Lesson 6 - Sensory Physiology Flashcards
Who was the first scientist to classify the five senses: sight, hearing, taste, smell, and touch?
Aristotle
This is a branch of biology that studies the functions of sensory organs and their ability to process stimuli from the external environment.
Sensory physiology
Fill in the Blanks:
One’s sense is a system that consists of a __________ that respond to a specific kind of __________, and that correspond to a defined region within the brain where the signals are received and interpreted.
Sensory cell type; Physical energy
What are the 10 senses?
- Sight
- Hearing
- Taste
- Smell
- Touch
- Joint Position
- Vibration
- Temperature
- Pain
- Proprioception
At the cellular level, mechanoreceptors are activated by __________
Changes in pressure
At the cellular level, photoreceptors are activated by __________
Light
At the cellular level, chemoreceptors are activated by __________
Chemicals
At the cellular level, thermoreceptors are activated by __________
Changes in temperature
At the cellular level, nociceptors are activated by __________
Pain caused by extremes of the other senses
This is a process by which a sensory system becomes insensitive to continuous stimulation
Adaptation
In adaptation, __________ is the only sense that does not adapt.
Nociceptors, because it is essential for survival.
This responds to varying intensities and frequencies of pressure.
Tactition (Touch)
Where are tactile receptors for touch found?
Skin, muscles, and viscera
This is found in hairy and glabrous skin on the fingertips. It is able to detect corners, edges, and curves.
Merkel’s disc
This is found in hairy skin for stretching.
Ruffini nerve endings
This is found in glabrous skin (palm and finger). It is the most sensitive.
Pacinian corpuscles
This is found in glabrous skin and is sensitive to dynamic changes in the skin.
Meissner Corpuscle
This is a perceived sensation in response to stimuli that cause tissue damage.
Nociception (Pain)
Where are nociceptors found?
Skin, muscles, joints, and viscera
What are the two types of pain?
- Fast Pain
- Slow Pain
This pain is carried by myelinated Type A-delta fibers.
Fast pain
This pain is carried to unmyelinated Type C fibers.
Slow pain
Where are temperature receptors found?
In the subcutaneous layer of the skin
Cold receptors are sensitive to temperatures __________.
Below 37ºC
Warm receptors are sensitive to temperatures ____________.
Between 35ºC to 45ºC
This is referred to as the body’s internal thermostat.
Hypothalamus
Gustation has at least four types of taste bud receptors. What are they?
- Sweet
- Salt
- Sour
- Bitter
The ‘umami’ receptor detects the amino acid, __________.
Glutamate (Glu)
Taste is a combination of what senses?
- Taste receptors
- Olfactory receptors
- Touch (mouth feel)
- Temperature
- Sight
Where are olfactory receptors located?
In the roof of the nasal cavity
What is the process of olfaction?
- Odor molecule binds to olfactory receptor
- Action potential is triggered
- AP is carried to the brain
Hearing is also known as ___________.
Audition
It is the sense of sound perception.
Hearing
What is the normal range of hearing?
20 to 20,000 Hz
This is the detection of sound waves as vibrations by the body.
Tactition
What are the steps of hearing?
- Stimulus
- Vibration of tympanic membrane
- Detection of vibration by hair cells in the inner ear
What are the two tests for hearing?
- Weber’s test
- Rinne’s test
In the Rinne’s test, this is performed by pressing the base of the tuning fork against the MASTOID PORTION and noting the duration that the sound can be perceived by the subject.
Bone conduction
In __________, immediately place the prongs of the
fork 2 cm away from the EXTERNAL AUDITORY MEATUS the ear once no sound is perceived in bone conduction
Air conduction
What is considered a normal result in the Rinne’s Test?
AC > BC in both ears
What is considered a normal result in the Weber’s test?
Midline
This is referred to as the perception of balance.
Equilibrioception
Equilibrioception is controlled by?
- Vestibular system in the inner ear
- Cerebellum
What are the two components of the vestibular system?
- Semicircular canals
- Utricle and saccule
Semicircular canals contain fluid known as __________ that detects rotatory movements of the head.
Endolymph
The utricle and saccule are __________ that detect linear acceleration and the effects of gravity.
Otolith organs
This aids in the detection of gravity.
Calcium carbonate crystals
This is the perception of body position
Proprioception
This is the ability to detect electromagnetic energy.
Vision
What is the visible spectrum?
380 nm to 750 nm
The brain interprets the image collected by the __________ in the eye as ‘sight’
Photoreceptor cells
This is responsible for color differentiation and found in the Fovea of the eye.
Cones
This is responsible for light and dark contrast.
Rods
This is the region with highest visual acuity, in which cones are predominantly found.
Fovea
This is known as the blind spot due to the lack of receptors. It is also where the nerves and retinal blood vessels enter and exit.
Optic disc
This is referred to as extremely rapid eye movement
Saccadic masking
Remember from PHYSIOL: fast movements = saccades
TRUE OR FALSE: During the rapid movement, the optic nerve ceases to transmit visual information
TRUE
What are the corresponding peak sensitivities of each cone?
Red -
Green -
Blue -
Red - 564 nm
Green - 534 nm
Blue - 420 nm
This occurs when people lack one or more sets of cones OR have cones that respond to different peak frequencies
Color blindness
What are the four types of color blindness?
- Red-green color blindness
- Yellow-blue color blindness
- Full color blindness
- Blue color blindness
This type of color blindness is the most common congenital color blindness.
Red-green color blindness
These two types of color blindness are rare.
Full color blindness and blue color blindness
What is the altered sensitivity and complete deficiency in red cones?
Protanomaly and protanopia, respectively
What is the altered sensitivity and complete deficiency in green cones?
Deutanomaly and deutanopia, respectively
What is the altered sensitivity and complete deficiency in blue cones?
Not seen and tritanopia, respectively
