Effects of noise on adults' word learning

Abstract

Neighborhood density, the number of similar sounding words, and phonotactic probability, the likelihood of occurrence of a sound sequence, influence word learning by adults in quiet listening conditions. Specifically, Storkel, Armbruster, and Hogan (2006) found that adults learned high density words and low probability words more accurately. This study examined how neighborhood density and phonotactic probability influence adults’ word learning in noisy conditions. Fifty-two college students learned nonwords varying in neighborhood density and phonotactic probability at either +8 dB SNR or 0 dB SNR, and learning was measured in a picture naming task. Results showed a significant interaction of density, probability, and noise level. At +8 dB SNR, no effects were significant. At 0 dB SNR, density interacted with probability, showing better learning when density and probability converged. In other words, for low probability words, learning was better when density was also low (i.e., low-low optimal), whereas for high probability words, learning was better when density was also high (i.e., high-high optimal). These results indicate that noise dampens the effects of probability and density in a moderately noisy condition (i.e., +8 dB SNR) and requires a convergence of probability and density in the noisiest condition (i.e., 0 dB SNR).