Testing a model for recognition in the auditory system of the cricket
Invertebrates are commonly used as model systems to study how small groups of nerve cells control behavior. The cricket model has several advantages: it is small, it has relatively few neurons in its brain, and it performs complex processes, such as sound recognition and localization. An early paradigm suggested that adult female crickets respond in a stereotyped way to the stereotyped calling songs of males. Our lab’s more recent findings indicate the calls of males are much more variable and may contain more information than species identity (i.e. fitness). Further, the females responses are more variable than the early descriptions suggested. We have developed a model circuit for the auditory neurons involved in the recognition process. Our model includes modulation to account for variability described to date.
One way to test this model is to find yet unknown perturbations, which modulate the phonotactic behavior. Once these effects on behavior are documented, we can ask if the neural circuit in the prothoracic ganglion, which we have proposed to be involved in recognition, is capable of processing this newly described variability. This is a long-term project, which will take 2-3 years to complete. This proposal seeks funding to evaluate three new perturbations of this system. Phase 1 will evaluate the effects of circadian rhythms on phonotaxis. Phase 2 will evaluate the role of previous experience on phonotaxis. Phase 3 will evaluate pharmacological manipulations with histamine. Subsequent evaluations and grants will evaluate whether the model circuit is sufficient to processing these effects/perturbations or if other neural elements need to be added.