{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

16 Somatosensory Receptors

No work in long term but are slowly conducting but

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: ork in long-term but are slowly conducting BUT efferents are fast-conducting - Length restoration eventually comes after sustained contraction Somatosensory Receptors October 20, 2010 8 Group II & III Proprioceptors: Joint receptors - Attach to capsule enveloping joint - Golgi-Mazzoni corpuscles (paciniform) respond to orthogonal forces - Ruffini endings respond to capsule strain (tangential forces: extending joint) Type 2: Thermoreceptors - Location: free nerve endings in skin - Warm: group C; respond to skin temps from 25-45C (>45C: noxious!) - Cool: group A; respond to skin temps from 10-28C (<10C: afferents anesthetized) - Slowly adapting but strong phasic component - Like Ia muscle spindle: strong dynamic component - No specialized capsules around them: no assoc cells at terminals = free nerve endings - True also for nociceptors: histologically, they look the same! Or look for... - All have receptor proteins `TRP' (transient receptor potential) cation channels 9 4 of 5 Somatosensory Receptors October 20, 2 PSL302Y: Lecture 15, by Prof. MacKay# 40C 34C Wed., Oct.20, 2010 Thermoreceptors: response Skin Temperature - Warm receptors respond to skin T warm - Strong phasic component (respond to rate receptor of change) cold Somatosensory Receptors receptor - Also sustained asOctober 20, 2010 T maintained long as - Cold receptor silent - Warm receptors fall into group C b/c unmyelinated, S diam = slow conducting - Cool skin down: phasic burst in cool receptor warm - Cool receptors fall into group A b/c cold myelinated, S diam = quickly conducting - Must respond to cool stimuli more quickly b/c we're warm-blooded creatures - Dynamic range broader than static range of receptors 40C Skin Temperature warm recept...
View Full Document

{[ snackBarMessage ]}