Long bones do not significantly shorten with age

- long bones do not significantly shorten with age, thinning disks and shortening
vertebrae reduce the length of the spinal column= a decrease in height
- Height may be further shortened because of varying degrees of kyphosis, a backward
tilting of the head, and some flexion at the hips and knees
- A deterioration of the cartilage surface of joints and the formation of points and spurs
may limit joint activity and motion.
Nervous System:
might be unnoticed because changes are often nonspecific and
slowly progressing.
- cardiovascular problems can reduce cerebral circulation and be responsible for
cerebral dysfunction.
- decline in brain weight and a reduction in blood flow to the brain; however, these
structural changes do not appear to affect thinking and behavior
- reduction in neurons, nerve fibers, cerebral blood flow, and metabolism is known
to occur.

- Reduced cerebral blood flow is accompanied by a reduction in glucose utilization
and metabolic rate of oxygen in the brain
- Electroencephalograms show a decrease in functional connections
- Although β-amyloid and
neurofibrillary tangles are associated
with Alzheimer’s disease, they can
be present in older adults with
normal cognitive function.
- The nerve conduction velocity is
lower= manifested by slower
reflexes and delayed response to
multiple stimuli.
- Kinesthetic sense lessens.
- slower response to changes in
balance, a factor contributing to falls.
- Slower recognition and response to
stimuli is associated with a decrease
in new axon growth and nerve
reinnervation of injured peripheral
nerves.
- hypothalamus regulates temperature less effectively.
- brain cells slowly decline over the years, the cerebral cortex undergoes some
loss of neurons, and there is some decrease in brain size and weight, particularly
after age 55 years.
- Sleep regulations are altered, changes in the sleep pattern occur, with stages III
and IV of sleep becoming less prominent
- Frequent awakening during sleep is not unusual, although only a minimal amount
of sleep is actually lost.
Sensory Organs:
five senses becomes less
efficient with advanced age,
interfering in varying degrees
with safety, normal activities
of daily living, and general
well-being
Vision:
- Presbyopia

- The stiffening of the muscle fibers of the lens that occurs with presbyopia decreases
the eye’s ability to change the shape of the lens to focus on near objects and decreases
the ability to adapt to light.
- visual field narrows, making peripheral vision more difficult.
- difficulty maintaining convergence and gazing upward.
- pupil is less responsive to light because the pupillary sphincter hardens, the pupil size
decreases, and rhodopsin content in the rods decreases
- the light perception threshold increases and vision in dim areas or at night is difficult
- Alterations in the blood supply of the retina and
retinal pigmented epithelium can cause macular
degeneration,
- Macular degeneration= condition in which there is a
loss in central vision
- Changes in the retina and retinal pathway interfere
with critical flicker fusion
- The density and size of the lens increase, causing
the lens to become stiffer and more opaque.