Increase of learning abilities and maturation of the vertical lobe complex during postembryonic development in the cuttlefish, Sepia.

When shown prawns in a glass tube, cuttlefish quickly learn to inhibit their predatory behavior. By using a visual learning paradigm, we studied training and retention performances of cuttlefish aged from 8 to 90 days. We found an improvement in the acquisition of learning abilities during the first 2 months of life as well as an increase of 24-hr retention performance between 30 and 90 days of age. Using morphometric measurements of different lobes of the central nervous system, we correlated the emergence of these learning abilities with the postembryonic development of related nervous structures. Our results show that only the growth of the superior frontal and vertical lobes appears to be significantly correlated with the improvement of learning and long-term retention performances. Thus, as found in earlier data collected in Octopus, the vertical lobe complex of the cuttlefish seems to be involved in these learning processes. Copyright 2001 John Wiley & Sons, Inc.