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Long Range Mount Installation
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2005-2010 SR Research Ltd.
Figure 7-10: Screen Mount used in conjunction with the
Elekta Neuromag screen (left) and a custom-built wood-frame
screen (right)
7.9
MRI Installation
Before beginning installation in an MRI environment, please be sure to
familiarize yourself with the earlier portions of this chapter. This section is
essentially duplicating Section 7.7 but with specific mention of the MRI
environment and components.
Installation in MRI settings will vary as different sites often have unique solutions for
presenting visual stimuli. Placement of the screen, the head coil type and other site-specific
factors must be considered in positioning of the eye tracker. The Fiber Optic Camera and Long
Range Illuminator are designed to operate at the opening of the bore or even in the bore where
appropriate mounts exist. Typically, it is desirable to position the Mounting Bar with the
Camera Head and Illuminator directly below the visual display. This will use some potential
space at the bottom of the visible display area, but both Camera Head and Illuminator need to
be visible to the participant. Infrared reflecting first-surface mirrors on the head coil optimize
the eye-tracking signal, with mirrors for several models of head coil available from SR
Research.
A list of tested configurations appears in Table 3 and Table 4, along with comments about
positioning the mount. Binocular recording is noted as ‘possible’ because it relies on the ability
to view both eyes simultaneously in the angled camera view, which may be contingent on the
stimulus display, the lens required and other site-specific physical factors that may vary
between installations.
