|
| |
|
|
|
|
||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | ||||
|
Fig. 2. Conditioned taste aversion following a one-trial conditioning procedure in
snails using sucrose as the conditioned stimulus (CS) and KCl as the
unconditioned stimulus (US). (A) The ratio of good and poor performers is
assessed by their response to the CS following the one-trial conditioning
procedure. We defined good performers as those snails that significantly
reduced their response to the CS following the one-trial conditioning
procedure. This meant that good performers reduced the number of bites
min–1 in response to the CS from a level of approximately 17
in the pre-test to between 0 and 1 in the post-test session. In poor
performers, however, there was no significant difference in the response to
the CS in the post-test session compared to the pre-test session. Thus, in
each session snails responded to the CS with approximately 17 bites
min–1. We found that 21 of 50 snails could be classified as
good performers. That is, about 40% of snails acquired conditioned taste
aversion (CTA). (B) The persistence of memory following the one-trial
conditioning procedure. The numbers of snails at the pre-test were as follows:
50 for naive snails (open triangles), 50 for backward-conditioning snails
(open squares), 21 for good performers (solid circles) and 29 for poor
performers (open circles). All values are means ± s.e.m. The
x-axis is expressed in a logarithmic scale. The difference between
the feeding response of the good performers and that of the poor performers
and control snails was maintained for at least 7 days at *P<0.01
(one-way ANOVA followed by the post-hoc Scheffé's test). The
numbers of good performers and poor performers became 15 and 23, respectively,
at 7 day because some snails withdrew their body into the shell or had
died.
|
