Research in bilingualism has shown that the balance between a bilingual's two languages is rarely even and that there is something special about the mother tongue. Theories concerning separate storage of the two languages and first language primacy predict that: (1) the meanings of translation-equivalent words are not identical, and (2) the meanings in the first language are more saturated with meaning than their counterparts in the second language. This paper reports on a study designed to measure the affective meaning of translation-equivalent words both verbally and non-verbally. For the verbal measurement, twenty-two native Japanese speakers rated a set of carefully controlled words on three seven-step evaluative semantic differential scales for Japanese and English. A similar task with pictographic opposites was used for the non-verbal measurement. The study provided evidence for greater emotional meaning in the subjects of words in their mother tongue, and for a separation in cognitive storage for translation-equivalent words in the Japanese-English bilinguals of the study. (CLK)