Anu Sharma

Anu Sharma
University of Colorado Boulder | CUB · Department of Speech, Language and Hearing Sciences (SLHS)

About

98
Publications
23,826
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
8,388
Citations
Citations since 2017
12 Research Items
3386 Citations
20172018201920202021202220230100200300400500600
20172018201920202021202220230100200300400500600
20172018201920202021202220230100200300400500600
20172018201920202021202220230100200300400500600

Publications

Publications (98)
Article
Full-text available
Aim To investigate mask use and the difficulties it may pose during communication in healthcare settings. Methods A survey utilizing a series of Likert scales was administered. Mask use challenges between clinicians and their patients were examined in the domains of communication, listening effort, cognition, and rehabilitation. Results Across 24...
Article
Hypothesis: We hypothesized that children with cochlear implants (CIs) who demonstrate cross-modal reorganization by vision also demonstrate cross-modal reorganization by somatosensation and that these processes are interrelated and impact speech perception. Background: Cross-modal reorganization, which occurs when a deprived sensory modality's cor...
Article
Full-text available
Objective The benefit of hearing aids as a clinical intervention strategy for children with Auditory Neuropathy Spectrum Disorder (ANSD) remains controversial. The goal of this study was to determine whether amplification through hearing aid use increased cortical phase synchrony in children with ANSD. Design Using inter-trial coherence (ITC) of t...
Article
Full-text available
Purpose Auditory threshold estimation using the auditory brainstem response or auditory steady state response is limited in some populations (e.g., individuals with auditory neuropathy spectrum disorder [ANSD] or those who have difficulty remaining still during testing and cannot tolerate general anesthetic). However, cortical auditory evoked poten...
Article
Full-text available
Recent research has demonstrated frontal cortical involvement to co-occur with visual re-organization, suggestive of top-down modulation of cross-modal mechanisms. However, it is unclear whether top-down modulation of visual re-organization takes place in mild hearing loss, or is dependent upon greater degrees of hearing loss severity. Thus, the pu...
Article
Full-text available
Age-related hearing loss (ARHL) is associated with cognitive decline as well as structural and functional brain changes. However, the mechanisms underlying neurocognitive deficits in ARHL are poorly understood and it is unclear whether clinical treatment with hearing aids may modify neurocognitive outcomes. To address these topics, cortical visual...
Article
Full-text available
Deprived of sensory input, as in deafness, the brain tends to reorganize. Cross-modal reorganization occurs when cortices associated with deficient sensory modalities are recruited by other, intact senses for processing of the latter’s sensory input. Studies have shown that this type of reorganization may affect outcomes when sensory stimulation is...
Article
Full-text available
This article summarizes the presentations and recommendations of the tenth annual American Geriatrics Society and National Institute on Aging Bench‐to‐Bedside research conference, “Sensory Impairment and Cognitive Decline,” on October 2–3, 2017, in Bethesda, Maryland. The risk of impairment in hearing, vision, and other senses increases with age, a...
Article
Full-text available
Under conditions of profound sensory deprivation, the brain has the propensity to reorganize. For example, intact sensory modalities often recruit deficient modalities’ cortices for neural processing. This process is known as cross-modal reorganization and has been shown in congenitally and profoundly deaf patients. However, much less is known abou...
Article
Full-text available
Objective: Auditory neuropathy spectrum disorder (ANSD) affects approximately 5–15% of children with sensorineural hearing loss (SNHL). ANSD is characterized by the presence of otoacoustic emissions (OAE) and an absent or abnormal auditory brainstem response (ABR). The purpose of this study was to investigate the prognostic value of slow-rate ABR i...
Article
Full-text available
Measures of visual cortical development in children demonstrate high variability and inconsistency throughout the literature. This is partly due to the specificity of the visual system in processing certain features. It may then be advantageous to activate multiple cortical pathways in order to observe maturation of coinciding networks. Visual stim...
Data
Visual stimuli. Visual stimuli for the experiment consisted of a high contrast sinusoidal concentric grating that transitioned into a radially modulated grating or circle-star pattern. Adapted from Doucet et al. (2005, 2006).
Article
Full-text available
Hypothesis: The purpose of this study was to examine changes in cortical development and neuroplasticity in a child with single-sided deafness (SSD) before and after cochlear implantation (CI). Background: The extent to which sensory pathways reorganize in childhood SSD is not well understood and there is currently little evidence demonstrating...
Article
Full-text available
We review evidence for cross-modal cortical re-organization in clinical populations with hearing loss. Cross-modal plasticity refers to the ability for an intact sensory modality (e.g., vision or somatosensation) to recruit cortical brain regions from a deprived sensory modality (e.g., audition) to carry out sensory processing. We describe evidence...
Article
Full-text available
