During this Tech Cast, Chris Rand discusses our mechanical stimulator, the 300C-I: Dual-Mode Indenter, an automated electronic von Frey device with the added capability to measure and control both force and length at a single point.  He highlights the specific hardware, how it works and the applications for each setting. He also covers the different tube extensions and tips that can be used to provide different areas of stimulation. For more, please visit: https://aurorascientific.com/what-hurts-the-most-mechanical-stimulation-made-easy-with-the-300c-i

1. What Hurts the Most?
Mechanical Stimulation Made
the 300C-I
www.aurorascientific.com
Chris Rand, MSc
Product Consultant
Aurora Scientific

2. 300C-I Dual-Mode Indenter
How does it work?
 Hardware
What can I measure?
 Common Experiments
How is it done?
 Experimental Setup and
Execution
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3. Hardware: Dual-Mode Lever System
Length Control
 Precise movement of motor
position (unitized or reference)
Force Control
 Precise application of force or
load (unitized or reference)
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 Fast step response (<2ms)
 Superior resolution (0.3mN)
 Operates in any spatial
orientation
 Application area remains
constant
 Mountable, minimizes off-axis
force application
Hardware: Servomotor

5. Extension tube
 Extends application area away from motor case
 Easy coupling to indenter tips
Indenter Tips
 3D printed
 Set of 7 (0.3mm – 3.0mm)
 Vary application area
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Hardware: Indenter Extension Tube
and Tips

6. Allodynia
 Pain response to non-painful stimuli
Hyperalgesia
 Increased response to normal pain
threshold
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Common Experiments:
Mechanosensitivity
Felix Viana (2018);Adapted
from Cervero F, Laird JM (1996)

7.  Elicit sinusoidal tactile stimulation of foot, hand,
tissue, etc.
 Measure subject sensitivity or reflex response to
varying frequency of stimulation
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McKeown et al. 2016
Common Experiments:
Vibrotractile Sensation

8. Common Experiments:
Receptive Field
 An area innervated by free nerve endings of
a single nociceptor that respond to
mechanical stimuli;
smaller = greater location acuity
 Can be mapped out by varying location of
noxious stimulus and recording nociceptor
activity in response
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work by Cenveo

9. Indentation Distance
 Control depth of mechanical stimulation
 Indent, hold for defined time and release
 Vary depth of stimulation to elucidate
information about tissue or material stiffness
or deformation properties
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Experimental Setup

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Execution

11. Vibrotractile
 Apply sinusoidal stimuli to hand,
foot or other tissue
 Vary frequency and amplitude of
stimulation (i.e. 25Hz to 250Hz)
 Measure response from subject,
tissue or nociceptors
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Experimental Setup

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Execution

13. Constant Load
 Mechanically stimulate receptive field of
nociceptor(s) with constant force (mN) or
pressure (kPa; mN/mm2)
 Vary load (i.e. 250mN to 400mN), application
area (i.e. 0.3mm to 3.0mm) and velocity of
stimulation
 Measure firing rate of nociceptors
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Experimental Setup

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Execution

15. Summary:
A Mechanical Stimulator That…
 Produces precise, repeatable mechanical stimulation for nociception and/or
somatosensation experiments
 Eliminates user induced variability and need for multiple threshold tests
 Minimizes off-axis forces
 Delivers continuous application area over full force range
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