Article

Neural Correlates of Selective Attention With Hearing Aid Use Followed by ReadMyQuips Auditory Training Program

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Abstract

Objectives: The objectives of this study were to investigate the effects of hearing aid use and the effectiveness of ReadMyQuips (RMQ), an auditory training program, on speech perception performance and auditory selective attention using electrophysiological measures. RMQ is an audiovisual training program designed to improve speech perception in everyday noisy listening environments. Design: Participants were adults with mild to moderate hearing loss who were first-time hearing aid users. After 4 weeks of hearing aid use, the experimental group completed RMQ training in 4 weeks, and the control group received listening practice on audiobooks during the same period. Cortical late event-related potentials (ERPs) and the Hearing in Noise Test (HINT) were administered at prefitting, pretraining, and post-training to assess effects of hearing aid use and RMQ training. An oddball paradigm allowed tracking of changes in P3a and P3b ERPs to distrac-tors and targets, respectively. Behavioral measures were also obtained while ERPs were recorded from participants. Results: After 4 weeks of hearing aid use but before auditory training , HINT results did not show a statistically significant change, but there was a significant P3a reduction. This reduction in P3a was correlated with improvement in d prime (d′) in the selective attention task. Increased P3b amplitudes were also correlated with improvement in d′ in the selective attention task. After training, this correlation between P3b and d′ remained in the experimental group, but not in the control group. Similarly, HINT testing showed improved speech perception post training only in the experimental group. The criterion calculated in the auditory selective attention task showed a reduction only in the experimental group after training. ERP measures in the auditory selective attention task did not show any changes related to training. Conclusions: Hearing aid use was associated with a decrement in involuntary attention switch to distractors in the auditory selective attention task. RMQ training led to gains in speech perception in noise and improved listener confidence in the auditory selective attention task.

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... Computation of the P3 amplitude used an integration window of 40 ms centered at peak. Similar time windows for P3 quantification were used in our previous P3 studies (Nie et al, 2014;Rao et al., 2017). ...
... Auditory training programs are designed to exploit brain plasticity in order to improve speech perception in complex listening situations. Brain imaging tools can be useful in tracking these neurophysiological changes induced by perceptual learning, including measures of neural activation, oscillations, and functional connectivity patterns in the neural substrate dedicated to speech processing (Miller, Zhang, & Nelson, 2016;Rao et al., 2017;Song, Skoe, Banai, & Kraus, 2012;Yu et al., 2017;Zhang & Wang, 2010). Additionally, electrophysiological measures may provide useful information for the development of effective auditory training strategies, as they could track improvements in sensory or cognitive processes underlying speech perception in background noise. ...
... The CV syllables were presented via bilateral Etymotic ER-2 insert headphones using EEvoke software (ANT Inc., Netherlands). The speech signals were presented at 60 dB SL relative to the individual listeners' hearing threshold at 1 kHz (Koerner et al., 2016;Koerner and Zhang, 2015;Nie et al., 2014;Rao et al., 2017). Participants were presented with two listening conditions in both the EEG and behavioral tests: signals in quiet and signals in a four-talker speech babble noise. ...
... Computation of the P3 amplitude used an integration window of 40 ms centered at peak. Similar time windows for P3 quantification were used in our previous P3 studies (Nie et al., 2014;Rao et al., 2017). ...
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This study examined how speech babble noise differentially affected the auditory P3 responses and the associated neural oscillatory activities for consonant and vowel discrimination in relation to segmental- and sentence-level speech perception in noise. The data were collected from 16 normal-hearing participants in a double-oddball paradigm that contained a consonant (/ba/ to /da/) and vowel (/ba/ to /bu/) change in quiet and noise (speech-babble background at a -3 dB signal-to-noise ratio) conditions. Time-frequency analysis was applied to obtain inter-trial phase coherence (ITPC) and event-related spectral perturbation (ERSP) measures in delta, theta, and alpha frequency bands for the P3 response. Behavioral measures included percent correct phoneme detection and reaction time as well as percent correct IEEE sentence recognition in quiet and in noise. Linear mixed-effects models were applied to determine possible brain-behavior correlates. A significant noise-induced reduction in P3 amplitude was found, accompanied by significantly longer P3 latency and decreases in ITPC across all frequency bands of interest. There was a differential effect of noise on consonant discrimination and vowel discrimination in both ERP and behavioral measures, such that noise impacted the detection of the consonant change more than the vowel change. The P3 amplitude and some of the ITPC and ERSP measures were significant predictors of speech perception at segmental- and sentence-levels across listening conditions and stimuli. These data demonstrate that the P3 response with its associated cortical oscillations represents a potential neurophysiological marker for speech perception in noise.
