Biology Reference
In-Depth Information
(Y-B) and white-black (W-S) opponent processes take place. To explain
the variety of colour experiences, G. E. Müller needed yet another
level of complexity. Thus, in addition to the opponent processes in
the see-substances, he introduced red-green (r-g) and yellow-blue (y-b)
opponent processes in a red-green (r-g) and yellow-blue (y-b) substance
located in the outer segments of the cones.
5.2.6 The P1 system
As illustrated in
Fig. 5.1
, the P1 process activates both the red-green
and yellow-blue substances in the outer segment of the cones.
Thus, P1 activates the r-process in the red-green substance and also,
weakly, the y-process in the yellow-blue substance. The r-process,
then, activates red (R)-, yellow (Y)- and white (W)-related processes
in the see-substances, while the y-process activates yellow (Y)-, green
(G)- and white (W)-related processes.
5.2.7 The P2 system
The P2 process first activates the g-process in the red-green substance
in the outer segment of the cones and the y-process in the yellow-blue
substance. Then, the g-process activates the green (G)-, blue (B)- and
black (S)-related processes in the see-substances, while the y-process
activates the yellow (Y)-, green (G)- and white (W)-related processes
like the y-process of P1.
5.2.8 The P3 system
Finally, the P3 process first activates the b-process in the yellow-blue
substance in the outer segment of the cones and then the blue (B)-, red
(R)- and black (S)-related processes in the see-substances. In addition
to this complex processing, P1, P2 and P3 all directly activate the
white (W)-related process.
Both the processes in the red-green and yellow-blue substances
in the outer segment
of the cone receptors and the processes in the
see-substances were assumed to be of an antagonistic nature and to
closely follow the same reaction pattern. They may, therefore, all be
