Following initial characterization of their visual field loss, the participant's
performance in reading tasks will be measured with and without remapping. Tasks will
include reading groups of random letters, words, simple sentences, and "natural" text
from the environment (taken from phone apps, signage, etc). Different kinds of remappings
will be used by participants, including traditional and personalized remapping. For
control observers, differently shaped artificial scotomas will be used.
Participants interested in the study will be brought in for an initial visit. All
participants will be administered the MMSE. Observers who pass the criteria for the study
will then have the remainder of the procedures described to them verbally prior to
undergoing the remainder of the consent process (see below). Participants will then
undergo a standard exam at the UMN eye clinic, if they have not had one within the last
month.
Participants will then have their scotomas mapped using a microperimeter housed in the
psychology department to give size and shape information. Additional perimetry may also
be conducted using either of the two displays (either HMD or desk mounted computer
monitor) we have developed. Here, patients will be asked to fixate at a spot on screen
and identify visual stimuli presented at different regions of the screen. The size and
locations of visual stimuli patients were unable to identify will provide the size and
location of the scotoma. Another additional manual perimetry protocol may be conducted as
well. This would involve asking subjects to fixate at the center of a tangent screen, and
asking them to identify dots temporarily presented on the screen by the researcher using
a laser pointer. The locations of dots that patients are unable to identify will provide
the size and location of the scotoma. The location and extent of each eye's scotoma and
PRL will be used as software inputs on either device. Perimetry using one or all of the
methods above will be performed until acceptable information about the scotoma extent and
location is obtained.
In a second visit, participants will perform the visual tasks that are used as the basis
of their personalized remapping, letter perimetry. Participants will first view and
report three randomly selected horizontally arranged letters placed at different
locations in the visual field. This letter perimetry task will take about 40 min and will
cover a large part of the visual field.
Participants will then read single words whose letters have been displaced from
horizontal in various ways that comprise candidate remappings generated on the basis of
the letter perimetry results. This personalization test will take about 40 minutes, and
will find a good remapping strategy for the individual. Subjects will then be introduced
to the reading tasks that comprise the remainder of the study
In 6 additional sessions, participants will perform various reading tasks using different
remappings. In all of these, text will be displayed on the screen, and the task is simply
to read aloud what was presented. Two sessions will involve reading single words, one
session will involve reading strings of 3 letters that are not arranged horizontally, two
sessions will involve reading short sentences, and one session will involve reading
naturalistic text (from phone apps, signage, menus, etc). In all sessions, some reading
will be with remapping, some will be without. Both traditional and personalized remapping
will be used.
In all these sessions, the eye tracker will be calibrated to participants' individual
head and eye position. This will involve fixating at different points on the device
screen (HMD or desk-mounted) as the eye is imaged by the eye trackers. This may take up
to 45 minutes in the initial session, if various combinations of head and eye positions
are required for the eye trackers to work well. But once completed, calibration is much
faster in subsequent sessions. Quick perimetry validation may also be conducted in each
session.
Throughout all testing, patients will be asked if they feel any discomfort, and will be
able to take a break or quit testing at any point.
Including the initial visit, testing for any given patient is anticipated to last no more
than eight sessions over eight weeks. Enrolling participants, testing, and data analysis
for all participants is anticipated to take five years from the date of enrollment of the
first participant.