An imaging member, such as a negative-working printing plate or on-press cylinder, has an imaging layer comprised of a thermally sensitive compound and a photothermal conversion material. The thermally sensitive compound comprises a heat-activatable bisulfite adduct and can be a polymer or a small molecule compound. In the imaging member, the thermally sensitive compound reacts to provide increased hydrophobicity in areas exposed to energy that provides or generates heat. The imaging layer is considered "switchable" and can be used to provide a lithographic printing image without traditional alkaline wet processing.