Token Homogenization under Positional Bias

Abstract: This paper investigates token homogenization - the convergence of token representations toward uniformity across transformer layers and its relationship to positional bias in LLMs. We empirically examine whether homogenization occurs and how positional bias amplifies this effect. Through layer-wise similarity analysis and controlled experiments, we demonstrate that tokens systematically lose distinctiveness during processing, particularly when biased toward extremal positions. Our findings confirm both the existence of homogenization and its dependence on positional attention mechanisms.