chapter 15 review Flashcards
What are the main events that occur along the sensory and motor pathways?
- depolarization of sensory receptor (stimulus)
- action potential generation
- propagation (sensory info distributed)
- cns processing- then leads to an involuntary or voluntary motor response
What is the difference between the afferent and efferent divisions of the nervous system
Afferent- somatic and visceral sensory pathways to brain
Efferent- motor pathways towards effectors
What is the difference between general and special senses
Special senses use bipolar neurons and use specific special organs that only response to one sense
ex: smell, taste, vision, equilibrium, hearing
general: touch, vibration, pain, temperature, proprioception
What are receptive fields?
areas monitored by a receptive cell that receives sensory stimulus info
Define adaption
a reduction of receptor sensitivity in the presence of constant stimulus
What is the difference between fast and slowing acting receptors
fast acting respond to stimulus rapidly, then gradually decrease
slow acting are always functioning in the background
What is the difference between tonic and phasic receptors
tonic are always on (like pain) and are slow adapting
phasic waits for a stimuli to “turn on” and are fast acting (temperature)
what are 4 types of general receptors and their functions
nociceptors- pain
thermoceptors- temperature
mechanoceptors- physical distortion like touch
chemoceptors- monitor chemical concentrations
What are the mechanoreceptor classes
tactile receptors: touch, pressure, vibration ex: free nerve ending, merkel discs, meissners, pacinian
baroceptors: monitor visceral pressure changes like blood vessels
proprioceptors: monitor position of skeletal muscle and joints
What is the difference between 1st, 2nd, and 3rd order neurons?
1st: sensory neurons that delivers sensations directly to CNS
2nd: interneuron (in spinal cord or brain stem)
3rd: awareness of sensation, synapses in thalamus
What is phantom limb pain?
pain and other sensations felt by amputated part of body
What is referred pain?
pain that is felt by a different part of the body than the one that is actually causing the pain
ex: heart attacks in men are normally felt as arm pain
What is the sensory homunculus?
a map of distorted body feature that show where the most sensory neurons are
What type of info is carried by visceral sensory pathways?
interceptors detect sensory info in visceral cavities
What is the difference between upper and lower motor neurons and their location
upper: CNS processing center in the primary motor cortex
lower: brain stem or anterior gray horn of spinal cord, together they innervate skeletal muscle
