Psikoloji Çalışmaları; 1966;4():85-120
Dokunma Tenzihlerinin Lokasyonu ve Mümaresenin Tesiri
Y Özakpınar
İstanbul Üniversitesi, İstanbul
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Tactile Localization on Toes
The process of tactile localization on toes was investigated in
normal subjects. The stimulation involved in different experimental
sessions a single toe, two toes simultaneously, and two or three toes
successively. The subjects reported the stimulated toe or toes according
to the agreed number code. The effects of practice with verbal
and the tactual knowledge of results were also studied.
The order of the accuracy of localization was 1,5,2,3,4, when
big toe is 1.Majority of errors occured on 2 and 3 with little difference
between them. On the middle three toes 70 per cent of the errors is
in the direction of little toe. Usually an erroris influenced by a previous
one resulting in progressive shifts This is so strong a tendency
that some subjects felt that there should have been a sixth toe after
the little toe. Subjects found difficulty in feeling the middle three toes
distinctively. Tactual experience of a great gap between big toe and
second toe leads subjects to identify second toe as third and this
starts off the chain of errors on middle toes. udgments on single stimulations are not independent of each other.
They are not based purely on the immediate sensations but in
every instance they are related to previous stimulations. It appears
that the localization process involves more than sensory experience,
it draws upon reasoning through verbal knowledge of results. This
often leads to localizations which are different from what would be
suggested by immediate sensory experience alone. It is very likely
that this is the cause of the striking fluctuations in the practice curves
of individual toes though there is slow but continuous over-all
improvement. The conflict between feeling and reasoned conviction
resulted in some instances in collapse of judgment. Tactual knowledge
of results could be used more effectively and this kind of conflict did
not arise. It led to more stable improvement than when knowledge of
results was merely verbal.
In experiments where more than one toe were stimulated successively,
it was noted that right-left orientation of each stimulation could
be preserved even when all the three simulations were localized incorrectly.
The precarious character of the improvement in the accuracy of
localization through practice with verbal knowledge of results could
be better understood by the results obtained from experiments with
wrong knowledge of results. Subjects could 'learn' to utilize this kind
of knowledge to the consistent detriment of their localizations, showing
an improvement in reverse.