... In sentence recognition, however, the current research with regards to the effect of auditory training on subsequent sentence identification in noise is inconclusive. For instance, Levitt et al. (2011) and Rao et al. (2017), both using ReadMyQuips auditory training program, and Sweetow and Sabes (2006) and Olson et al. (2013), using Listening and Communication Enhancement auditory training program, demonstrated the efficiency of auditory training on auditory sentence identification in noise, in hearing-aid users. However, Bock and Abrams (2013) and Abrams et al. (2015) reported no effects of auditory training on sentence identification in noise in hearing aid users. ...
... Most likely, this was due to using only one session of training in the present study. One may speculate that by providing several sessions of auditory training when background noise is added to training materials, then auditory training becomes an active training method (i.e., more challenging due to more degradation of the speech signal, see Rao et al., 2017) that subsequently would result in better HINT performance. In their review, however, Henshaw and Ferguson (2013) evaluated the effects of auditory training on aural rehabilitation of people with hearing loss. ...
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This study aimed to examine the efficacy and maintenance of short-term (one-session) gated audiovisual speech training for improving auditory sentence identification in noise in experienced elderly hearing-aid users. Twenty-five hearing aid users (16 men and 9 women), with an average age of 70.8 years, were randomly divided into an experimental (audiovisual training, n = 14) and a control (auditory training, n = 11) group. Participants underwent gated speech identification tasks comprising Swedish consonants and words presented at 65 dB sound pressure level with a 0 dB signal-to-noise ratio (steady-state broadband noise), in audiovisual or auditory-only training conditions. The Hearing-in-Noise Test was employed to measure participants' auditory sentence identification in noise before the training (pre-test), promptly after training (post-test), and 1 month after training (one-month follow-up). The results showed that audiovisual training improved auditory sentence identification in noise promptly after the training (post-test vs. pre-test scores); furthermore, this improvement was maintained 1 month after the training (one-month follow-up vs. pre-test scores). Such improvement was not observed in the control group, neither promptly after the training nor at the one-month follow-up. However, no significant between-groups difference nor an interaction between groups and session was observed. Conclusion: Audiovisual training may be considered in aural rehabilitation of hearing aid users to improve listening capabilities in noisy conditions. However, the lack of a significant between-groups effect (audiovisual vs. auditory) or an interaction between group and session calls for further research.
... Despite gains achieved through advanced signal processing technology of hearing aids (HAs), users report persistent problems in speech perception in the presence of noise relative to premorbid experience (Kochkin, 2007), and rehabilitative training has been proposed to address these problems (Boothroyd, 2007; Moore and Amitay, 2007). A topic of current interest in audiology and aging neuroscience is the benefits and neuromodulatory effects from HA use and auditory training (Fuller and Levitt, 2012; Ferguson and Henshaw, 2015; Morais et al., 2015; Rao et al., 2017). Electroencephalography (EEG) studies have shown mixed results at the subcortical (Philibert et al., 2005; Dawes et al., 2013) and cortical levels (Bertoli et al., 2011; Dawes et al., 2014). ...
... RMQ is a computerized program designed to improve speech understanding through AV training in the presence of background noise. RMQ training has been shown to improve HA users' speech-in-noise perception as well as confidence in target detection in auditory selective attention task (Abrams et al., 2015; Rao et al., 2017). ...
