Background. Sound symbolism (SS) refers to the direct association between the sound and the meaning of a word. The results of cross-linguistic research prove that SS is universal for different languages and cultures. Thirty percent of all natural languages consist of SS words. But despite the large number of psychosemantic studies which have been conducted, the cognitive mechanisms of the perception of SS words still remain unclear. Objective. The aim of this study was to determine how Russian-speaking subjects perceive visually presented English and Russian words, as measured by the Lexical decision method. Design. The study sample consisted of 148 subjects of ages ranging from 13 to 78. The study was conducted in two stages. During the first stage, the perception of visually-presented English SS words by Russian learners of English, with three different levels of language proficiency, was studied. During the second stage, the perception of visually-presented Russian SS words by Russian native speakers from three different age groups was studied. The stimuli material was selected according to the following criteria: 1) ach word was monosyllabic; 2) Each SS word corresponded to a single arbitrary (non-SS) word of the same pronunciation type; and 3) Each word corresponded to a non-word, formed from it by replacing letters according to the phonotactic rules of English and Russian. At each stage of the study, each subject was given 80 stimuli consisting of 20 SS words, 20 non-SS words, and 40 non-words. An analysis of contingency tables (Chi-square test), comparison of averages (Student's t-test), and analyses of variances (ANOVA) were applied to the data. Results. The visually-presented SS words were identified more slowly and with more errors than the non-SS words, regardless of the language (Russian or English), the subjects' age, and their English language proficiency. Conclusions. The observed delay effect in the cognitive processing of visually- presented SS words is due to the cognitive complexity of the task, which leads to the activation of cross-modal interaction system, besides, interfering systems of information processing are assumed to exist.