The relative lability of mobile and stationary components in a visual-motor adaptation task

The results of previous studies of intermanual transfer of prism adaptation may have been biased because the arm was mobile during training, rather than for instance the head. It was hypothesized that adaptation will be more associated with a joint when it is mobile rather than stationary. Intermanual transfer when arm was mobile and head stationary was compared with that when head was mobile and arm stationary. Also measured was the adaptation persisting when the mobile part in training was stationary in testing. The results showed, against the original hypothesis, that adaptation tends to be associated with a stationary joint. This fits in with evidence that there is greater position uncertainty in a stationary joint and that this is associated with adaptability.