The behavior of periods of motives under twisting by Artin motives was studied in depth by Blasius. Building on Deligne’s conjecture concerning the critical values of motivic L-functions, Blasius proposed a refined conjecture on the algebraicity of the critical values of twisted motivic L-functions, as well as its automorphic analogue in the setting of standard L-functions of algebraic cuspidal automorphic representations twisted by Artin representations. In this talk, we present results establishing new cases of the automorphic analogue under suitable regularity assumptions.