Reduced digit spans and ear dominance using dichotic digits in bimodal cochlear-implant users.

Bimodal stimulation, a cochlear implant (CI) in one ear and a hearing aid (HA) in the other, provides highly asymmetrical inputs. To understand how asymmetry affects perception and memory, forward and backward digit spans were measured in nine bimodal listeners. Spans were unchanged from monotic to diotic presentation; there was an average two-digit decrease for dichotic presentation with some extreme cases of decreases to zero spans. Interaurally asymmetrical decreases were not predicted based on the device or better-functioning ear. Therefore, bimodal listeners can demonstrate a strong ear dominance, diminishing memory recall dichotically even when perception was intact monaurally.

A new paradigm for assessing postural stability.

BACKGROUND: The sensory organization test (SOT) is an established and effective method for assessing postural stability and determining fall risk. SOT equilibrium scores are derived from the relationship between an individual's peak sway amplitude and a standard, theoretically-derived normal limits of stability (tLOS). Determining an individual's postural stability and fall risk based on this one-size-fits-all tLOS may overestimate functional equilibrium scores and underestimate fall risk when personal stability limits (pLOS) are reduced. RESEARCH QUESTION: The purpose of this study is to investigate whether LOS measured from a group of healthy adults is different from the tLOS, and whether SOT equilibrium scores are significantly different when calculated using pLOS versus the standard tLOS. METHODS: Sixty healthy volunteers were recruited into three age-groups: young (18-39), middle-aged (40-64), and elderly (65-80), with 10 males and 10 females in each age-group. Outcome measures included SOT and LOS. Additional measures o balance perception and functional mobility were obtained including the Activities Balance Confidence (ABC) scale and the timed-up-and-go test (TUG). The tLOS and pLOS were used to calculate standard (tSOT) and personalized (pSOT) equilibrium scores. RESULTS: The mean pLOS from the group of healthy adults was significantly lower than the tLOS. Consequently, the pSOT equilibrium scores were significantly lower than the standard SOT scores derived using the tLOS. SIGNIFICANCE: Individual measures of LOS are significantly lower than theoretical estimates of the LOS in healthy adults. This suggests that use of tLOS in the calculation of SOT equilibrium scores often overestimates postural stability and may have implications for the determination of fall risk.

Maximizing Cochlear Implant Outcomes with Short-Term Aural Rehabilitation.

BACKGROUND: Increasing numbers of adults are receiving cochlear implants (CIs) and many achieve high levels of speech perception and improved quality of life. However, a proportion of implant recipients still struggle due to limited speech recognition and/or greater communication demands in their daily lives. For these individuals a program of aural rehabilitation (AR) has the potential to improve outcomes. PURPOSE: The study investigated the effects of a short-term AR intervention on speech recognition, functional communication, and psychosocial outcomes in post lingually deafened adult CI users. RESEARCH DESIGN: The experimental design was a multisite clinical study with participants randomized to either an AR treatment or active control group. Each group completed 6 weekly 90-minute individual treatment sessions. Assessments were completed pretreatment, 1 week and 2 months post-treatment. STUDY SAMPLE: Twenty-five post lingually deafened adult CI recipients participated. AR group: mean age 66.2 (48-80); nine females, four males; months postactivation 7.7 (3-16); mean years severe to profound deafness 18.4 (2-40). Active control group: mean age 62.8 (47-85); eight females, four males; months postactivation 7.0 (3-13); mean years severe to profound deafness 18.8 (1-55). INTERVENTION: The AR protocol consisted of auditory training (words, sentences, speech tracking), and psychosocial counseling (informational and communication strategies). Active control group participants engaged in cognitive stimulation activities (e.g., crosswords, sudoku, etc.). DATA COLLECTION AND ANALYSIS: Repeated measures ANOVA or analysis of variance, MANOVA or multivariate analysis of variance, and planned contrasts were used to compare group performance on the following measures: CasperSent; Hearing Handicap Inventory; Nijmegen Cochlear Implant Questionnaire; Client Oriented Scale of Improvement; Glasgow Benefit Inventory. RESULTS: The AR group showed statistically significant improvements on speech recognition performance, psychosocial function, and communication goals with no significant improvement seen in the control group. The two groups were statistically equivalent on all outcome measures at preassessment. The robust improvements for the AR group were maintained at 2 months post-treatment. CONCLUSION: Results of this clinical study provide evidence that a short-term AR intervention protocol can maximize outcomes for adult post lingually deafened CI users. The impact of this brief multidimensional AR intervention to extend CI benefit is compelling, and may serve as a template for best practices with adult CI users.