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Evidence for a clinically significant effect of acclimatization to hearing aids is mixed. The aim of this study was to test for auditory acclimatization effects in new unilateral and bilateral adult hearing aid users. Hypotheses were i) there would be improvements in aided speech recognition in new hearing aid users, compared with unaided listening and with a control group of experienced hearing aid users, and ii) improvements would correlate with severity of hearing loss, hearing aid use, and cognitive capacity. Speech recognition in noise was measured for a 65 and a 75 dB SPL target with the Four Alternative Auditory Feature test. Speech recognition in noise was measured within 1 week of fitting and retested at 12 weeks postfitting in new hearing aid users (16 unilateral and 16 bilateral fit). A control group of experienced hearing aid users (n = 17) was tested over a similar time scale. Cognitive capacity (reaction time and working memory) was measured, and self-reported change in performance was assessed using the Speech, Spatial and Qualities of Hearing Scale. Hearing aid use was assessed via data logging at the completion of the study. Mean improvements in speech recognition of up to 4% were observed across conditions and across groups consistent with a general practice effect. On average there was no evidence of auditory acclimatization in the new hearing aid user groups in terms of improvement in aided listening conditions above that observed in unaided recognition or in the control group. There was no correlation between change in aided speech recognition and severity of hearing loss, hearing aid use, or cognitive capacity. New users reported significant improvement over time in aided performance on a self-report questionnaire compared with the control group. On average, there was no improvement over time in new users' aided speech recognition relative to unaided recognition or to the control group. This does not support a robust acclimatization effect with nonlinear hearing aids. Test-retest variability may obscure small average acclimatization effects; variability was not accounted for by individual differences in severity of hearing loss, hearing aid use, or cognitive capacity. New users' subjective report of increased benefit over time may be reflective of other aspects of adjustment to hearing aid use not examined in this study.
Article
Background: Numerous studies have demonstrated that improving the ability to understand speech in noise can be a difficult task for adults with hearing aids (HAs). If HA users want to improve their speech understanding ability, specific training may be needed. Auditory training (AT) is one type of intervention that may enhance speech recognition abilities for adult HA users. Purpose: The purpose of this study was to examine the behavioral effects of an AT program called Listening and Communication Enhancement (LACE) in the DVD format in new and experienced HA users. While some research has been conducted using the computer version of this program, no research to date has been conducted on the efficacy of the DVD version of the LACE training program in both new and experienced HA users. Research design: An experimental, prospective repeated measures group design, with random assignment. Study sample: Twenty-nine adults with hearing loss were assigned to one of three groups: new HA plus training, experienced HA plus training, or control (new HA users with no training during the study but provided with training afterward). New HA aid users were randomly assigned to either the training or control group. Intervention: Participants in the training groups completed twenty 30 min training lessons from the LACE DVD program at home over a period of 4 wk. Data collection: Participants in both training groups were evaluated at baseline, after 2 wk of training and again after 4 wk of training. Participants in the control group were evaluated at baseline and after 4 wk of HA use. Several objective listening measures were administered including speech in noise, rapid speech, and competing sentences tasks. Subjective measures included evaluating the participants' perception of the intervention as well as their perceptions of functional listening abilities. Results: Findings indicate that both new and experienced users improved their understanding of speech in noise, understanding of competing sentences, and communication function after training in comparison to a control group. Effect size calculations suggested that a larger training effect was observed for new HA users compared to experienced HA users. New HA users also reported greater benefit from training compared to experienced users. AT with the LACE DVD format should be encouraged, particularly among new HA users, to improve understanding in difficult listening conditions.
Article
Importance Sensorineural hearing loss is the third leading cause of years lived with disability worldwide. Cochlear implants may provide a viable alternative to hearing aids for this type of hearing loss. The Coverage and Analysis Group at the Centers for Medicare & Medicaid Services was interested in an evaluation of recently published literature on this topic. In addition, this meta-analysis is to our knowledge the first to evaluate quality-of-life (QOL) outcomes in adults with cochlear implants. Objective To evaluate the communication-related outcomes and health-related QOL outcomes after unilateral or bilateral cochlear implantation in adults with sensorineural hearing loss. Data Sources MEDLINE, Cochrane Central Register of Controlled Trials, Scopus, and previous reports from January 1, 2004, through May 31, 2012. Study Selection Published studies of adult patients undergoing unilateral or bilateral procedures with multichannel cochlear implants and assessments using open-set sentence tests, multisyllable word tests, or QOL measures. Data Extraction Five researchers extracted information on population characteristics, outcomes of interest, and study design and assessed the studies for risk of bias. Discrepancies were resolved by consensus. Results A total of 42 studies met the inclusion criteria. Most unilateral implant studies showed a statistically significant improvement in mean speech scores as measured by open-set sentence or multisyllable word tests; meta-analysis revealed a significant improvement in QOL after unilateral implantation. Results from studies assessing bilateral implantation showed improvement in communication-related outcomes compared with unilateral implantation and additional improvements in sound localization compared with unilateral device use or implantation only. Based on a few studies, the QOL outcomes varied across tests after bilateral implantation. Conclusions and Relevance Unilateral cochlear implants provide improved hearing and significantly improve QOL, and improvements in sound localization are noted for bilateral implantation. Future studies of longer duration, higher-quality reporting, and large databases or registries of patients with long-term follow-up data are needed to yield stronger evidence.
