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Models 16011 & 16012 User’s Manual
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DESCRIPTION:
The Model 16011 Aesthesiometer is a basic sensory device designed to measure a subject’s
perception of the cutaneous two-point threshold. The unit is designed with calibrated Vernier
construction for accurate measurements and strong brass tips insulated with a coating of vinyl to
minimize the influence of temperature on touch and/or pain thresholds. In addition, the Model
16012 incorporates a single third point adding to the flexibility of the unit since it is now possible to
alternate between single and double point stimulation without changing the vernier setting.
OPERATION:
1.
Blindfold the subject and set the two points of the Aesthesiometer close together.
2.
Both points are touched to the skin simultaneously and the subject is requested to report
whether he feels one or two points.
3.
The separation of the points should be gradually made larger until the subject reports two
points. (As a check, only one point should be touched on some trials either by separating the
Model 16011 points so that only one can be used or by using the convenient third point of the
Model 16012.)
4.
The distance separating the points can be read directly from the calibrated scale on the
Aesthesiometer, giving an accurate measure of the subject’s two point threshold based on his
reported sensations.
When different areas of the skin are tested in this manner, it will be found that the two point
thresholds differed markedly. For example, the threshold is very small on the tip of the
tongue and quite large on the upper arm and parts of the back.
If the procedure is repeated a number of times on the same subject using the same skin area, it
will be found that the distance separating the two points become smaller and smaller,
indicating an increase in sensitivity brought about by practice.
Transfer effects can be studied by giving the subject one or two trials on one arm to determine
the threshold there, then giving him a large number of trials on the corresponding area of the
other arm, and then again determining his threshold on the first arm. It will be found that
there is a large increase in sensitivity in the first arm, even though there was no practice there,
brought about by the transfer effect from the second arm.