What Does Language Have to Do With It? The Impact of Age and Bilingual Experience on Inhibitory Control in an Auditory Dichotic Listening Task.

Purpose The purpose of the current study was to examine inhibition of irrelevant information in younger and older English monolingual and Spanish-English bilingual adults. Method Sixty-one participants divided into four groups: 15 younger English monolinguals, 16 younger Spanish-English bilinguals, 15 older English monolinguals, and 15 older Spanish-English bilinguals participated in this study. Younger participants were 18-25 years of age, and older participants were 47-62 years of age. Bilingual participants had learned Spanish from birth and began learning English by the age of 3 years old (SD = 3.1). All participants had hearing thresholds of < 25 dB HL from 250 to 4000 Hz, bilaterally (American National Standards Institute [ANSI], 2004) and were right-handed. Inhibition was measured using a forced-attention dichotic consonant vowel listening task with a prime stimulus and the Simon task, a nonverbal visual test. Results Younger participants were better able to inhibit the irrelevant auditory and visual stimuli and modulate their attention according to the instructions that they were given compared to the older participants. However, no significant differences in inhibition performance or attention modulation were evidenced between the monolingual and bilingual groups in any of the dichotic listening conditions or on the Simon task. Conclusions No significant differences in performance on an auditory or a visual test of inhibition of irrelevant information was evidenced between the monolingual and bilingual participants in this study. These findings suggest that younger and older adult, early balanced Spanish-English bilinguals may not exhibit an advantage in the inhibition of irrelevant information compared to younger and older adult English monolinguals.