Method
Note in Figure 2 that a taste memory decrement is already apparent at the 1.a-min interval. We attempted to measure more precisely the time course of the memory decay by having 20 additional
subjects taste 2.0 ml of a 15% sucrose solution (standard) followed by 2.0 ml of a 15% sucrose solution (comparison) at delays of 15 sec (n = 10) and 45 sec (n = 10). The instructions to the subjects were identical to those used in Experiment 1 (i.e., the subjects were instructed that the comparison stimulus could be more, less, or equally intense). In addition, the subjects were
asked to rate the intensity of the comparison stimulus, relative to that of the standard, by drawing a clock hand on a clock face. This magnitude estimation procedure assigned a score of 100 (positioned at 12 o'clock) for a judgment of equality of the standard and the comparison stimulus. When the comparison stimulus was judged to be "less sweet," the clock hand could be placed anywhere from 0 to 100 units (6 to 12 o'clock); when judged to be "less sweet," it could be placed anywhere from 100 to 200 units (6 o'clock) for judgments of "more sweet." The subjects ate a saltine cracker and rinsed with tap water between the two sucrose tastes.
Results
The results replicated the findings in Experiment in that 7 of 10 subjects of each group reported the second stimulus as being sweeter, according to this magnitude estimation procedure. We found no significant differences between the two delay conditions: The average setting for the IS-sec delay was 114 units (mean standard error = 8.2), and the average for the 45-sec delay was 120 units (mean standard error = 9.3)