The interaction mechanism involving fermions and lochons (local charged bosons) located at polarizable dielectric regions in the layered curprate systems is discussed in the context of the pairing symmetry, the appearance of the resonance peak and the pseudogap which is seen above T_c. It is found that the mechanism allows both a and d waves and the dominance of one or the other depends on the relative values of the Fermi energy and the nearest neighbor hopping integral. The model accounts for the pseudogap and the resonance peak is identified with the local pair fluctuation state. The mechanism, along with a weak phonon contribution, emerges as an acceptable model for HTSC.
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