Photodarkening, or the shift of the optical absorption edge to smaller energies after excitation with light whose energy is near that of the optical band edge, has been studied in the chalcogenide glasses for many years. Authors have conducted high field NMR studies at 17 T and NQR studies of 75As in glassy As2S3. Authors have compared the 75As NMR and NQR lineshapes in glassy As2S3 and As2O3 before and after irradiation. An increase in the asymmetry parameter would have implied an increase in the departure from cylindrical symmetry in the bonding at the As pyramidal sites. The null result reported here is inconsistent with microscopic models of photodarkening that involve switching of large numbers of As chalcogen bonds. 16 refs.