This study aims to resolve the ongoing debate about sensory modality embodiment found in linguistic synesthesia by proposing an empirical model: Perceived Strength of Embodiment (PSE). The perceived strength of embodiment for sensory adjectives is measured based on the sensory ratings of the adjectives in the five sensory modalities, while the perceived strength of embodiment for each sensory modality is calculated based on the PSE of all adjectives according to their dominant modalities. PSE is designed to address a salient dilemma in the widely-accepted modality-based embodiment asymmetry: that is, such asymmetry fails to predict the directionality behaviors between sensory words because each sensory word is typically associated with more than one modality, and each may have different strengths of association. Based on an analysis of sensory adjectives, we find that a lexical concept-based embodiment asymmetry better explains the data than a modality-based embodiment asymmetry and, additionally, the lexical concept-based account is supported by Mandarin synesthetic compound adjective data. In sum, this paper argues that the PSE model is an empirical approach to measuring the degree of embodiment which furthers the understanding of the role of embodiment in the linguistic conceptualization of sensory perceptions.