No description available.

Three aspects of stimulus content, i.e. meaningfulness, familiarity and task relevance, were manipulated without the subjects awareness. A number of subliminal (backward-masked) stimuli were presented to the subject whose task it was to estimate an interval of 1 sec (starting with the presentation-flash) by pressing a button. Supraliminal words were randomly interspersed among these, subliminal stimuli, appearing above or below the masked field. Whenever the subject detected a previously assigned target among the supraliminal stimuli, he/she was required to press the button as fast as possible. The meaningfulness of the subliminal material was manipulated using words, nonwords and blanks. Three groups of words were used: the targets, the nontargets and other, 'new' words (which were never presented supraliminally). Task relevance (targets vs. nontargets) and familiarity ('new' words vs. other words) were thus manipulated. Unexpectedly, detection performance was better with words than with nonwords. This suggests that detection is a late process drawing on lexical information. Several components of the event related potential (ERP) differentiated as early as 140 msec poststimulus between sub-and supraliminal conditions. More importantly, differences within the subliminal conditions were observed: familiarity was discriminated after 260 msec and simple presence of a string after 300 msec. These results are consistent with the conclusions drawn from detection performance, and they support the notion that backward masking does not disrupt processing. / Arts, Faculty of / Psychology, Department of / Graduate

No description available.

Background: In developing the PB-50 word lists, J. P. Egan suggested five developmental principles, two of which were "equal average difficulty" and an "equal range of difficulty" among the lists (page 963). Egan was satisfied that each of the 20 PB-50 lists had equivalent ranges of recognition performances and that the lists produced the same average performances. This was accomplished in preliminary studies that measured the recognition performance of each word and eliminated words that were always or never correct. In preparing for studies of interrupted words, we needed to know the range of difficulty inherent in the speaker specific NU-6 and Maryland CNC materials we planned to use when those words were not interrupted. There were only a few studies in the literature that touched on the range of difficulty characteristic of the word-recognition materials in common usage. The paucity of this information prompted this investigation whose scope broadened to include the CID W-22, Maryland CNC, NU-6, and PB-50 materials spoken by a variety of speakers. Purpose: The purpose was to evaluate the homogeneity with respect to intelligibility of the words that comprise several of the common word-recognition materials used in audiologic evaluations. Research Design: Both retrospective (10) and prospective (3) studies were involved. Data from six of the retrospective studies were from our labs. The prospective studies involved both listeners with normal hearing for pure tones and listeners with sensorineural hearing loss. Study Sample: The sample sizes for the 13 data sets ranged from 24 to 1,030, with 24 the typical number for listeners with normal hearing. Data Collection and Analysis: The retrospective data were from published studies and archived data from our laboratories. The prospective studies involved presentation of the word-recognition materials to the listeners at a comfortable level. An item analysis was conducted on each data set with descriptive statistics used to characterize the data. Additionally, skewness coefficients were calculated on the distributions of word performances and the interquartile range was used to determine minor and major outliers within each set of 200 words and their component 50-word lists (300 words for the Maryland CNCs). Results: For listeners with normal hearing the majority of performances on the words within a 50-word list were better than the mean performance, which produced negatively skewed distributions with outlier performances in every list. For listeners with sensorineural hearing loss the performances on the words within a 50-word list were evenly distributed above and below the mean performance, which yielded essentially normal distributions with few outliers. There were a few words on which performances were better by the listeners with hearing loss. Conclusions: Every list of word-recognition materials has a few words on which recognition performances are noticeably poorer than performances on the majority of the remaining words. If the intention of an experiment is to evaluate performance at the word level, then identifying these "outliers" becomes a necessity. Although not evaluated in this report, the implications for 25-word lists are they should be based on recognition-performance data and not compiled arbitrarily.

Background: The Words-in-Noise Test (WIN) was developed as an instrument to quantify the ability of listeners to understand monosyllabic words in background noise using multitalker babble (Wilson, 2003). The 50% point, which is calculated with the Spearman-Kärber equation (Finney, 1952), is used as the evaluative metric with the WIN materials. Initially, the WIN was designed as a 70-word instrument that presented ten unique words at each of seven signal-to-noise ratios from 24 to 0 dB in 4 dB decrements. Subsequently, the 70-word list was parsed into two 35-word lists that achieved equivalent recognition performances (Wilson and Burks, 2005). This report involves the development of a third list (WIN List 3) that was developed to serve as a practice list to familiarize the participant with listening to words presented in background babble. Purpose: To determine - on young listeners with normal hearing and on older listeners with sensorineural hearing loss - the psychometric properties of the WIN List 3 materials. Research Design: A quasi-experimental, repeated-measures design was used. Study Sample: Twenty-four young adult listeners (M=21.6 yr)with normal pure-tone thresholds (≤20 dB HL at 250 to 8000 Hz) and 24 older listeners (M=65.9 yr) with sensorineural hearing loss participated. Data Collection and Analysis: The level of the babble was fixed at 80 dB SPL with the level of the words varied from 104 to 80 dB SPL in 4 dB decrements. Results: For listeners with normal hearing, the 50% points for Lists 1 and 2 were similar (4.3 and 5.1 dB S/N, respectively), both of which were lower than the 50% point for List 3 (7.4 dB S/N). A similar relation was observed with the listeners with hearing loss, 50% points for Lists 1 and 2 of 12.2 and 12.4 dB S/N, respectively, compared to 15.8 dB S/N for List 3. The differences between Lists 1 and 2 and List 3 were significant. The relations among the psychometric functions and the relations among the individual data both reflected these differences. Conclusions: The significantz3 dB difference between performances on WIN Lists 1 and 2 and on WIN List 3 by the listeners with normal hearing and the listeners with hearing loss dictates caution with the use of List 3. The use of WIN List 3 should be reserved for ancillary purposes in which equivalent recognition performances are not required, for example, as a practice list or a stand alone measure.

