  The impact of the short-range $N\Delta$ interaction on the pion
photoproduction processes off the deuteron in the $\Delta$-resonance region is
studied in the framework of recently proposed dressed-bag model. A common
dressing procedure for bare three- and six-quark states is used to describe
both the pion decay widths of baryon resonances and the effective $NN$ (or
  $N\Delta$) interaction at short ranges related to the inner dressed-bag
states. It is shown that the effect of short-range $N\Delta$ interaction for
the forward-angle $\pi^\mathrm{o}$ photoproduction off the deuteron cannot be
neglected. The prospects for further development of the model to describe the
short-range $NN$ (or $N\Delta$) correlations in the lightest nuclei are
discussed.
