  We propose a mechanism for testing the theory of collapse models such as
continuous spontaneous localization (CSL) by examining the parametric heating
rate of a trapped nanosphere. The random localizations of the centre-of-mass
for a given particle predicted by the CSL model can be understood as a
stochastic force embodying a source of heating for the nanosphere. We show that
by utilising a Paul trap to levitate the particle and optical cooling, it is
possible to reduce environmental decoherence to such a level that CSL dominates
the dynamics and contributes the main source of heating. We show that this
approach allows measurements to be made on the timescale of seconds, and that
the free parameter $\lambda_{\rm CSL}$ which characterises the model ought to
be testable to values as low as $10^{-12}$ Hz.