Background: The Speech Recognition in Noise Test (SPRINT) is a word-recognition instrument that presents the 200 Northwestern University Auditory Test No. 6 (NU-6) words binaurally at 50 dB HL in a multitalker babble at a 9 dB signal-to-noise ratio (S/N) (Cord et al, 1992). The SPRINT was developed by and used by the Army as a more valid predictor of communication abilities (than pure-tone thresholds or word-recognition in quiet) for issues involving fitness for duty from a hearing perspective of Army personnel. The Words-in-Noise test (WIN) is a slightly different word-recognition task in a fixed level multitalker babble with 10 NU-6 words presented at each of 7 S/N from 24 to 0 dB S/N in 4 dB decrements (Wilson, 2003; Wilson and McArdle, 2007). For the two instruments, both the babble and the speakers of the words are different. The SPRINT uses all 200 NU-6 words, whereas the WIN uses a maximum of 70 words. Purpose: The purpose was to compare recognition performances by 24 young listeners with normal hearing and 48 older listeners with sensorineural hearing on the SPRINT and WIN protocols. Research Design: A quasi-experimental, mixed model design was used. Study Sample: The 24 young listeners with normal hearing (19 to 29 years, mean = 23.3 years) were from the local university and had normal hearing (≤20 dB HL; American National Standards Institute, 2004) at the 250-8000 Hz octave intervals. The 48 older listeners with sensorineural hearing loss (60 to 82 years, mean = 69.9 years) had the following inclusion criteria: (1) a threshold at 500 Hz between 15 and 30 dB HL, (2) a threshold at 1000 Hz between 20 and 40 dB HL, (3) a three-frequency pure-tone average (500, 1000, and 2000 Hz) of ≤40 dB HL, (4) word-recognition scores in quiet ≥40%, and (5) no history of middle ear or retrocochlear pathology as determined by an audiologic evaluation. Data Collection and Analysis: The speech materials were presented bilaterally in the following order: (1) the SPRINT at 50 dB HL, (2) two half lists of NU-6 words in quiet at 60 dB HL and 80 dB HL, and (3) the two 35-word lists of the WIN materials with the multitalker babble fixed at 60 dB HL. Data collection occurred during a 40-60 minute session. Recognition performances on each stimulus word were analyzed. Results: The listeners with normal hearing obtained 92.5% correct on the SPRINT with a 50% point on the WIN of 2.7 dB S/N. The listeners with hearing loss obtained 65.3% correct on the SPRINT and a WIN 50% point at 12.0 dB S/N. The SPRINT and WIN were significantly correlated (r = -0.81, p < .01), indicating that the SPRINT had good concurrent validity. The high-frequency, pure-tone average (1000, 2000, 4000 Hz) had higher correlations with the SPRINT, WIN, and NU-6 in quiet than did the traditional three-frequency pure-tone average (500, 1000, 2000 Hz). Conclusions: Graphically and numerically the SPRINT and WIN were highly related, which is indicative of good concurrent validity of the SPRINT.

Purpose: To analyze the 50% correct recognition data that were from the Wilson et al (this issue) study and that were obtained from 24 listeners with normal hearing; also to examine whether acoustic, phonetic, or lexical variables can predict recognition performance for monosyllabic words presented in speech-spectrum noise. Research Design: The specific variables are as follows: (a) acoustic variables (i.e., effective root-mean-square sound pressure level, duration), (b) phonetic variables (i.e., consonant features such as manner, place, and voicing for initial and final phonemes; vowel phonemes), and (c) lexical variables (i.e., word frequency, word familiarity, neighborhood density, neighborhood frequency). Data Collection and Analysis: The descriptive, correlational study will examine the influence of acoustic, phonetic, and lexical variables on speech recognition in noise performance. Results: Regression analysis demonstrated that 45% of the variance in the 50% point was accounted for by acoustic and phonetic variables whereas only 3% of the variance was accounted for by lexical variables. These findings suggest that monosyllabic word-recognition-in-noise is more dependent on bottom-up processing than on top-down processing. Conclusions: The results suggest that when speech-in-noise testing is used in a pre- and post-hearing-aid-fitting format, the use of monosyllabic words may be sensitive to changes in audibility resulting from amplification.

