Intelligibility of Natively and Nonnatively Produced English Speech Presented in Noise to a Large Cohort of United States Service Members.

Purpose: A corpus of English matrix sentences produced by 60 native and nonnative speakers of English was developed as part of a multinational coalition task group. This corpus was tested on a large cohort of U.S.

Age Impacts Speech-in-Noise Recognition Differently for Nonnative and Native Listeners.

Purpose: The purpose of this study was to explore potential differences in suprathreshold auditory function among native and nonnative speakers of English as a function of age.

Method: Retrospective analyses were performed on three large data sets containing suprathreshold auditory tests completed by 5,572 participants who were self-identified native and nonnative speakers of English between the ages of 18-65 years, including a binaural tone detection test, a digit identification test, and a sentence recognition test.

Results: The analyses show a significant interaction between increasing age and participant group on tests involving speech-based stimuli (digit strings, sentences) but not on the binaural tone detection test.

Short-term retention of learning after rapid adaptation to native and non-native speecha).

Non-native, accented speech spoken by unfamiliar talkers can be challenging to recognize, but rapid improvements in perception are often observed after a short period of exposure. However, it is not clear whether these improvements are retained over multiple sessions. Stimulus variability facilitates learning for non-native speech, so it is possible it may also induce increased retention of learning for speech produced with an unfamiliar accent.

Assessment methods for determining small changes in hearing performance over time.

Although the behavioral pure-tone threshold audiogram is considered the gold standard for quantifying hearing loss, assessment of speech understanding, especially in noise, is more relevant to quality of life but is only partly related to the audiogram. Metrics of speech understanding in noise are therefore an attractive target for assessing hearing over time. However, speech-in-noise assessments have more potential sources of variability than pure-tone threshold measures, making it a challenge to obtain results reliable enough to detect small changes in performance.

Examining the context benefit in older adults: A combined behavioral-electrophysiologic word identification study.

When listening to degraded speech, listeners can use high-level semantic information to support recognition. The literature contains conflicting findings regarding older listeners' ability to benefit from semantic cues in recognizing speech, relative to younger listeners. Electrophysiologic (EEG) measures of lexical access (N400) often show that semantic context does not facilitate lexical access in older listeners; in contrast, auditory behavioral studies indicate that semantic context improves speech recognition in older listeners as much as or more than in younger listeners.

Semantic context and stimulus variability independently affect rapid adaptation to non-native English speech in young adults.

When speech is degraded or challenging to recognize, young adult listeners with normal hearing are able to quickly adapt, improving their recognition of the speech over a short period of time. This rapid adaptation is robust, but the factors influencing rate, magnitude, and generalization of improvement have not been fully described. Two factors of interest are lexico-semantic information and talker and accent variability; lexico-semantic information promotes perceptual learning for acoustically ambiguous speech, while talker and accent variability are beneficial for generalization of learning.

Younger and older adults show non-linear, stimulus-dependent performance during early stages of auditory training for non-native English.

Older adults often report difficulty understanding speech produced by non-native talkers. These listeners can achieve rapid adaptation to non-native speech, but few studies have assessed auditory training protocols to improve non-native speech recognition in older adults. In this study, a word-level training paradigm was employed, targeting improved recognition of Spanish-accented English.

Stability of Early Auditory Evoked Potential Components Over Extended Test-Retest Intervals in Young Adults.

Objectives: Synaptic damage from noise exposures can occur even in the absence of changes in hearing sensitivity in animal models. There is an unmet clinical need for measurements sensitive to such damage to the human auditory system that can augment the pure-tone audiogram. Early components (i.

Improving older adults' understanding of challenging speech: Auditory training, rapid adaptation and perceptual learning.

The literature surrounding auditory perceptual learning and auditory training for challenging speech signals in older adult listeners is highly varied, in terms of both study methodology and reported outcomes. In this review, we discuss some of the pertinent features of listener, stimulus, and training protocol. Literature regarding the elicitation of auditory perceptual learning for time-compressed speech, non-native speech, and noise-vocoded speech is reviewed, as are auditory training protocols designed to improve speech-in-noise recognition.

Effects of Listener Age and Native Language Experience on Recognition of Accented and Unaccented English Words.

Purpose Older native speakers of English have difficulty in understanding Spanish-accented English compared to younger native English speakers. However, it is unclear if this age effect would be observed among native speakers of Spanish. The current study investigates the effects of age and native language experience with Spanish on the ability to recognize words spoken in English by Spanish-accented and unaccented talkers.

Effects of listener age and native language on perception of accented and unaccented sentences.

Degradations to auditory input have deleterious effects on speech recognition performance, especially by older listeners. Alterations to timing information in speech, such as occurs in rapid or foreign-accented speech, can be particularly difficult for older people to resolve. It is currently unclear how prior language experience modulates performance with temporally altered sentence-length speech utterances.

All-night functional magnetic resonance imaging sleep studies.

Background: Previous functional magnetic resonance imaging (fMRI) sleep studies have been hampered by the difficulty of obtaining extended amounts of sleep in the sleep-adverse environment of the scanner and often have resorted to manipulations such as sleep depriving subjects before scanning. These manipulations limit the generalizability of the results.

New Method: The current study is a methodological validation of procedures aimed at obtaining all-night fMRI data in sleeping subjects with minimal exposure to experimentally induced sleep deprivation.

Adaptation to novel foreign-accented speech and retention of benefit following training: Influence of aging and hearing loss.

Adaptation to speech with a foreign accent is possible through prior exposure to talkers with that same accent. For young listeners with normal hearing, short term, accent-independent adaptation to a novel foreign accent is also facilitated through exposure training with multiple foreign accents. In the present study, accent-independent adaptation is examined in younger and older listeners with normal hearing and older listeners with hearing loss.