Apparatuses and methods for using proximal probes. A method includes measuring motion of an oscillating probe, producing a signal indicative of motion of the oscillating probe, and filtering the signal indicative of motion of the oscillating probe. In one embodiment, filtering includes performing signal decomposition to produce a filtered signal. In another form, filtering includes performing a Fourier transform, comb filtering in the frequency domain, and performing an inverse Fourier transform to produce a filtered signal. In another embodiment, filtering includes amplifying specific frequencies of the signal indicative of motion of the oscillating probe. Apparatuses according to the present invention are also provided.