Article
Neural slowing is commonly noted in older adults, with consequences for sensory, motor, and cognitive domains. One of the deleterious effects of neural slowing is impairment of temporal resolution; older adults, therefore, have reduced ability to process the rapid events that characterize speech, especially in noisy environments. Although hearing aids provide increased audibility, they cannot compensate for deficits in auditory temporal processing. Auditory training may provide a strategy to address these deficits. To that end, we evaluated the effects of auditory-based cognitive training on the temporal precision of subcortical processing of speech in noise. After training, older adults exhibited faster neural timing and experienced gains in memory, speed of processing, and speech-in-noise perception, whereas a matched control group showed no changes. Training was also associated with decreased variability of brainstem response peaks, suggesting a decrease in temporal jitter in response to a speech signal. These results demonstrate that auditory-based cognitive training can partially restore age-related deficits in temporal processing in the brain; this plasticity in turn promotes better cognitive and perceptual skills.
Article
To provide a brief history of speech comprehension training systems and an overview of research on auditory and cognitive aging as background to recommendations for future directions for rehabilitation. Two distinct domains were reviewed: one concerning technological and the other concerning psychological aspects of training. Historical trends and advances in these 2 domains were interrelated to highlight converging trends and directions for future practice. Over the last century, technological advances have influenced both the design of hearing aids and training systems. Initially, training focused on children and those with severe loss for whom amplification was insufficient. Now the focus has shifted to older adults with relatively little loss but difficulties listening in noise. Evidence of brain plasticity from auditory and cognitive neuroscience provides new insights into how to facilitate perceptual (re-)learning by older adults. There is a new imperative to complement training to increase bottom-up processing of the signal with more ecologically valid training to boost top-down information processing based on knowledge of language and the world. Advances in digital technologies enable the development of increasingly sophisticated training systems incorporating complex meaningful materials such as music, audiovisual interactive displays, and conversation.
Article
Evaluated the habituation effects on the P300 or P3 event-related brain potential elicited with a simple auditory stimulus discrimination task. A total of 40 undergraduates participated. In Exp 1, neither the component amplitude nor latency changed across trials when the target probability was 10%, 30%, or 50%. In Exp 2, P3 amplitude declined significantly between the 1st and 10th trial blocks, with no decrements in target-detection performance. In Exp 3, P3 amplitude again declined between the 1st and 9th trial blocks, but it increased significantly on the 10th block when the target stimulus changed, thereby demonstrating dishabituation. Another decrease in amplitude occurred by the 15th trial block. P3 latency tended to increase with repeated presentations but decreased with the stimulus change. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
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Book
Detection Theory is an introduction to one of the most important tools for analysis of data where choices must be made and performance is not perfect. Originally developed for evaluation of electronic detection, detection theory was adopted by psychologists as a way to understand sensory decision making, then embraced by students of human memory. It has since been utilized in areas as diverse as animal behavior and X-ray diagnosis. This book covers the basic principles of detection theory, with separate initial chapters on measuring detection and evaluating decision criteria. Some other features include: complete tools for application, including flowcharts, tables, pointers, and software;. student-friendly language;. complete coverage of content area, including both one-dimensional and multidimensional models;. separate, systematic coverage of sensitivity and response bias measurement;. integrated treatment of threshold and nonparametric approaches;. an organized, tutorial level introduction to multidimensional detection theory;. popular discrimination paradigms presented as applications of multidimensional detection theory; and. a new chapter on ideal observers and an updated chapter on adaptive threshold measurement. This up-to-date summary of signal detection theory is both a self-contained reference work for users and a readable text for graduate students and other researchers learning the material either in courses or on their own. © 2005 by Lawrence Erlbaum Associates, Inc. All rights reserved.
Article
Neurocognitive studies have shown that extensive musical training enhances P3a and P3b event-related potentials for infrequent target sounds, which reflects stronger attention switching and stimulus evaluation in musicians than in nonmusicians. However, it is unknown whether the short-term plasticity of P3a and P3b responses is also enhanced in musicians. We compared the short-term plasticity of P3a and P3b responses to infrequent target sounds in musicians and nonmusicians during auditory perceptual learning tasks. Target sounds, deviating in location, pitch, and duration with three difficulty levels, were interspersed among frequently presented standard sounds in an oddball paradigm. We found that during passive exposure to sounds, musicians had habituation of the P3a, while nonmusicians showed enhancement of the P3a between blocks. Between active tasks, P3b amplitudes for duration deviants were reduced (habituated) in musicians only, and showed a more posterior scalp topography for habituation when compared to P3bs of nonmusicians. In both groups, the P3a and P3b latencies were shortened for deviating sounds. Also, musicians were better than nonmusicians at discriminating target deviants. Regardless of musical training, better discrimination was associated with higher working memory capacity. We concluded that music training enhances short-term P3a/P3b plasticity, indicating training-induced changes in attentional skills.
Article
Behavioral and electrophysiological measures of target and distractor processing were examined in an auditory selective attention task before and after three weeks of distractor suppression training. Behaviorally, training improved target recognition and led to less conservative and more rapid responding. Training also effectively shortened the temporal distance between distractors and targets needed to achieve a fixed level of target sensitivity. The effects of training on event-related potentials were restricted to the distracting stimulus: earlier N1 latency, enhanced P2 amplitude, and weakened P3 amplitude. Nevertheless, as distractor P2 amplitude increased, so too did target P3 amplitude, connecting experience-dependent changes in distractor processing with greater distinctiveness of targets in working memory. We consider the effects of attention training on the processing priorities, representational noise, and inhibitory processes operating in working memory.
Article
It has been clear for almost two decades that cortical representations in adult animals are not fixed entities, but rather, are dynamic and are continuously modified by experience. The cortex can preferentially allocate area to represent the particular peripheral input sources that are proportionally most used. Alterations in cortical representations appear to underlie learning tasks dependent on the use of the behaviorally important peripheral inputs that they represent. The rules governing this cortical representational plasticity following manipulations of inputs, including learning, are increasingly well understood. In parallel with developments in the field of cortical map plasticity, studies of synaptic plasticity have characterized specific elementary forms of plasticity, including associative long-term potentiation and long-term depression of excitatory postsynaptic potentials. Investigators have made many important strides toward understanding the molecular underpinnings of these fundamental plasticity processes and toward defining the learning rules that govern their induction. The fields of cortical synaptic plasticity and cortical map plasticity have been implicitly linked by the hypothesis that synaptic plasticity underlies cortical map reorganization. Recent experimental and theoretical work has provided increasingly stronger support for this hypothesis. The goal of the current paper is to review the fields of both synaptic and cortical map plasticity with an emphasis on the work that attempts to unite both fields. A second objective is to highlight the gaps in our understanding of synaptic and cellular mechanisms underlying cortical representational plasticity.
Article
To investigate maintenance of training effects of a novel brain plasticity-based computerized cognitive training program in older adults after a 3-month no-contact period. Multisite, randomized, controlled, double-blind trial with two treatment groups. Communities in northern and southern California and Minnesota. Four hundred eighty-seven community-dwelling adults aged 65 and older without diagnosis of clinically significant cognitive impairment. Random assignment into a broadly available brain plasticity-based computerized cognitive training program experimental group or a novelty- and intensity-matched cognitive stimulation active control. Assessments at baseline, after training, and at 3 months. The primary outcome was a composite of auditory subtests of the Repeatable Battery for the Assessment of Neuropsychological Status. Secondary measures included trained task performance, standardized neuropsychological assessments of overall memory and attention, and participant-reported outcomes (PROs). A significant difference in improvement from baseline to 3-month follow-up was seen between the experimental training and control groups on the secondary composite of overall memory and attention, (P=.01, d=0.25), the trained processing-speed measure (P<.001, d=0.80), word list total recall (P=.004, d=0.28), letter-number sequencing (P=.003, d=0.29), and the cognitive subscale of PRO (P=.006, d=0.27). Previously significant improvements became nonsignificant at the 3-month follow-up for the primary outcome, two secondary measures of attention and memory, and several PROs. Narrative memory continued to show no advantage for the experimental group. Effect sizes from baseline to follow-up were generally smaller than effect sizes from baseline to posttraining. Training effects were maintained but waned over the 3-month no-contact period.
Article
Changed hearing occurs when sensorineural loss is acquired or increases, when hearing aids or cochlear implants are first acquired, when hearing aids are reprogrammed, and when cochlear implants are remapped. The changes affect speech perception-a process in which decisions about a talker's language output are made on the basis of sensory and contextual evidence, using knowledge and skill. The importance of spoken communication dictates speedy and optimal adaptation to changed hearing. Adaptation is a process in which the individual acquires new knowledge and modifies skill. Formal training provides the listener with the opportunity to enhance both knowledge and skill by spending time on speech perception tasks without the demands, constraints, uncertainties, and risks associated with everyday communication. Benefits of such training have been demonstrated in terms of improvement on trained tasks and talkers, generalization to untrained tasks and talkers, improvements in self-perceived competence, and reduction of self-perceived handicap. So far, however, we lack information on which aspects of training are responsible for benefit, which aspects of perception are changed, how individual differences interact with the foregoing, and whether these benefits translate into significantly increased participation and quality of life.
Article
Performance improvement during an hour of auditory perceptual training is accompanied by rapid physiological changes. These changes may reflect learning or simply task repetition independent of learning. We assessed the contribution of learning and task repetition to changes in auditory evoked potentials during a difficult speech identification task and an easy tone identification task. We posited that only task repetition effects would occur in the tone task but that task repetition and learning would interact in the speech task. Speech identification improved with practice (increased sensitivity d' with a constant response bias β). This behavioral improvement coincided with a decrease in the amplitude of sensory evoked responses (N1, P2) and a decrease in the amplitude of a slow wave (peak=320 ms after onset) over the left frontal and parietal sites. Results show rapid physiological changes associated with learning, distinct from changes related to task repetition.
Article
This study employed behavioral and electrophysiological measures to examine selective listening of concurrent auditory stimuli. Stimuli consisted of four compound sounds, each created by mixing a pure tone with filtered noise bands at a signal-to-noise ratio of +15 dB. The pure tones and filtered noise bands each contained two levels of pitch. Two separate conditions were created; the background stimuli varied randomly or were held constant. In separate blocks, participants were asked to judge the pitch of tones or the pitch of filtered noise in the compound stimuli. Behavioral data consistently showed lower sensitivity and longer response times for classification of filtered noise when compared with classification of tones. However, differential effects were observed in the peak components of auditory event-related potentials (ERPs). Relative to tone classification, the P1 and N1 amplitudes were enhanced during the more difficult noise classification task in both test conditions, but the peak latencies were shorter for P1 and longer for N1 during noise classification. Moreover, a significant interaction between condition and task was seen for the P2. The results suggest that the essential ERP components for the same compound auditory stimuli are modulated by listeners' focus on specific aspects of information in the stimuli.
Article
Speech scientists have long proposed that formant-exaggerated speech plays an important role in phonetic learning and language acquisition. However, there have been very little neurophysiological data on how the infant brain and adult brain respond to formant exaggeration in speech. We employed event-related potentials (ERPs) to investigate neural coding of formant-exaggerated speech sounds. Two synthetic i vowels were modeled after infant-directed speech data and presented in alternating blocks to test the effects of formant exaggeration. The fundamental frequencies of the two sounds were kept identical to avoid interference from exaggerated pitch level and range. For adult subjects, non-speech homologs were also created by using the center frequencies of the formants to additionally test whether the effects were speech-specific. In the infants (6 to 12-month olds), ERP waveforms showed significantly enhanced N250 and sustaining negativity responses for processing formant-exaggerated speech. In adults, enhancement was observed in the N100 component for the speech stimuli but not the homologous non-speech sounds. Collectively, these results provide the first evidence that formant expansion in infant-directed speech enhances neural activities for phonetic encoding, which may facilitate phonetic learning and language acquisition regardless of the age factor [Zhang et al. (2009). Neuroimage 46, 226-240].
