintentional injuries, which are the ___ leading cause of death in the elderly.
2/3, 5th
____ of deaths from falls occur in those 65 or older.
3/4
How much have falls cost the US?
$30 billion in 2010
What are the intrinsic risk factors for falls in community dwelling older adults?
- age and gender
- physiological and psychosocial factors (mm weakness, visual/gait/balance deficits, history/fear of falls, social isolation, anxiety, depression)
- cognitive impairments
- impaired ADLs
What are the extrinsic risk factors for falls in community dwelling older adults?
Environmental factors (rugs, stairs, slippery surfaces, poor lighting)
Fall are a result of _____.
The interaction of the individual, the task and the environment
What changes occur in the musculoskeletal system?
Reduced ROM
Diminished spinal flexibility
Altered posture
Decreased muscle strength
What postural changes occur?
Forward head
Increased kyphosis
Increased lordosis lumbar spine
Increased hip, knee flexion
What changes occur in muscles due to aging?
# of motor units decline Loss of some type II fibers
How do older adults respond to a moving platform that causes postural sway?
Slow response onset in key muscles (increased latency)
Increased co-activation to stiffen the joint
What occurs in stable older adults when perturbation and velocity increase?
Increased amplitude of response compared to young adults
What occurs in unstable older adults when perturbation and velocity increase?
Exhibit much more increased amplitude of response
What are some of the different mechanisms that are strongly correlated with balance?
- Sensory/Motor system function
- Muscle weakness
- Impaired synergy of muscle coordination and response to instability
- Limitation to adapt movement in reaction to changing tasks
What are some compensatory mechanisms used in aging?
Stepping reaction
Reaching reaction
What type of falls can arise from a forward stepping reaction? + a lateral step?
Forward = AP fall Lateral = ML fall
What type of fall can arise from a sidestepping pattern?
Not likely, much better than crossover step
What type of fall can arise from a lateral stepping reaction?
AP fall
What age related changes occur in the somatosensory system?
Vibratory sensation threshold increases
Tactile sensitivity decreases (increased threshold to touch stimuli)
What age related changes occur in the visual system?
Visual threshold increases
Visual acuity decreases
What age related changes occur in the vestibular system?
Reduction in vestibular function, loss of 40% of vestibular hair by age 70
What occurs in older adults when one sense is reduced?
They do not sway significantly larger than young adults
What occurs in older adults when 2 senses are reduced?
Significant effect on steadiness
Why might older adults (70 - 80) begin to have difficulty maneuvering around?
Reduced ability to integrate balance adjustments into ongoing voluntary movements
What problems do older adults have with anticipatory postural abilities?
Problems making adjustments quickly and efficiently
What problems can occur due to older adults impairments with anticipatory postural ability?
Falls, postural control is often used proactively to stabilize the body before making voluntary movements
Older adults show ____ reaction time of pressing a button when hearing a sound under dual-task conditions.
increased
What is an example of a dual-task that can be used in a clinic?
10 meter walk while subtracting by 3’s
What are the recommendations from the Geriatric Society to prevent falls?
- Fall in the past 12 months?
- If yes, frequency and circumstance of fall
- Difficulties walking or with balance?
- Those with fall(s) should be evaluated for gait, balance, etc
Aging is characterized by ____.
heterogeneity
