Model for Recognition

Benjamin Navia (Biology)

Testing a model for recognition in the auditory system of the cricket Acheta domesticus

Invertebrates are good models to help us understand the underlying neuronal mechanisms that control behavior. The cricket is one such model. Advantages to using this model includes the complex processes it performs (sound localization and recognition), the relatively small number of neurons in its auditory system, the access to the neurons and the fact that its behavior can be quantified. Early descriptions suggested that the response of the female to the calling song of the male was fixed and consistent. Recent findings have demonstrated that the females' responses are more variable than the early descriptions suggested. This poses a follow up question regarding the underlying neuronal mechanisms in terms of its ability to control such variable responses. An approach to test this model is to manipulate conditions such that they cause changes at the behavioral level, quantify these changes and then evaluate how these manipulations modify the underlying neuronal circuits controlling such response. A neural circuit in the prothoracic ganglion has been suggested to be involved in sound recognition. The L3 auditory interneuron is one component in this prothoracic circuit which has been proposed to have a major role in sound localization and recognition. A circuit model that attempts to help us understand the function of the auditory circuit in the prothoracic ganglion of the cricket has been developed (see fig. 1 below), and this grant seeks funding to evaluate such model. Pharmacological manipulations with agents such as histamine and antihistamine will help us evaluate the role of this neuromodulator in the circuit.