This experiment seeks to examine the role of planning or "look ahead"
fixations in natural tasks and how the scene information transferred
across saccades may influence eye, hand, and head coordination.
Neil Mennie (Principal Investigator)
Mary Hayhoe (Co-Principal Investigator)
Brian Sullivan (Research Assistant)
Carol Walthew (Data Analysis)
Neil Mennie
Example of the experimental setup the subject's eye movements are tracked
via a head mounted eye tracker. Hand movements are tracked via electro-
magnetic sensors attached to the back of the hands. A similar sensor
also tracks head motion. Subjects assemble sequences of wooden peices
into models several times during an experimental trial. With the data
collected subjects eye fixations and body movements can be segmented and
analyzed for the temporal associations related between actions.
The larger problem is to investigate certain aspects of human visual
perception. Through investigating the eye movements that humans deploy in
the course of a natural task, this project seeks to shed some light on the
role of certain fixations that fall upon task specific objects prior to
their use. These fixations may be indicative of planning a motor action,
and if evidence to support this hypothesis is found then it suggests
that information necessary for action can be transferred across
intervening fixations. Provisional results show that by manipulating the
goals of a natural task - building a wooden model, the number of these
"look-ahead fixations" can be manipulated. This has huge implications for
research into the role of memory in tasks that involve everyday action.
This is important for several reasons. Firstly, it suggests that
information necessary for a reach can be acquired several seconds ahead of
the current task, and that it is not in eye centered co-ordinates. This
conflicts with much of the published data. Secondly, it suggests a much
greater role for planning in active tasks than was previously thought, and
it also shows that information specific for successful action can be
transferred across saccades. It is too early to give any examples of
direct results, and data analysis is currently continuing.
eye hand coordination, eye movements, eye movements in natural tasks,
eye tracking, hand movements, head movements, look ahead fixations,
visual scene memory, saccadic transfer