Abstract: As the basic unit of language, words not only conceptualize the objective world, but also convey affective information. Words containing both conceptual meanings and affective information are usually termed emotional words. Although a number of studies have been conducted to reveal the processing mechanism of emotional words, little is known about the modulation mechanism of emotional words on other stimuli, such as neutral stimuli.
Using an evaluative conditioning paradigm, three experiments were conducted to explore the modulation mechanism of emotional words on neutral stimuli’s preference. In the evaluative conditioning paradigm, a neutral stimulus (unknown Korean words, Conditional Stimuli) was paired with an emotional word (Unconditional Stimuli) and presented repeatedly during the studying phase. In the evaluative phase, after the studying phase, a preference score for the neutral stimulus was obtained to find out whether the evaluation changed towards the direction of paired affective meaning. At the end of the experiment, contingence awareness tests were performed to check the awareness level of participants to relationships between neutral stimuli and emotional words.
In experiment 1, a cover story was used to conceal the real experimental aim from the participants. The participants were asked to perform either one of two tasks on emotional words during each of two studying phases: word-class judgment versus affective judgment. Experiment 2 replicated experiment 1 except that we disturbed the fixed pairing of the relationship between neutral stimuli and emotional words to expel the potential confusion from the influence of the emotional words’ conceptual meanings on the modulation effects. In experiment 3, we changed the task from word-class judgment to word-form judgment which is distinguished from affective judgment in the word processing depth.
The results of experiment 1 indicated that regardless of which task the participants performed, their evaluation of new words was always modulated by emotional words without awareness of the contingency relationship between neutral stimuli and affective words. Experiment 2 replicated the findings even after disturbing the fixed-pairing relationship of neutral stimuli and emotional words. To clarify that the results from the two tasks reflected an independent effect of the modulation mechanism rather than an effect of the same depth required by both tasks, experiment 3 adopted new tasks of word incline-vertical judgment and affective judgment. The results of experiment 3 replicated the modulation effects of emotional words on the preferences for the neutral stimuli.
These results suggest that the modulation mechanism of emotional words on other stimuli is different from the processing of emotional words itself. The modulation process is not only independent of the awareness of the contingent relationship between CS and US, but is also not subjective to task demands. In other words, the modulation mechanism of emotional words on neutral stimuli might be based on automatic association learning, which reflects a bottom-up and automatic process. More importantly, the present study provides important evidence for the interactive view of emotion and cognition, which suggests that human behaviors are influenced by both emotional and cognitive factors.

Key words: emotional words, preferences, evaluative conditioning, contingency awareness, task demands