S. Bhagavan et Bh. Smith, OLFACTORY CONDITIONING IN THE HONEY-BEE, APIS-MELLIFERA - EFFECTS OF ODOR INTENSITY, Physiology & behavior, 61(1), 1997, pp. 107-117
Any odor-guided behavior might require generalization and/or discrimin
ation over a wide range of odorant intensities. Proboscis extension co
nditioning (PEC) and electroantennogram (EAG) assays were used to inve
stigate stimulus-intensity dynamics during olfactory processing in the
honey bee. Experiments that tested generalization involved conditioni
ng to one odorant concentration and either testing with a different od
orant or with different concentrations of the same odorant. At low tra
ining concentrations, responses to either a novel odorant or to higher
concentrations of the same odorant resulted in strong generalization.
At higher training concentrations, significantly less generalization
was observed to a novel odorant or to lower concentrations of the same
odor. EAG analyses indicate that asymmetric generalization could aris
e due to long-term adaptation of peripheral receptor neurons. Discrimi
nation experiments showed that relatively higher odorant concentration
s associated with an appetitive reinforcer could usually be discrimina
ted from a lower concentration that was associated with punishment, bu
t not vice versa. Although sensory modulation in peripheral (sensory)
processes might be sufficient to account for discrimination of a high
from a low concentration, discrimination of low from high concentratio
ns point to the involvement of central processes. Copyright (C) 1996 E
lsevier Science Inc.