  Recent studies have revealed asymmetries between the left and right sides of
the brain in invertebrate species. Here we present a review of a series of
recent studies from our labs, aimed at tracing asymmetries at different stages
along the honeybee's (Apis mellifera) olfactory pathway. These include
estimates of the number of sensilla present on the two antennae, obtained by
scanning electron microscopy, as well as electroantennography recordings of the
left and right antennal responses to odorants. We describe investigative
studies of the antennal lobes, where multi-photon microscopy is used to search
for possible morphological asymmetries between the two brain sides. Moreover,
we report on recently published results obtained by two-photon calcium imaging
for functional mapping of the antennal lobe aimed at comparing patterns of
activity evoked by different odours. Finally, possible links to the results of
behavioural tests, measuring asymmetries in single-sided olfactory memory
recall, are discussed.
