Partial unilateral lesions of the mushroom bodies affect olfactory learning in honeybees Apis mellifera L.
Article first published online: 18 JAN 2005
European Journal of Neuroscience
Volume 21, Issue 2, pages 477–485, January 2005
How to Cite
Komischke, B., Sandoz, J.-C., Malun, D. and Giurfa, M. (2005), Partial unilateral lesions of the mushroom bodies affect olfactory learning in honeybees Apis mellifera L. European Journal of Neuroscience, 21: 477–485. doi: 10.1111/j.1460-9568.2005.03879.x
- Issue published online: 26 JAN 2005
- Article first published online: 18 JAN 2005
- Received 12 May 2004, revised 17 November 2004, accepted 18 November 2004
- brain lesion;
- mushroom bodies;
- olfactory learning
The mushroom bodies (MBs) are central structures in the insect brain that have been associated with olfactory learning and memory. Here we used hydroxyurea (HU) to treat honeybee larvae and induce partial MB ablations at the adult stage. We studied olfactory learning in honeybees with unilateral loss of the median calyces of their MBs and compared their ability to solve different forms of olfactory discrimination. When odorants were delivered in a side-specific manner, ablated bees could not solve either discrimination of the unambiguous problem (Paradigm 1: A+, B– on one antenna, C+, D– on the other; A+B–/C+D–) whereas they could solve at least one of both discriminations of the ambiguous problem (Paradigm 2: A+B–/A–B+), namely that proposed to their intact brain side. Non-ablated bees could learn side-specific discriminations on both brain sides. When odorants were delivered simultaneously to both antennae (Paradigm 3: A+B–C+D–), HU-ablated bees learned slower than HU-normal bees. Thus, in all three paradigms, the unilateral loss of a median calyx affected olfactory learning. We propose that the MBs are required for solving elemental olfactory tasks whose complexity is increased by the number of stimuli involved and that MB ablations could have an effect on the inhibition of information exchange between brain hemispheres.