Biology Reference
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never able to decide what the relation was. His insistence upon
the hopeless attempt to make a single kinetic system explain
such utterly divergent adaptations as that from bleaching and that
from backgrounds has thrown the whole subject into a lasting
confusion.
Not only the kind of mechanism of bleaching and background
adaptation, but also their sites of adaptation were assumed to be
different. Thus, Rushton (
1972
) had come to suspect that bleaching
adaptation was mainly sensitivity regulation in the receptors, while
background adaptation was mainly a signal scaling mechanism
proximal to the receptors - possibly situated in the horizontal cells.
He found supporting evidence in the immense number of receptor-
bipolar junctions these cells connected to. On p. 505 Rushton
(
1972
) made his position clear, 'For eight years I have hoped that the
horizontal cells are Fechner scalors, and I still hope so.'
