  We propose deformations of inherent structures as a suitable tool for
detecting structural changes underlying the onset of cooperativity in
supercooled liquids. The non-affine displacement (NAD) field resulting from the
applied deformation shows characteristic differences between the high
temperature liquid and supercooled state, that are typically observed in
dynamic quantities. The average magnitude of the NAD is very sensitive to
temperature changes in the supercooled regime and is found to be strongly
correlated with the inherent structure energy. In addition, the NAD field is
characterized by a correlation length that increases upon lowering the
temperature towards the supercooled regime.
