More recent research, 
however, may shed some light 
on adaptation to optical 
inversion and reversal and on 
the ambiguities in both 
Stratton’s and Kohler’s reports. 
Charles S. Harris, at the 
University of Pennsylvania and 
Bell Laboratories, has 
confirmed Stratton’s report 
that, when optical devices 
create a discrepancy between 
the visually perceived 
locations of body parts and 
their felt locations as given by 
the proprioceptive, or position 
sense, the position sense is 
actually recalibrated to 
conform with the visual 
information. Not only does 
visual capture occur, but with 
longer exposure to a more 
extreme discrepancy--mirror 
reversal of the image of the 
observer’s moving hand--
proprioceptive perception 
ultimately is drawn into line 
with the reversed visual 
perception, even though at first 
the observer is acutely aware 
that the seen direction of hand 
movement is the opposite of the 
felt direction. This 
recalibration of touch and 
sense of position persists even 
when the distorted visual 
information that caused it is no 
longer present, as was 
mentioned in Chapter 5.

    Harris argues that analogous 
changes in position sense 
underlie Stratton’s and 
Kohler’s adaptation and make 
comprehensible their 
otherwise puzzling reports. For 
example, Stratton says that 
when he first donned inverting 
lenses, "... the parts of my body 
were felt to lie where they 
would have appeared had the 
instrument been removed; they 
were seen to be in another 
position. But the older tactual 
... localization was still the 
real localization." As the 
experiment progressed, 
however, "... the limbs began 
actually to feel in the place 
where the new visual 
perception reported them to 
be."