Mechanisms of Active Tactile Exploration

• Applicant: Professor Dr. Volker Dürr
• Subject Area: Cognitive, Systems and Behavioural Neurobiology
• Term: from 2007 to 2012
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 28976007

Context-sensitive adaptation of movement sequences is a core requirement for autonomous behaviour such as exploration. When walking through their natural environment, animals maintain course in unpredictable terrain, circumvent or overcome obstacles. Thus, animals perceive and integrate sensory information and adapt their movements to the immediate spatial layout of the scene. The tactile sense is very important for near-range orientation and many animals sample the space ahead during locomotion with their whiskers or antennae. The proposed project will elucidate the neuronal mechanisms underlying fast, factually mediated adaptation of walking, using a combination of kinematic analyses, electrophysiology and computer modelling. Experiments will focus on the stick insect Carausius morosus, because it shows all known aspects of tactile exploration, is an established model organism in the neurobiology of walking, and its external skeleton and stiff antenna allow for accurate motion analyses of the legs and antennae. Firstly, behavioural experiments will characterise the searching and sampling strategies of the antennae during near-range orientation in unrestrained animals. The results will explain the coordination of antennae and front legs, particularly in turning and reaching reactions. Also, they will reveal the role of the sampling strategy and tactual contact history. Secondly, electrophysiological characterisation of the neural mechanisms mediating antenna! tactile information to the front legs will reveal how normal stepping movements are modulated appropriately. Thirdly, elaboration of a neuro-mechanical model of antennae, head and front legs will allow simulation of the observed behaviour, and analysis of crucial neural network components. The model will be tested on a mobile robot with artificial feelers.

• DFG Programme: Research Grants