Background: So that portions of the classic Miller, Heise, and Lichten (1951) study could be replicated, new recorded versions of the words and digits were made because none of the three common monosyllabic word lists (PAL PB-50, CID W-22, and NU-6) contained the 9 monosyllabic digits (1-10, excluding 7) that were used by Miller et al. It is well established that different psychometric characteristics have been observed for different lists and even for the same materials spoken by different speakers. The decision was made to record four lists of each of the three monosyllabic word sets, the monosyllabic digits not included in the three sets of word lists, and the CID W-1 spondaic words. A professional female speaker with a General American dialect recorded the materials during four recording sessions within a 2-week interval. The recording order of the 582 words was random. Purpose: To determine - on listeners with normal hearing - the psychometric properties of the five speech materials presented in speech-spectrum noise. Research Design: A quasi-experimental, repeated-measures design was used. Study Sample: Twenty-four young adult listeners (M = 23 years) with normal pure-tone thresholds (≤20-dB HL at 250 to 8000 Hz) participated. The participants were university students who were unfamiliar with the test materials. Data Collection and Analysis: The 582 words were presented at four signal-to-noise ratios (SNRs; -7-, -2-, 3-, and 8-dB) in speech-spectrum noise fixed at 72-dB SPL. Although the main metric of interest was the 50% point on the function for each word established with the Spearman-Kärber equation (Finney, 1952), the percentage correct on each word at each SNR was evaluated. The psychometric characteristics of the PB-50, CID W-22, and NU-6 monosyllabic word lists were compared with one another, with the CID W-1 spondaic words, and with the 9 monosyllabic digits. Results: Recognition performance on the four lists within each of the three monosyllabic word materials were equivalent, ±0.4 dB. Likewise, word-recognition performance on the PB-50, W-22, and NU-6 word lists were equivalent, ±0.2 dB. The mean recognition performance at the 50% point with the 36 W-1 spondaic words was ∼6.2 dB lower than the 50% point with the monosyllabic words. Recognition performance on the monosyllabic digits was 1-2 dB better than mean performance on the monosyllabic words. Conclusions: Word-recognition performances on the three sets of materials (PB-50, CID W-22, and NU-6) were equivalent, as were the performances on the four lists that make up each of the three materials. Phonetic/phonemic balance does not appear to be an important consideration in the compilation of word-recognition lists used to evaluate the ability of listeners to understand speech. A companion paper examines the acoustic, phonetic/phonological, and lexical variables that may predict the relative ease or difficulty for which these monosyllable words were recognized in noise (McArdle and Wilson, this issue).

Purpose: The purpose of this study was to examine in listeners with normal hearing and listeners with sensorineural hearing loss the within- and between-group differences obtained with 4 commonly available speech-in-noise protocols. Method: Recognition performances by 24 listeners with normal hearing and 72 listeners with sensorineural hearing loss were compared for 4 speech-in-noise protocols that varied with respect to the amount of contextual cues conveyed in the target signal. The protocols studied included the Bamford-Kowal-Bench Speech-in-Noise Test (BKB-SIN; Etymōtic Research, 2005; J. Bench, A. Kowal, & J. Bamford, 1979; P. Niquette et al., 2003), the Quick Speech-in-Noise Test (QuickSIN; M. C. Killion, P. A. Niquette, G. I. Gudmundsen, L. J. Revit, & S. Banerjee, 2004), and the Words-in-Noise test (WIN; R. H. Wilson, 2003; R. H. Wilson & C. A. Burks, 2005), each of which used multitalker babble and a modified method of constants, as well as the Hearing in Noise Test (HINT; M. Nilsson, S. Soli, & J. Sullivan, 1994), which used speech-spectrum noise and an adaptive psychophysical procedure. Results: The 50% points for the listeners with normal hearing were in the 1- to 4-dB signal-to-babble ratio (S/B) range and for the listeners with hearing loss in the 5- to 14-dB S/B range. Separation between groups was least with the BKB-SIN and HINT (4-6 dB) and most with the QuickSIN and WIN (8-10 dB). Conclusion: The QuickSIN and WIN materials are more sensitive measures of recognition performance in background noise than are the BKB-SIN and HINT materials.

The purpose of this study was to examine the feasibility of using digit triplets in multitalker babble as a paradigm to measure the ability of patients to understand speech in background noise. Nine digits (one to ten, excluding seven) were randomized into triplet sets and embedded in multitalker babble at 6- to -20-dB signal-to-babble (S/B) ratios. Recognition performances by 24 listeners with normal hearing and 48 listeners with sensorineural hearing loss were measured for the digit triplets and for monosyllabic words both in multitalker babble presented at 80-dB SPL. There was essentially no overlap between the distributions of performances by the two groups of listeners on either of the materials. For both groups of listeners, the difference between performances on the materials at the 50% point was approximately 18 dB. Both the word and digit materials in a background of multitalker babble are sensitive to the inabilities of listeners with hearing loss to understand speech in background noise.