In Drosophila, as in many other insects, males court- ing females vibrate their wings to produce species-specif- ic sounds (pulsatile and sinusoidal songs), which play an important role in species isolation and courting success [6, 9, 10, 27, 28]. The neuromuscular mechanisms under- lying courtship songs and a corresponding functional model were described by Ewing [7, 8]. Mapping using sexual mosaics showed that the neural networks responsi- ble for generating normal courtship sounds (the “song center”) are located in the thoracic ganglia, mainly in the ventral mesothoracic neuromer [29], while the dorsal part of the brain is involved in controlling the early stages of courting – the pursuit of females and the display of the wings to females [12, 20]. The role of the main brain cen- ters – the mushroom bodies and the central complex – in Neuroscience and Behavioral Physiology, Vol. 33, No. 1, 2003 The Role of Central Parts of the Brain in the Control of Sound Production during Courtship in Drosophila Melanogaster A. V. Popov, 1 N. A. Sitnik, 1 E. V. Savvateeva-Popova, 2 R. Wolf, 3 and M. Heisenberg 3 0097-0549/03/3301-0053$25.00 © 2003 Plenum Publishing Corporation 53 Translated from Rossiiskii Fiziologicheskii Zhurnal imeni I. M. Sechenova,Vol. 87, No. 6, pp. 779–794, June, 2001. Original article submitted August 14, 2000. The question of the roles of the two main parts of the insect brain, the mushroom bodies and the central complex, in controlling motor coordination and triggering a variety of behavioral programs, including sound production, remains controversial. With the aim of improving our understanding of this question, we studied the parameters of songs used by five-day-old males during courtship for fertilized wild-type females (Canton-S, C-S) over 5-min periods at 25°C; males were of two wild-type Drosophila melanogaster lines (Berlin and C-S). Berlin males lacking mushroom bodies because of treatment with hydroxyurea during development (chemical removal of the mushroom bodies) were used, along with two mutants with defects in the mushroom bodies (mbm 1 and mud 1 ), two mutants with defects in the central complex (ccb KS127 and cex KS181 ), and mutant cxb N71 with defects in both the mushroom bodies and the central complex. The experiments reported here showed that courtship songs in males lacking mushroom bodies were virtually identical to those of wild-type males. The main parameters of pulsatile song in mutants mbm 1 and mud 1 (interpulse interval and train duration) were insignificantly different from those of the songs of wild-type flies, though the stability of the pulse oscillator was the same. Flies of these lines were no different from wild-type flies in terms of courtship success (percentage of copulating pairs in 10-min tests). Conversely, the songs of mutants with defects in the central complex differed from those of wild-type males. Firstly, there was degradation of the stability of the pulse oscillator and interpulse inter- vals were very variable. In addition, pulses were often significantly longer and appeared multicyclic, as in the well-known cacophony mutant, while the mean train duration was significantly shorter. Males of the line cex KS181 usually courted very intensely, though abnormal sounds were generally emitted. Mutants cex KS181 and ccb KS127 were significantly less successful in courtship than wild-type flies. These data show that the central complex appears to play a very important role in controlling song, while the mush- room bodies are not related to this function. KEY WORDS: Drosophila, courtship behavior, sound production, mushroom bodies, central complex, brain. 1 I. M. Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, 44 M. Torez Prospekt, 194223 St. Petersburg, Russia. 2 I. P. Pavlov Institute of Physiology, Russian Academy of Sciences, 6 Makarov Bank, 199034 St. Petersburg, Russia. 3 Department of Genetics, Theodor Boveri Institute of Bio- logical Sciences (Biozentrum), Am Hubland, 97074 Würzburg Germany.