Completion of a model in
the Join-All condition.
In the video, the crosshairs illustrate where a subject
fixates during a simple model-construction task. The task
was to join together 4 wooden components of a childrens
model in a predetermined seqence. In this example the
sequence is simply 1 - 4. The subject would start by
picking up piece 1& 2 and then join them together
using a wooden nut and bolt. They would then pick up
piece 3 and join that to the part assembled model, and
then repeat this for piece 4. We were interested in the
occasions when the subjects looked-ahead to the last two
pieces (3 & 4) situated on the far left and right of
the table. We measured head, hand and eye movements
during the task (which took about an hour in total) and
looked at the influence that look-aheads might have on
subsequent movements of gaze and reaching. The video
shows the completion of 1 model, and you can see examples
of look-ahead fixations on both pieces 3 & 4 here.
Note that these fixations do not occur as often as this
video might lead you to believe. We find them occuring on
somwhere around 15-20% of reaches.
As the video might have finished playing while you were
reading this (demonstrating just how specific gaze can
be), I suggest you watch it more than once. You may need
to install Quicktime to see it.