Integration of auditory and visual cues in spatial navigation under normal and impaired viewing conditions.

Auditory landmarks can contribute to spatial updating during navigation with vision. Whereas large inter-individual differences have been identified in how navigators combine auditory and visual landmarks, it is still unclear under what circumstances audition is used. Further, whether or not individuals optimally combine auditory cues with visual cues to decrease the amount of perceptual uncertainty, or variability, has not been well-documented.

The addition of a spatial auditory cue improves spatial updating in a virtual reality navigation task.

Auditory cues are integrated with vision and body-based self-motion cues for motion perception, balance, and gait, though limited research has evaluated their effectiveness for navigation. Here, we tested whether an auditory cue co-localized with a visual target could improve spatial updating in a virtual reality homing task. Participants navigated a triangular homing task with and without an easily localizable spatial audio signal co-located with the home location.

Effects of older age on visual and self-motion sensory cue integration in navigation.

Older adults demonstrate impairments in navigation that cannot be explained by general cognitive and motor declines. Previous work has shown that older adults may combine sensory cues during navigation differently than younger adults, though this work has largely been done in dark environments where sensory integration may differ from full-cue environments. Here, we test whether aging adults optimally combine cues from two sensory systems critical for navigation: vision (landmarks) and body-based self-motion cues.

Subcostal versus right lateral ultrasound measurements of inferior vena cava: Measurements obtained from these two views are not equivalent in non-ICU patients.

Objective: The objective of this study is to assess concordance between the subcostal and right lateral view for ultrasonographic inferior vena cava measurements including the end-inspiratory diameter, end-expiratory diameter and respiratory variation represented by the caval index in spontaneously breathing healthy adults.

Methods: We recruited a convenience sample of 33 healthy adults. A phased array ultrasound probe was used to obtain inferior vena cava measurements from a subcostal view in the sagittal plane and from a right lateral view in the coronal plane with B-mode ultrasound.

Reliability of Vestibular Perceptual Threshold Testing About the Yaw Axis.

Objectives: Vestibular reflexes have traditionally formed the cornerstone of vestibular evaluation, but perceptual tests have recently gained attention for use in research studies and potential clinical applications. However, the unknown reliability of perceptual thresholds limits their current importance. This is addressed here by establishing the test-retest reliability of vestibular perceptual testing.

Frequency-dependent integration of auditory and vestibular cues for self-motion perception.

Recent evidence has shown that auditory information may be used to improve postural stability, spatial orientation, navigation, and gait, suggesting an auditory component of self-motion perception. To determine how auditory and other sensory cues integrate for self-motion perception, we measured motion perception during yaw rotations of the body and the auditory environment. Psychophysical thresholds in humans were measured over a range of frequencies (0.

Geographic Disparities in US Veterans' Access to Cochlear Implant Care Within the Veterans Health Administration System.

Importance: Veterans are at high risk for developing sensorineural hearing loss leading to cochlear implant (CI) candidacy; however, the ability to care for these patients is limited by the number and location of Veterans Health Administration (VHA) facilities that provide specialized CI services.

Objective: To investigate geographic disparities in access to CI care within the VHA system for US veterans.

Design, Setting, And Participants: An analysis of census tract-level data including US veterans was conducted using the nationwide American Community Survey data collected by the US Census Bureau from January to December 2016, which were accessed in 2017.

Relationship between vestibular sensitivity and multisensory temporal integration.

A single event can generate asynchronous sensory cues due to variable encoding, transmission, and processing delays. To be interpreted as being associated in time, these cues must occur within a limited time window, referred to as a "temporal binding window" (TBW). We investigated the hypothesis that vestibular deficits could disrupt temporal visual-vestibular integration by determining the relationships between vestibular threshold and TBW in participants with normal vestibular function and with vestibular hypofunction.

The contribution of cochlear implants to postural stability.

Objectives: To determine whether spatial auditory cues provided by cochlear implants can improve postural balance in adults with severe deafness.

Methods: In the presence of spatial white noise, 13 adult cochlear implantees wore head and lumbar-mounted inertial sensors while standing in the dark for 30 seconds in two auditory conditions: hearing assistive devices on and off.

Results: Stability was improved with implants on (aided condition) compared to off (unaided condition) with respect to differences in mean head velocity (Cohen's d = 0.

Localization performance correlates with binaural fusion for interaurally mismatched vocoded speech.

Bilateral cochlear implant users often have difficulty fusing sounds from the two ears into a single percept. However, measuring fusion can be difficult, particularly with cochlear implant users who may have no reference for a fully fused percept. As a first step to address this, this study examined how localization performance of normal hearing subjects relates to binaural fusion.

The Effect of Hearing Aids and Cochlear Implants on Balance During Gait.

Hypothesis: Auditory input in people with hearing impairment will improve balance while walking.

Background: Auditory input is increasingly recognized as an additional input for balance. Several studies have found auditory cues to improve static balance measured on a sway platform.

Binaural pitch fusion: Comparison of normal-hearing and hearing-impaired listeners.

Binaural pitch fusion is the fusion of dichotically presented tones that evoke different pitches between the ears. In normal-hearing (NH) listeners, the frequency range over which binaural pitch fusion occurs is usually <0.2 octaves.

Improvements in Gait With Hearing Aids and Cochlear Implants.

Objective: To evaluate whether wearing auditory assistive devices can improve gait and dynamic balance.

Patients: Three adult users of bilateral hearing assistive devices: one with cytomegalovirus exposure wearing cochlear implants, one with Ménière's disease wearing hearing aids, and one with presbystasis wearing hearing aids.

Intervention: Rehabilitative intervention involved participants performing gait and dynamic posture tasks with and without their hearing assistive devices.

Taste Disturbance Due to Cochlear Implant Stimulation.

Objective: To characterize stimulation of taste fibers in the facial nerve following cochlear implantation.

Patient: A 34-year old presented with reversible dysgeusia following activation of a cochlear implant.

Intervention: Reprogramming targeted to specific offending electrodes reduced symptom intensity.

Unilateral spectral and temporal compression reduces binaural fusion for normal hearing listeners with cochlear implant simulations.

Patients with single sided deafness have recently begun receiving cochlear implants in their deaf ear. These patients gain a significant benefit from having a cochlear implant. However, despite this benefit, they are considerably slower to develop binaural abilities such as summation compared to bilateral cochlear implant patients.