10 odors were presented to three different groups of 20 subjects each
(10 men and 10 women) to investigate the relationships among encoding
conditions and both immediate and delayed incidental recognition of od
ors. Subjects who were not told to memorize the material and not infor
med of the final recognition test had to evaluate the intensity of eac
h odor (Task 1), to judge the similarity of each odor to mint (Task 2)
, or to score each odor for pleasantness and sourness (Task 3). The su
bjects had to recognize test odors, represented one at a time, togethe
r with some distractors, immediately thereafter (Immediate Test) and o
ne week later (Delayed Test). Task 1 and Task 2 produced better perfor
mances (77% and 75% of items recognized immediately; 66% and 69% recog
nized after a week) than Task 1. The performance on Task 3, more conce
ptually driven, was the worst, both immediately (67%) and a week later
(52%). Sex and task reliably interacted: women performed better than
men on Tasks 1 and 3, men on Task 2. Accuracy did not vary by task but
by test time (immediate or delayed). Better performance on Tasks 1 an
d 2 may depend not only on more effective storage but also on the bett
er fit between the task and the test.