Drosophila Melanogaster Tone Interval and Substrate Discrimination Employing Classical Conditioning
Brianna D’Elia, Alexa Decker, Amanda Disney, Claudia Ko, Julian Paul Keenan

It is speculated that perceiving or differentiating two combined tones (i.e., an interval) is not an evolutionarily evolved trait in Drosophila melanogaster. However, in humans and other advanced mammals, recognizing two simultaneously presented auditory stimuli is often thought to be a critical component of verbal linguistic communication. It is not known when tone interval differentiation evolved (or if there has been independent evolution) or if genes exist in insects that might translate into complex interval recognition abilities. Here, we examined Drosophila melanogaster to determine if they are able to discriminate between a consonant and dissonant tone paired with different substrates employing a classical conditioning paradigm. Previous research has indicated that sucrose is an unconditioned stimulus (UCS+) that elicits a positive (e.g., approach) response. Conversely, caffeine (UCS-) elicits a negative response. Following 2 conditioning trials of 5 minutes each, the organisms were tested for successful learning. White noise was included as a control.A significant interaction was discovered such that successful conditioning occurred when caffeine was paired with a dissonant interval and sucrose was paired with a consonant interval (but only larvae). Furthermore, conditioning in larvae had a slight but significant correlation in adults. Further research should focus on molecular genetic mechanisms and the role of individual differences in genomics.

Full Text: PDF     DOI: 10.15640/jpbs.v3n2a5