Basic NeuroscienceA fully automated Drosophila olfactory classical conditioning and testing system for behavioral learning and memory assessment

- Fully automated system of Drosophila olfactory associative conditioning and testing.
- Odorant levels, airflow and electrical shock delivery all automatically monitored.
- Control software allows operator-input variables to define experimental parameters.
- System allows Drosophila learning, short-term memory and long-term memory assays.
- Accurate and efficient behavioral learning/memory analyses with a minimum of labor.

BackgroundAversive olfactory classical conditioning has been the standard method to assess Drosophila learning and memory behavior for decades, yet training and testing are conducted manually under exceedingly labor-intensive conditions. To overcome this severe limitation, a fully automated, inexpensive system has been developed, which allows accurate and efficient Pavlovian associative learning/memory analyses for high-throughput pharmacological and genetic studies.New methodThe automated system employs a linear actuator coupled to an odorant T-maze with airflow-mediated transfer of animals between training and testing stages. Odorant, airflow and electrical shock delivery are automatically administered and monitored during training trials. Control software allows operator-input variables to define parameters of Drosophila learning, short-term memory and long-term memory assays.ResultsThe approach allows accurate learning/memory determinations with operational fail-safes. Automated learning indices (immediately post-training) and memory indices (after 24 h) are comparable to traditional manual experiments, while minimizing experimenter involvement.Comparison with existing methodsThe automated system provides vast improvements over labor-intensive manual approaches with no experimenter involvement required during either training or testing phases. It provides quality control tracking of airflow rates, odorant delivery and electrical shock treatments, and an expanded platform for high-throughput studies of combinational drug tests and genetic screens. The design uses inexpensive hardware and software for a total cost of ∼$500US, making it affordable to a wide range of investigators.ConclusionsThis study demonstrates the design, construction and testing of a fully automated Drosophila olfactory classical association apparatus to provide low-labor, high-fidelity, quality-monitored, high-throughput and inexpensive learning and memory behavioral assays.