Dynamic resistivity measurements were conducted on copper wires which were rapidly deformed in the plastic range. Of major interest were the instantaneous changes in the resistivity of the metal immediately after the straining was abruptly halted. Records of resistivity change versus time were obtained at three different temperatures. At each temperature, tests were conducted for varying values of strain in an attempt to deduce any dependence of the resistivity change on strain. It was observed that at each temperature, the resistivity decreased rapidly from a maximum value to an equilibrium value. The only useable results were those obtained at room temperature, and these are interpreted in terms of the diffusion of point imperfections to sinks, where they are annihilated.