Nervous System, Vision, Hearing, & Motion Flashcards
What are the three main segments of the nervous system?
1) Central
2) Peripheral
3) Automatic Autonomous or Vegetative
Describe the central nervous system.
Consist of brain and spine. Central processing unit and memory. All sensory units are directed here.
Describe the peripheral nervous system.
Links spine to rest of body, 12 cranial nerves that connect to organs in head, 31 pairs of spinal nerves connect muscle groups/sensory organs of body
Describe the automatic nervous system.
Unconscious operations (breathing, heartbeat, etc.), sympathetic or parasympathetic
Describe how the nervous system works.
Electrochemical signals sent from sensory organs and are analyzed by the brain
Describe habitation and adaption.
Habitation- keep stimulating until noticeable
Adaption- long term exposure leads to changes
What is visual field?
The area that you have input from your eyes (includes peripheral) (normally about 135 degrees 60 up 75 down)
What causes the blind spot that everyone has?
The location of the optic nerve.
Most mid-air collisions occur in what conditions?
VFR
When flying, what is the easiest aircraft to see?
One flying across the visual field.
If an airplane is on the intercept course, it will have little to no movement, True or False?
True
Describe monocular cues for depth perception.
Size, motion parallax (near object appear to be moving), obstruction, texture, linear perspective, apparent foreshortening
Describe binocular cues for depth perception.
Convergence- amount eyes move together to focus
Stereopis- overlap between rental images
Accommodation- closer objects make pupil larger
How long does it take for adaptation of rods rather than cones (night)?
30-45 min.
Describe long sightedness (hypermetropia).
Eye is too short, which leads to things close being blurry. Corrected by convex lens.
Describe short sightedness (myopia).
Eye is too long. Opposite of long sightedness. Corrected by concave lens.
Describe presbyopia.
The ability for the lens to change to meet the needs of the eye. Lens adjust to see things close. Loss due to age.
What is an astigmatism?
When light refraction is unequal within the median (adds distortion to vision).
Name the parts of the outer ear.
Ear flap, Ear canal. Used to focus sound.
Name the parts of the middle ear.
Auricle, tympanic membrane (ear drum), ossicles (hammer anvil stirrup), eustachian tube
Name the parts of the inner ear.
Semi-circular canals, cochlea, auditory nerve
What causes conductive deafness?
Infection and trauma to middle and outer ear. Causes temporary hearing loss and has treatment options.
What causes sensori-neural deafness?
Long term exposure to noise. Damages auditory nerves, brain, cochlea, and is usually irreversible. NIHL Noise Induced Hearing Loss starts temporary and becomes permanent.
Describe what happens in the 120-140 dB range.
120- discomfort.
130- ear pain.
140- ear drum ruptures
Is it possible to get hearing loss from 90 dB range?
Yes- long term exposure
True or False: Semicircular canals have to do with hearing.
False
What are some effective treatments for airsickness?
Scan outside aircraft, fresh air on face, cool individual, recline seat in turbulence, land when practicable
