BRAIN ASIMMETRY HAS A ROLE IN LONG TERM
MEMORY
A small proportion of
wild-type Drosophila melanogaster flies has a symmetrical brain which shows two
symmetrical structure for both sides, involved in rudimentary cognitive
processes, instead of a single one as in the normal type. Alberto Pascual (preat@iaf.cnrs-gif.fr) and his colleagues (Brief Communication in Nature 427, 605 –
606, 12 February 2004) studied anatomical-functional correlation of the
difference by comparing the two Drosophila’s type.
The asymmetrical
positioning of neural structures on the left or right side of the vertebrate
and invertebrate brain has been related to laterality, which is associated with
cognitive skills. Until now, this assumption has not been illustrated by strong
experimental demonstrations. In the last 12 February communication to Nature,
Pascual reports that the symmetrical Drosophila lacks a normal long-term
memory, although its short term memory is intact. The authors speculate that
brain asymmetry may be required for generating or retrieving long term memory.