j *@ - Sociedade Brasileira de Psicologia

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EXPEkIMENG LDESIGN
The present investigation is based on the olfactory classical conditioning
paradigm . Floral odors such as ketones o! critral e .g. gernniol, carnation, are applied as
conditioned stimuli (CS) and sucrose solution (30 micol, 1.5 M) is tksed as an
unconditioned stimulus (US) in delayed conditioning. M a conditioned response (CR),
proboscis extension is recorded digitally i.e . proboscis reflex yes or no. The interstimulus
interval (ISI) is very crudal. Optimnl ISI is 2-3 seionds (6). Under these
conditions, proboscis reflex as the conditioned response (CR) reaches a level of more
'lun 7(N , even after a single learning trial (7 , 8 , 9, 10). To examine the effects of
nmines on mem ory storage and retrieval, the test amine, or bee ringer as control, is
presme. injected, either globaly (0.5 n1) to alow diffusion to a responsive like, or
localy (2-10 1) in specific areas of the brain to minimize peripheral difusion. In the
storage test, the drug is injected 5-20 min before a single learning trial, while in the
retrieval test tle injection folows the conditioning 30-90 min later. '
One of the reasons why one generally initially starts with the retrieval test
and then the storage test is that since the former test is reversible the o/timnl time for
the maximl'm effect of the test substance can be determined.
Animnls showing spontaneous readions during the learning trial are excluded
from the experiments. In the case of 5-HT exm riments, double-blind test were
conduded.
statkstics: 'rlte kolomogorof-smirnoff cl# -test is used to test the homogeneity
of the experimental and control poups.
RESULTS Ae DB CUO ION
Effeds of biogenic nmlnes oa memèry stomge and retrieval
DA: evokes a reduction of the CR occm rence in the retrieul test, when
globaly injected (03 nl 1 x10-5 M) into the re#on of the median ocelar trad (11).
ln the storage test, this test solution does not show any differences to the control
p oup. Thus DA selectively influences memory retrieval.
NA: in comparkson to DA, NA blocks the CR in b0th memory phnmes when
globaly injected. However, when lormly injeded (1 x10 d M, 2-3 n1) into both alphalobes,
an enbnniement of the CR is monitored if the bees elidt a very 1ow rate of
learning (12). hi contrast, no influence upon memory storage Lq observed when NA is
localy Kjected hzto the Pedunculi or Antermal lobes of tlp deutùcerebrlvm (13). The
signilrmnce of the reversal of the inluenœ of NA (global as compared to local hjection)
is not tmderstood at present.
5-HT: When 5-HT is globaly injected, a blocking of the CR occurs, esm daly