Multimodal data integration is increasingly central to neuroscience and perception science, where heterogeneous signals such as behavioral responses, sensory inputs, electrophysiological recordings, neuroimaging measurements, and computational representations must be jointly interpreted. Based on the realistic background, there is a core theoretical problem that needs further research: under what heterogeneous processing conditions does enhanced multimodal information utilization produce meaningful gains, when does it become strategically necessary, and when does it generate only limited benefits relative to its cost? To clarify this core problem, this study develops a conceptual game-theoretic framework in which information utilization is treated not as a universally beneficial technical upgrade, but as a conditional strategic choice shaped by signal heterogeneity, information asymmetry, integration cost, and differential decision influence across actors. Within this framework, we compare three endogenous strategic profiles—no enhanced information utilization, unilateral information enhancement, and bilateral information enhancement—across multiple heterogeneous environments. The analysis results show that the value of multimodal information utilization is fundamentally environment-dependent. In highly homogeneous environments, additional information processing yields little marginal benefit and is therefore not sustained in equilibrium. In moderately heterogeneous environments, however, multimodal information utilization emerges as a strategically necessary response because it reduces mismatch, improves alignment, and stabilizes decision outcomes. In more asymmetric environments, stronger decision agents capture a disproportionate share of the gains from enhanced information utilization and increasingly rely on differentiated strategic responses, whereas weaker agents adopt more defensive and uniform strategies. In highly dominated environments, the marginal value of additional information utilization declines again because structural dominance itself already secures most attainable advantages. These findings contribute to multimodal neuroscience and perception science by clarifying that the consequences of information utilization depend not only on fusion efficiency, but also on environmental structure, asymmetry, and the distribution of strategic power.

