Poster A104, Saturday, March 25, 5:00 – 7:00 pm, Pacific Concourse
Cognitive interference modulates speech acoustics in a vowel-modified Stroop task
Caroline Niziolek1, Ian Quillen1, Kimberly Lin1, Sara Beach2, Swathi Kiran1; 1Boston University, 2Harvard Medical School
How do cognitive processes influence speaking? The Stroop effect is a classic demonstration of the interference between two cognitive processes: reading and color naming. In the current study, we used a novel variant of the Stroop test to measure whether this interference influences the acoustic properties of speech. Seventeen healthy control participants named the color of words in three categories: 1) congruent words (e.g. “red” written in red), 2) color-incongruent words (e.g. “green” written in red), and 3) vowel-incongruent words with phonetic properties that partially matched their text color (e.g. “rid” written in red). We hypothesized that the cognitive effort needed to inhibit reading in this third condition—saying “red”, not “rid”—could affect the acoustics of the speech that was produced. For example, the correct spoken response (“red”) could more acoustically resemble the inhibited word “rid”; alternatively, the acoustics could be influenced in the opposite direction, resembling “rad”, which would serve to accentuate the acoustic contrast between the spoken and inhibited words. A classic Stroop effect was evident when comparing reaction times between congruent words and color-incongruent words. Interestingly, we found no significant difference in reaction times between congruent and vowel-incongruent trials, but preliminary acoustic analyses of the first formant frequency (F1) showed that some subjects systematically modulated their productions in the presence of incongruent vowels. These changes in acoustic properties can lend insight into how the brain integrates multiple pieces of information to produce speech.
Topic Area: PERCEPTION & ACTION: Motor control