Assessment of Reliability and Validity of the Cochlear Implant Skills Review: A New Measure to Evaluate Cochlear Implant Users' Device Skills and Knowledge.

Purpose The Cochlear Implant Skills Review (CISR) was developed as a measure of cochlear implant (CI) users' skills and knowledge regarding device use. This study aimed to determine intra- and interrater reliability and agreement and establish construct validity for the CISR. Method In this study, the CISR was developed and administered to a cohort of 30 adult CI users. Participants included new CI users with less than 1 year of CI experience and experienced CI users with greater than 1 year of CI experience. The CISR administration required participants to demonstrate skills using the various features of their CI processors. Intra- and interrater reliability were assessed using intraclass correlation coefficients, agreement was assessed using Cohen's kappa, and construct validity was assessed by relating CISR performance to duration of CI use. Results Overall reliability for the entire instrument was 92.7%. Inter- and intrarater agreement were generally substantial or higher. Duration of CI use was a significant predictor of CISR performance. Conclusions The CISR is a reliable and valid assessment measure of device skills and knowledge for adult CI users. Clinicians can use this tool to evaluate areas of needed instruction and counseling and to assess users' skills over time.

Bimodal Cochlear Implant Listeners' Ability to Perceive Minimal Audible Angle Differences.

BACKGROUND: Bilateral inputs should ideally improve sound localization and speech understanding in noise. However, for many bimodal listeners [i.e., individuals using a cochlear implant (CI) with a contralateral hearing aid (HA)], such bilateral benefits are at best, inconsistent. The degree to which clinically available HA and CI devices can function together to preserve interaural time and level differences (ITDs and ILDs, respectively) enough to support the localization of sound sources is a question with important ramifications for speech understanding in complex acoustic environments. PURPOSE: To determine if bimodal listeners are sensitive to changes in spatial location in a minimum audible angle (MAA) task. RESEARCH DESIGN: Repeated-measures design. STUDY SAMPLE: Seven adult bimodal CI users (28-62 years). All listeners reported regular use of digital HA technology in the nonimplanted ear. DATA COLLECTION AND ANALYSIS: Seven bimodal listeners were asked to balance the loudness of prerecorded single syllable utterances. The loudness-balanced stimuli were then presented via direct audio inputs of the two devices with an ITD applied. The task of the listener was to determine the perceived difference in processing delay (the interdevice delay [IDD]) between the CI and HA devices. Finally, virtual free-field MAA performance was measured for different spatial locations both with and without inclusion of the IDD correction, which was added with the intent to perceptually synchronize the devices. RESULTS: During the loudness-balancing task, all listeners required increased acoustic input to the HA relative to the CI most comfortable level to achieve equal interaural loudness. During the ITD task, three listeners could perceive changes in intracranial position by distinguishing sounds coming from the left or from the right hemifield; when the CI was delayed by 0.73, 0.67, or 1.7 msec, the signal lateralized from one side to the other. When MAA localization performance was assessed, only three of the seven listeners consistently achieved above-chance performance, even when an IDD correction was included. It is not clear whether the listeners who were able to consistently complete the MAA task did so via binaural comparison or by extracting monaural loudness cues. Four listeners could not perform the MAA task, even though they could have used a monaural loudness cue strategy. CONCLUSIONS: These data suggest that sound localization is extremely difficult for most bimodal listeners. This difficulty does not seem to be caused by large loudness imbalances and IDDs. Sound localization is best when performed via a binaural comparison, where frequency-matched inputs convey ITD and ILD information. Although low-frequency acoustic amplification with a HA when combined with a CI may produce an overlapping region of frequency-matched inputs and thus provide an opportunity for binaural comparisons for some bimodal listeners, our study showed that this may not be beneficial or useful for spatial location discrimination tasks. The inability of our listeners to use monaural-level cues to perform the MAA task highlights the difficulty of using a HA and CI together to glean information on the direction of a sound source.

A peer mentor training program for aural rehabilitation.

This article describes a new training program at Gallaudet University that aims to prepare peer mentors to work under the supervision of hearing-health professionals in the area of aural rehabilitation (AR). The paucity of AR programs for consumers with hearing loss in the United States has been documented. The peer mentor training program is an attempt to harness the energies, skills, and knowledge of people with hearing loss; to expand them through a program of academic and experiential learning; and to put them to work in audiologic practices and other hearing-health care settings in order to improve the quality and quantity of AR available to consumers. A peer mentor training curriculum is described, and the current status of the educational program is reported. Initial anecdotal evidence suggests that the program has the potential to contribute to the development of a more comprehensive model of AR service delivery.