special senses Flashcards
Describe three anatomically different types of sensory receptors
Interoreceptors
exteroreceptors
proprioceptors
Interoreceptors
Monitor internal systems such as digestive and repiratory; are responsible for stretch, deep pressure, and pain in viscera
Exteroreceptors
External senses such as touch, temperature, and pressure and distance/special senses
Proprioceptors
Monitor position and movements
Explain the difference between a general sense and a special sense
General senses have receptors distributed widely throughout the body while special senses have receptors confined to head structures
Describe the process of transduction
translation of arriving stimulus into an action potential by sensory receptors
What senses does the frontal lobe control
taste and smell
What senses does the parietal lobe control
taste
What senses does the temporal lobe control
Hearing
difference between a sensation and a perception
A sensation is the sensory information arriving to the CNS while a perception is the conscious awareness of a sensation
Sensory adaptation
Ability to ignore unimportant stimuli
Peripheral adaptation
sensory receptors may stop sending AP even if stimulus is still present (room temperature)
Central adaptation
CNS ignoring an AP from a sensory receptor (house smell)
Example of sensory receptor responding to other stimuli
RUbbing your eyes and seeing flashes of light. the stimulus is mechanical and not visual but the receptors respond.
What is a labeled line?
A link between a peripheral sensory receptor and cortical neuron
What is modality?
What is perceived after a stimulus
Four classes of sensory receptors grouped based on their stimulus sensitivities?
Nociceptors
THermoreceptors
Mechanoreceptors
Chemoreceptors
Nociceptors
Pain receptors that respond to chemicals released during tissue damage, extreme temperatures, and mechanical damage. Adapts very little
Thermoreceptors
Respond to changes in temperature
Mechanoreceptors
Respond to mechanical forces and sense changes that deform the receptor (touch, stretch, and pressure)
chemoreceptors
Respond to changes in chemical concentrations
What function does pain serve?
Allows perception of damage to tissues and motivates the individual to withdraw from damaging situations
Fast pain
-Acute pain
- Well localized and conducts impulses rapidly
-Myelinated
Slow pain
- Thin unmyelinated
-Conducts impulses more slowly
-Chronic pain
What parts of the brain regulate pain impulses
Thalamus allows awareness, Cerebral cortex judges intensity and location
Referred pain and example
Pain sensations originating in visceral organs are perceived as involving specific regions of the body surface innervated by the same spinal nerves
theory of referred pain
nociceptors from several locations converge on a single ascending tract in the spinal cord
Two classes of thermoreceptors
Warm receptors, cold receptors
Three classes of mechanoreceptors
Tactile
Baroreceptors
Proprioceptors
Tactile receptors
Provide the sensation of touch, pressure, and vibration
Baroreceptors
Detect pressure changes in the walls of blood vessels and in portions of digestive and respiratory tracts
Proprioceptors
Monitor positions of joints and muscles, the most structurally and functionally complex of general sensory receptors
Free nerve endings
Sense itching, pain, temperature, and pressure
Root hair plexus
Monitor distortions and movements across the body surface wherever hairs are located
Tactile discs
Also called merkel discs
Fine touch and pressure receptors
extremely sensitive tonic receptors
Lamellated corpuscles
Detect heavy pressure and vibrations
Ruffini corpuscles
Sensitive to pressure and distortion of the skin
Tactile corpuscles
IN hairless portions of skin and lips, detect touch and distinguish between two points on the skin
how are Sensory and motor tracts of the spinal cord named
Name indicates position and direction of signal
