In most moving animals and robots, locomotor control and postural stability depend on sensory systems to provide state change information. Besides proprioceptive and inertial sensing, vision proved to be essential for estimating state changes in the low and intermediate dynamic range.
Flying insects rely heavily on vision for attitude control and stabilization. Studies on these insects and specifically the dipteran flies give us some insight on how animals employ neuronal ‘matched filters’ to extract information from wide-field shift of scenes known as the optic flow, and use such information to control their states of motion. However, most studies carried out so far have been on the female individuals of one species. To see whether there are general functional principles among the dipteran flies, sensorimotor systems of other species need to be studied.
This thesis focuses on the question of how visual motion information in different fly species is processed and ultimately supports flight stability. To answer this question, I assembled the receptive fields of four types of neurons in the insects’ optic lobe by means of extracellular recording, extracted the preferred motion components from the neurons’ receptive field, then compared the components across 5 species. The neurons’ temporal responding properties were also recorded and compared across species. From comparing the results, the general and species-specific features were identified.
This work provides useful data to test the generality of the Mode Sensing Hypothesis, as well as complementing studies on insect motor systems.