Background: Visual cross-modal re-organization is a neurophysiological process that occurs in deafness. The intact sensory modality of vision recruits cortical areas from the deprived sensory modality of audition. Such compensatory plasticity is documented in deaf adults and animals, and is related to deficits in speech perception performance in c...
Data
Speech Perception Performance in Background Noise (BKB-SIN) and VEP N1 Latency Data for Fig 5. (A) Subject numbers. (B) Corresponding mean BKB-SIN threshold values. (C) VEP N1 latency (in milliseconds) as recorded from the right temporal region of interest (ROI) for the cochlear-implanted (CI) children. (XLSX)
Article
Full-text available
We review evidence for a high degree of neuroplasticity of the central auditory pathways in early childhood, citing evidence of studies of the P1 and N1 cortical auditory evoked potentials in congenitally deaf children receiving cochlear implants at different ages during childhood, children with auditory neuropathy spectrum disorder and children wi...
Article
Full-text available
Cortical development is dependent to a large extent on stimulus-driven input. Auditory Neuropathy Spectrum Disorder (ANSD) is a recently described form of hearing impairment where neural dys-synchrony is the predominant characteristic. Children with ANSD provide a unique platform to examine the effects of asynchronous and degraded afferent stimulat...
Article
Full-text available
We focus on principal differential analysis (PDA; Ramsay 1996) of functional data for obtaining a low-dimensional representation of a collection of curves. PDA assumes there exists a linear differential operator that results in the zero-function when it is applied to each of the data curves, or equivalently, that the curves belong to a low dimensio...
Article
Full-text available
Deafness alters the normal connectivity needed for an optimally functioning sensory system—resulting in deficits in speech perception and cognitive functioning. Cochlear implants have been a highly successful intervention because they bypass cochlear damage and directly stimulate the auditory nerve and brain, taking advantage of high degree of neur...
Chapter
Full-text available
Congenital deafness results in a lack of input to the auditory system, hence dramatically altering cortical connectivity and development. Cochlear implants bypass the damaged cochlea by directly stimulating the central nervous system, providing a window into the development of the central auditory system. Converging evidence from studies of deaf an...
Article
Full-text available
Cortical development is dependent on extrinsic stimulation. As such, sensory deprivation, as in congenital deafness, can dramatically alter functional connectivity and growth in the auditory system. Cochlear implants ameliorate deprivation-induced delays in maturation by directly stimulating the central nervous system, and thereby restoring auditor...
Article
Full-text available
Objective: We examined 1) auditory cortical organization and functioning, and 2) variability in cortical responses in a paediatric patient with unilateral auditory neuropathy spectrum disorder (ANSD). Study design: Measures of high-density EEG (including cortical auditory evoked potentials (CAEPs)), dipole and current-density analyses, independent...
Article
Full-text available
Cortical cross-modal re-organization, or recruitment of auditory cortical areas for visual processing, has been well-documented in deafness. However, the degree of sensory deprivation necessary to induce such cortical plasticity remains unclear. We recorded visual evoked potentials (VEP) using high-density electroencephalography in nine persons wit...
Article
Children with language-learning problems (LLP) often demonstrate auditory processing deficits on tasks using nonlinguistic stimuli, which may indicate an underlying auditory processing disorder (APD) that leads to delayed language skills. However, recent studies of event-related potentials provide evidence that APD is the result of, rather than the...
Article
Full-text available
Cortical development is dependent on extrinsic stimulation. As such, sensory deprivation, as in congenital deafness, can dramatically alter functional connectivity and growth in the auditory system. Cochlear implants ameliorate deprivation-induced delays in maturation by directly stimulating the central nervous system, and thereby restoring auditor...
Article
Although brainstem dys-synchrony is a hallmark of children with auditory neuropathy spectrum disorder (ANSD), little is known about how the lack of neural synchrony manifests at more central levels. We used time-frequency single-trial EEG analyses (i.e., inter-trial coherence; ITC), to examine cortical phase synchrony in children with normal hearin...
Article
Full-text available
Hearing loss has been linked to many types of cognitive decline in adults, including an association between hearing loss severity and dementia. However, it remains unclear whether cortical re-organization associated with hearing loss occurs in early stages of hearing decline and in early stages of auditory processing. In this study, we examined com...
Article
Full-text available
First, we review the development and plasticity of the central auditory pathways in infants and children with hearing loss who are fitted with cochlear implants (CIs). Second, we describe case studies demonstrating the clinical utility of the P1 central auditory evoked potential (CAEP) for evaluating cortical auditory maturation in the rapidly incr...
Article
Full-text available
Objective: We examined cortical auditory development and behavioral outcomes in children with ANSD fitted with cochlear implants (CI). Design: Cortical maturation, measured by P1 cortical auditory evoked potential (CAEP) latency, was regressed against scores on the infant toddler meaningful auditory integration scale (IT-MAIS). Implantation age...
Chapter
