Using voltage clamp recordings of thalamic neurons in slices, we have measured the kinetics of the low-threshold Ca2+ current, IT in both monkey and ferret (Carden et al, SFN abstr, 2003). The kinetics of IT in the two species are similar but not identical, leading to differences in burst activity. Moreover, these differences may represent modulatory influences on IT that can affect biophysical channel properties. Using our in vitro data, we have constructed integrate-and-fire-or-burst (IFB) models of thalamic responses (Fisher et al, SFN abstr, 2003) that incorporate the key kinetic parameters of the native IT of the macaque for comparison to a similar model equipped with parameters derived from our recordings in ferret under the same conditions. Here we studied the response of the models when driven with sinusoidal current and, in separate experiments, with random stimuli composed of “colored” noise (i.e., correlation time τcor > 0). We found that burst activity varied across the two models. Isolated bur...