Training humans in non-native phoneme perception using a monkey psychoacoustic procedure.

Humans were trained to categorize problem non-native phonemes using an animal psychoacoustic procedure that trains monkeys to greater than 90% correct in phoneme identification [Sinnott and Gilmore, Percept. Psychophys. 66, 1341-1350 (2004)].

Using monkeys to explore perceptual "loss" versus "learning" models in English and Spanish voice-onset-time perception.

Cross-language research using synthetic voice-onset-time series over the past 40 years suggests that the Spanish lead contrast is acoustically less salient than the English lag contrast. This study examined monkey identification of a labial consonant-vowel voice-onset-time (CV VOT) series (-60 to +70 ms) in order to obtain a linguistically unbiased estimate of lead versus lag salience. Comparisons were made with both English and Spanish adult human listeners.

Perception of place-of-articulation information in natural speech by monkeys versus humans.

Four monkeys and 6 humans representing five different native languages were compared in the ability to categorize natural CV tokens of /b/ versus /d/ produced by 4 talkers of American English (2 male, 2 female) in four vowel contexts (/i, e, a, u/). A two-choice "left/right" procedure was used in which both percentage correct and response time data were compared between species. Both measures indicated striking context effects for monkeys, in that they performed better for the back vowels /a/ and /u/ than for the front vowels /i/ and /e/.

Effects of aging on speech sound discrimination in the Mongolian gerbil.

The of this study was to examine the hypothesis that aging would adversely effect speech sound discrimination in the Mongolian gerbil, as assessed by behavioral techniques. The involved measuring difference limens (DLs) for frequency changes along three synthetic speech continua (vowel, liquid, stop-consonant) in 25 gerbils as a function of age up to 36 mo. Absolute thresholds were also measured in the aging gerbils to verify normal hearing.

A Comparison of Pure Tone Auditory Thresholds in Human Infants and Adults.

Pure tone auditory thresholds for frequencies from .250 to 8.0 kHz were obtained from 277-to-11-month-old human infants and nine adults using a go-no-go operant head-turning technique combined with an adaptive staircase (tracking) discrimination procedure.