Vlada Aginsky
Department of Cognitive and Linguistic Science,
Brown University
will speak on
Navigating with and without Landmarks in Virtual Reality
Abstract:
Humans and animals are able to switch from one navigational strategy
to another, depending on what type of environmental information appears
most reliable in a given situation. For instance, hamsters will rely on
visual landmarks until the landmarks are displaced so far from their
original location that they offer exceedingly divergent information from
path integration. At that point they switch to the path integration
strategy, which entails using proprioceptive signals during locomotion to
continuously update the animal's position relative to some starting point.
In this study our aim was twofold. First of all we were interested in
whether or not people will use path integration when landmarks are
available but are known to be less reliable than internally-generated
signals. Secondly, if people do decide to rely on visual landmarks - will
they choose to focus on a particular type of landmark, local or global?
Using a virtual reality environment, subjects moved through a tunnel
containing a 115 degree bend onto an arena surrounded by equally-spaced
white poles, one of which was the target pole. The task was to go to the
target pole (colored red during training, white during test) which
remained the same throughout the entire experiment. The environment also
contained three rectangular objects inside the arena (local landmarks) and
three larger ones outside the arena (global landmarks). For each trial one
local, one global, all local, all global, or all objects shifted 6, 12, or
18 degrees to the right or left of their original location. The subjects
were warned of this. Results showed that despite their knowledge that
objects could move, subjects relied on them as landmarks to find the
target pole. Furthermore they relied more on local objects than global
objects. These results will be contrasted with subjects' performance in an
environment without landmarks.
The lecture will take place in the
Lecture Hall, Room 203, 44 Cummington St.
on Monday, March 27, 2000
at 1:00 pm
Hosted by the
Brain and Vision Research Laboratory