{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

16 Somatosensory Receptors

Receptor 34c cold receptor 27c 21c warm cold dynamic

Info icon This 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: or 34C cold receptor 27C 21C warm cold dynamic response static response 27C 21C dynamic response static response Static Response (im mp/s) warm thermoreceptors cool thermoreceptors cold cold polymodal nociceptors nociceptors Static Response (im mp/s) nociceptor hot "paradoxical" nociceptors response hot Somatosensory Receptors Sustained response for static receptors: -Sharp cutoff for warm receptors at 45C -Dynamic response for receptors is wider cool -For extreme ranges: PAIN! thermoreceptors cold cold -Response by nociceptors polymodal October 20, 2010 warm thermoreceptors 10 20 30 40 Skin Temperature (C) 50 60 nociceptors nociceptors hot nociceptor hot "paradoxical" nociceptors response Type 3: Nociceptors - Free nerve endings in skin or muscle, etc. = look the same10 thermoreceptors as 20 Nociceptors 11 30 40 Skin Temperature (C) 50 60 Free nerve endings in skin or muscle, etc.; look the same as Group A:# High-threshold mechanoreceptors = `prickling' pain (not excruciating) thermoreceptors. # # - Myelinated, large diameter Group A High-threshold Group: C:$ sensation mechanoreceptors; conveys `prickling'diameter - Unmyelinated, small pain 1) 1) polymodal nociceptors: respond to tissue injury (i.e. Polymodal nociceptors: respond to tissue injury = `burning' pain (excruciating) Group C: 2) acidity in many cases); `burning' pain have TRPV1 channels Heat pain afferents: 2) heat pain afferents; have TRPV1 channels 3) 3) freezing pain afferents afferents Freezing pain 4) 4) mechanical pain afferents afferents Mechanical mechano-insensitive; some 5) `sleeping' nociceptors;pain respond to histamine, mediate itch 5) `Sleeping' nociceptors: usually not active; mechano-INsensitive # # # # # some respond to histamine -> mediate itch (allergies) Separate populations of group C afferents conveying heat pain and mechanical pain. Hot -There are specialized nociceptors in group C -Sensory axons will terminate at diff layers in spinal cord (dorsal horn) -Heat nociceptors: start responding around 45C (weak initial response at ON line) -At 50C: stronger response (faster, more sustained firing rate) Heat Nociceptor Warm 5 of 5 12...
View Full Document

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern