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Abstract

The consequences of an action usually occur immediately. One of the more important
ramifications of this is that delaying visual feedback greatly impairs performance on a
wide range of tasks. Cunningham et al. (ARVO 1999) have demonstrated that with practice,
humans can perform equally well with delayed and immediate visual feedback on a
simple obstacle avoidance task with abstract stimuli. Here, we examine the effects of
training in more detail under more realistic conditions.
Naive volunteers maneuvered a virtual car along a convoluted path in a high-fidelity virtual
environment, which was projected onto a 180 deg. screen. Subjects drove at a constant
speed, steering with a forced-feedback steering wheel. In Exp. 1, subjects were presented
with 7 speeds in random order 5 times, using immediate visual feedback and a
single path. Subsequently, subjects trained with a 280 ms delay, and then were presented
with 5 trials at the fastest speed they had successfully completed in the first section. In
Exp. 2, subjects were given 15 trials of practice using immediate feedback. Following
this, subjects’ performance with 5 paths at 3 speeds was measured, then they trained on a
new path, and finally they were presented with 5 new paths at the 3 speeds.
In both experiments, training with delayed feedback improved performance accuracy
with delayed feedback, and seemed to reduce the perceptual magnitude of the delay. In
Exp. 1, the training also lowered performance with immediate feedback. In Exp. 2, the
improved performance generalized to novel paths.
These results are the main hallmarks for sensorimotor adaptation, and suggest that
humans can adapt to intersensory temporal differences. Regardless of the underlying
mechanism, however, it is clear that accurate control of vehicles at high speeds with
delayed feedback can be learned.