Projects
Specifying linguistic constraints on Visual processing
Many common real-world tasks require an interaction between Visual and linguistic processing, such as driving a car while getting
directions from a passenger. Given that these different processes have different temporal dynamics, it is reasonable to ask how one
process might impose constraints on the other during a task requiring interaction. With Gregory Murphy, a short-term memory
paradigm was developed to isolate such a linguistic constraint on Visual processing. Specifically, observers looked longer at objects
having names with more syllables, a finding that we replicated with faces assigned either 1- or 3-syllable surnames (Zelinsky &
Murphy, 2000). This finding blurs the distinction between separate Visual and linguistic processes underlying a working memory task,
suggesting instead that both types of process may be continuously interacting to determine behavior in the real-world.
Research Philosophy
Each time we engage in a moderately complex task, we likely enlist the help of an untold number of simpler
visuo-motor operations that exist largely outside of our conscious awareness. Consider for instance the steps
involved in preparing a cup of coffee. For the sake of simplicity, assume that the coffee has already been
brewed and is waiting in the pot, and that all of the essential accessories, an empty cup, a spoon, a carton of
cream, and a tin of sugar, are sitting on a countertop in front of you. What is your first step toward accomplishing this goal? The very
first thing that you might do is to move your eyes to the handle of the coffee pot, followed shortly thereafter by the much slower
movement of your preferred hand to the same target. Because the coffee pot is hot and the handle is relatively small, this change in
fixation is needed to guide your hand to a safe and useful place in which to grasp the object. After lifting the pot, your eye may then
dart over to the cup. This action is needed, not only to again guide the pot to a very specific point in space directly over the cup, but
also to provide feedback to the pouring operation so as to avoid a spill. After sitting the pot back on the counter (an act that may or
may not require another eye movement), your gaze will likely shift to the spoon. Lagging shortly behind this behavior may be
simultaneous movements of your hands, with your dominant hand moving toward the sugar tin and your non-preferred hand moving to
the spoon. The spoon is a relatively small and slender object that again requires assistance from foveal vision for grasping; the tin is a
rather bulky and indelicate object that does not require precise Visual information to inform the grasping operation. Once the spoon is
in hand and the lid to the tin is lifted, gaze can then be directed to the tin in order to help scoop out the correct measure of sugar. To
ensure that the spoon is kept level, a tracking operation may be used to keep your gaze on the loaded spoon as it moves slowly to the
cup. After receiving the sugar, and following a few quick turns of the spoon, your coffee would finally be ready to drink (see Land et
al., 1998, for a similarly framed example).
eye movements and visual cognition
