TRACING THE MEMORY MECHANISMS IN THE SONG ACQUISITION OF NIGHTINGALES

The song acquisition system of oscines shows adaptive specialization for selective, high capacity and long-term storage of signal patterns to which a bird normally is exposed early in life. This report reviews studies designed to examine the mechanisms involved in memory formation and storage of songs. The experiments were conducted on nightingales (Lascinia megarhynchos), a species renowned for its vocal 'virtuosity' and the development of large song-type repertoires by precise imitation of heard song models. In the analyses the relationships between variables of exposure to learning stimuli and variables of singing performances were examined on different hierarchy levels of performance organization. Particular focus was on the characteristics of reproduction of order information encoded in a series of song models presented in a play-back design. The results allowed to distinguish between an exposure-related and a self-induced memory organization. The characteristics of the latter, in particular, proposed a series of experiments set out to examine the mechanisms mediating the acquisition and storage of information.