Differential neuronal responses to indentations at different speeds. Time series of extracellular potentials of a cortical neuron, in which soma was indented with a 5 µm bead. The solid line at the top represents the vertical movement of AFM cantilever and bead at 10 µm s –1 (black) and 0.1 µm s –1 (blue). Number of action potentials evoked through 10 µm s –1 and 0.1 µm s –1 indentations were compared using a two-tailed Mann–Whitney U -test. The P value of 0.004 ( n = 8 individual neurons) suggests that neurons can differentiate indentation speeds.
