The parametrization of dynamic and thermal action of internal gravity waves (IGWs) on the general circulation of the middle atmosphere is modified to take into account latitudinal inhomogeneities in the distribution of wave intensity in the lower atmosphere. The sensitivity of the COMMA-SPBU numerical model of general circulation to observed inhomogeneities of wave source intensities produced by the global distributions of orography, convective processes, and jet flows in the troposphere, as well as their seasonal changes, is studied. Typical distributions of the latitudinal structure of IGW intensity at a height of about 30 km are specified in accordance with data of ground-based and satellite observations. Taking into account the latitudinal inhomogeneity of IGW sources weakens westerlies and enhances easterlies in the stratosphere and mesosphere of the winter and summer hemispheres, respectively, as well as enhances zonal winds of opposite directions above the mesopause. An analysis of model calculations for different latitude distributions of the IGW intensity in the stratosphere shows that the general structure of the distribution of zonal mean wind is most sensitive to changes in wave sources at middle latitudes.