Place Thumbs Under The Net's Perimeter Band - Geodesic Sensor Net Technical Manual

6: Applying the GSN
Let the Net hang only from your thumbs and visually check the structure for
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any tangling.
Hook your little fingers into the lowest band at the back of the Net, which is the
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perimeter band. (If your hands are small, hook your little fingers into the
perimeter band of the Net as far back as you can reach.)
Stretch the Net by using your thumbs and little fingers that are hooked into the
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perimeter band and open the perimeter so that it forms a circle. (For support,
you can straighten your other fingers inside the Net, lightly touching the
structure with only the fingertips.) Adjust your hands, as needed.
Gently flip the Net upright so that you are ready to apply it to the subject's
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head.
Initial Application
In general, a good application results from standing directly in front of the subject,
stretching the perimeter band to the proper size, and applying the Net by pulling
straight downward over the subject's head.
The HCGSN features a tighter web structure than the GSN 200, which can make it
challenging to achieve an evenly spaced application. As mentioned at the beginning
of this chapter, we recommend that you practice applying a "dry" Net (one without
electrolyte) on a colleague. Evenly spaced electrodes are important for data analysis
such as grand averaging.
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Figure 6-8. Place thumbs under the Net's perimeter band
Geodesic Sensor Net Technical Manual
S-MAN-200-GSNR-001 • January 31, 2007