Article
To investigate the efficacy of a novel brain plasticity-based computerized cognitive training program in older adults and to evaluate the effect on untrained measures of memory and attention and participant-reported outcomes. Multisite randomized controlled double-blind trial with two treatment groups. Communities in northern and southern California and Minnesota. Community-dwelling adults aged 65 and older (N=487) without a diagnosis of clinically significant cognitive impairment. Participants were randomized to receive a broadly-available brain plasticity-based computerized cognitive training program (intervention) or a novelty- and intensity-matched general cognitive stimulation program modeling treatment as usual (active control). Duration of training was 1 hour per day, 5 days per week, for 8 weeks, for a total of 40 hours. The primary outcome was a composite score calculated from six subtests of the Repeatable Battery for the Assessment of Neuropsychological Status that use the auditory modality (RBANS Auditory Memory/Attention). Secondary measures were derived from performance on the experimental program, standardized neuropsychological assessments of memory and attention, and participant-reported outcomes. RBANS Auditory Memory/Attention improvement was significantly greater (P=.02) in the experimental group (3.9 points, 95% confidence interval (CI)=2.7-5.1) than in the control group (1.8 points, 95% CI=0.6-3.0). Multiple secondary measures of memory and attention showed significantly greater improvements in the experimental group (word list total score, word list delayed recall, digits backwards, letter-number sequencing; P<.05), as did the participant-reported outcome measure (P=.001). No advantage for the experimental group was seen in narrative memory. The experimental program improved generalized measures of memory and attention more than an active control program.
Article
At high presentation levels, normally aided ears yield better performance for speech identification than normally unaided ears, while at low presentation levels the converse is true [S. Gatehouse, J. Acoust. Soc. Am. 86, 2103-2106 (1989)]. To explain this process further, the speech identification abilities of four subjects with bilateral symmetric sensorineural hearing impairment were investigated following provision of a single hearing aid. Results showed significant increases in the benefit from amplifying speech in the aided ear, but not in the control ear. In addition, a headphone simulation of the unaided condition for the fitted ear shows a decrease in speech identification. The benefits from providing a particular frequency spectrum do not emerge immediately, but over a time course of at least 6-12 weeks. The findings support the existence of perceptual acclimatization effects, and call into question short-term methods of hearing aid evaluation and selection by comparative speech identification tests.
Article
This study investigated whether the P3 AERP could be used to reflect behavioral changes resulting from therapeutic intervention in a group of children with central auditory processing disorders (CAPDs). Results showed a significant decrease in P3 latency, along with a significant increase in P3 amplitude, following a structured treatment program. No changes occurred in either the CAPD control group or in the normal control group. These results suggest that the P3 AERP latency and amplitude measures are sensitive to changes in clinical status following a treatment program.
Article
Associative learning produces conditioned stimulus (CS)-specific plasticity of frequency receptive fields (RFs) in the auditory cortex; responses to the CS frequency are increased, whereas responses to other frequencies are decreased. This study determined the effects of habituation on the RF of neurons in the auditory cortex of the guinea pig (Cavia porcellus). One frequency was presented repeatedly (REP) followed by redetermination of the RF. After REP, 26/36 (72%) RFs exhibited a substantial reduction (70-75%) of response to the repeated frequency, and this was highly specific (bandwidth less than 0.125 octave). This RF plasticity involves an initial decrease in response during REP but does not require attenuated responses at the end of REP. Incubation (i.e., development over time after cessation of REP) and long-term frequency-specific effects are evident. Thus, habituation induces a specific change in the processing of frequency information rather than a general reduction in responsivity.
Article
The need for a simply applied quantitative assessment of handedness is discussed and some previous forms reviewed. An inventory of 20 items with a set of instructions and response- and computational-conventions is proposed and the results obtained from a young adult population numbering some 1100 individuals are reported. The separate items are examined from the point of view of sex, cultural and socio-economic factors which might appertain to them and also of their inter-relationship to each other and to the measure computed from them all. Criteria derived from these considerations are then applied to eliminate 10 of the original 20 items and the results recomputed to provide frequency-distribution and cumulative frequency functions and a revised item-analysis. The difference of incidence of handedness between the sexes is discussed.
Article
The P300 component of the human average evoked potential has been associated with a host of stimulus and S variables, such as information delivery and stimulus salience. P300 is emitted by the brain in response to either attended events that are surprising or to unattended events that produce orienting. P300 does not appear to be a real-time index of signal (target) selection, since attended low-probability nonsignals also result in P300 and its latency is too long. P300 further appears to be independent of response selection; its latency therefore may or may not correlate with RT, depending on the experimental context. P300 latency does appear to index stimulus evaluation time in that it is not emitted until the stimulus has been cognitively evaluated. P300 amplitude appears sensitive to manipulations of perceptual limited capacity but not sensitive to manipulations of motor limited capacity. It has been proposed that P300's functional role in human information processing is the updating of neurocognitive models concerning future events, although other functions have also been proposed. (5 p ref) (PsycINFO Database Record (c) 2012 APA, all rights reserved)