|We study the dynamics of active region moss using IRIS. Active region moss is well studied in higher resolution using Hi-C at 195 A. Hi-C has only coronal channel. We conjectured that high frequency oscillations are present at moss regions (Pant et al, 2015). However imaging only can not distinguish between waves or flows. IRIS gives us unique opportunity to study high frequency dynamics due to its large spatial and temporal resolution. Spectral information combined with imaging may shed light on such high frequency phenomena. We find high frequency at several locations along the spectral slit. Some initial spectroscopy and imaging results will be presented in this presentation.