Term
Sensory System
Receptor potential |
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Definition
-convert stimulus into change in membrane potential
:depart from resting potential
-graded stimulus: min stimulus reqd to activate receptor from "baseline"
can cause threshold |
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Term
Sensory
primary receptive field |
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Definition
-physical area where receptor responds
-PRF overlap. convergence occurs (receptor info is condensed) decreases sensitivity
-all is integrated in the CNS |
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Term
Sensory
Distinguishing Stimuli |
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Definition
1. Modality-Type of stimuli
1.a.Quality-what subtype->i.e.color
2. location-sensory regions highly organized
3. intensity- strength of stimulus (more AP/time)
4. Duration: sustained AP firing
-receptors adapt in presence of continuing stimulus. |
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Term
Sensory
Somatic senses and pathways |
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Definition
-touch, temp, orientation, pain, internal conditions
-prim. neuron (sensor/receptor)->spinal cord->thalamus->higher brain (somato sensory cortex)
-primary->secondary->tertiary neuron |
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Term
Sensory
Somatic Sense Nociception |
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Definition
1.Nociceptors-free nerve-endings in the skin either physical or chemical
2.fast pain-sharp, localized and myelinated
3. slow pain-dull, diffuse; unmyelinated
-aware of pain by the thalamus, in somatosensory. |
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Term
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Definition
| (vision, taste, hearing, smell). By chemoreception (smell, taste) |
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Term
| Special Sense-smell (chemoreception) |
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Definition
-olfactory cells->true neurons (on top of nasal cavity
a. dendrites are called cilia (have membrane receptors->odorant receptors
b. unique receptor for each olfactory cell
c.each receptor binds odorants by similar structure (GPCR->cAMP open ion channels
d.placement of olfactory cell is interpreted by the brain
e. odorants can bind more than one receptor
f. convergence of sensory neuron in glomeruli; terminates in olfactory cortex |
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Term
| Special sense-taste (chemoreception) |
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Definition
Papillae->taste buds->taste cells (sensory cells that release nt onto neurons)-> AP to gustatory cortex
-Receptors can be GPCR or ion channels: Ca influx releases nt |
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Term
| Special Sense (mechanoreception) |
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Definition
-pressure (hearing)
1. ear participates in equilibrium and hearing
2. hearing is perception of pressure waves
-frequency (Hz-waves/sec) ->pitch
-amplitude as loudness
-tone quality:timbre- distinguishes different freq contained in same pitch (harmonics) |
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Term
| Mechanoreception with sound perception |
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Definition
| Pressure waves-> mechanical vibrations->-> ->fluid vibration->chemical signaling-> AP to auditory cortex |
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Term
| Mechanoreception in Cochlea's inner ear |
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Definition
Fluid waves via oval window move basilar and techtorial membranes
-cilia on hair cells move\
a. depolarize (cation channels (K)open open and CA channels-> nt release
b. hyperpolarize by other direction
-volley principle: "in sync" with pressure wave (loudness is # of AP/ unit time)
-Place principle: pressure wave temporal info translates into spatial coding -> place on cochlea
a. auditory cortex "topotonically mapped"-every place in bailar membrane represented in cortex |
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Definition
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