Cortical development depends on both intrinsic and extrinsic (or stimulus-driven) factors. In this chapter, the impact of childhood deafness on two modalities important for everyday communication, audition and vision, is discussed. Sensory deprivation from birth, as in congenital deafness, alters the normal growth and connectivity of the central au...
Article
Full-text available
The developing auditory cortex is highly plastic. As such, the cortex is both primed to mature normally and at risk for reorganizing abnormally, depending upon numerous factors that determine central maturation. From a clinical perspective, at least two major components of development can be manipulated: (1) input to the cortex and (2) the timing o...
Article
Full-text available
The goal of this report was to ascertain the efficacy of the P1 cortical auditory evoked potential (CAEP) biomarker as an objective tool to assist in the evaluation of cochlear implant (CI) candidacy in children with a radiological diagnosis of cochlear nerve deficiency (CND). Retrospective case study review of audiological and radiological finding...
Article
Cortical development is dependent on stimulus-driven learning. The absence of sensory input from birth, as occurs in congenital deafness, affects normal growth and connectivity needed to form a functional sensory system, resulting in deficits in oral language learning. Cochlear implants bypass cochlear damage by directly stimulating the auditory ne...
Article
Full-text available
The absence of hearing, as in congenital deafness, affects normal development of the auditory brain resulting in deficits in spoken language. Cochlear implants provide direct stimulation to the central auditory nervous system of hearing impaired children allowing cortical development to progress. However, implantation needs to take place within a b...
Chapter
Full-text available
Cortical development is dependent on both intrinsic and extrinsic (stimulus-driven) factors. The absence of sensory input from birth, as in congenital deafness, inhibits the normal growth and connectivity needed to form a functional sensory system, resulting in deficits in spoken language. Cochlear implants (CIs) bypass peripheral cochlear damage,...
Article
Full-text available
Neuroplasticity can be defined as the ability of the nervous system to respond to intrinsic or extrinsic stimuli by reorganizing its structure, function and connections. Major advances in the understanding of neuroplasticity have to date yielded few established interventions. To advance the translation of neuroplasticity research towards clinical a...
Article
Full-text available
The P1 component of the cortical auditory evoked potential (CAEP) shows clearly documented age-related decreases in latency and changes in morphology in normal hearing children, providing a biomarker for development of the auditory cortical pathways in humans. In hearing-impaired children, auditory deprivation may affect the normal age-related chan...
Article
Full-text available
Unlabelled: OBJECTIVE. Auditory neuropathy spectrum disorder (ANSD) affects approximately 10% of patients with sensorineural hearing loss. While many studies report abnormalities at the level of the cochlea, auditory nerve, and brainstem in children with ANSD, much less is known about their cortical development. We examined central auditory matura...
Article
Full-text available
Standard clinical audiologic assessments have proven useful in the detection and diagnosis of auditory neuropathy spectrum disorder (ANSD). However, beyond initial diagnosis, clinicians have fewer tools to appropriately manage infants and young children with ANSD. While cortical auditory evoked potentials (CAEP) are not currently used routinely in...
Article
Full-text available
Children who experience long periods of auditory deprivation are susceptible to large-scale reorganization of auditory cortical areas responsible for the perception of speech and language. One consequence of this reorganization is that integration of combined auditory and visual information may be altered after hearing is restored with a cochlear i...
Article
Source localization of electrical activity in the brain can be greatly improved by testing the experimental variability in the signals being localized. The most widely used method for extracting evoked potential (EP) signals from the EEG is averaging. Averaging multiple EEG epochs suppresses background noise, revealing EP components that are time a...
Article
Full-text available
Unlabelled: A basic tenet of developmental neurobiology is that certain areas of the cortex will re-organize, if appropriate stimulation is withheld for long periods. Stimulation must be delivered to a sensory system within a narrow window of time (a sensitive period) if that system is to develop normally. In this article, we will describe age cut...
Article
Unlabelled: The mirror neuron system (MNS) is a trimodal system composed of neuronal populations that respond to motor, visual, and auditory stimulation, such as when an action is performed, observed, heard or read about. In humans, the MNS has been identified using neuroimaging techniques (such as fMRI and mu suppression in the EEG). It reflects...
Article
The aim of this study was to determine whether, in young children, a cortical neurophysiologic representation of the voicing status of a stop consonant could be found in the absence of the N1 component in the cortical auditory evoked potential (CAEP). In adults, a 'double-on' N1 response is often considered a cortical marker of VOT representation....
Article
Congenital deafness leads to atypical organization of the auditory nervous system. However, the extent to which auditory pathways reorganize during deafness is not well understood. We recorded cortical auditory evoked potentials in normal hearing children and in congenitally deaf children fitted with cochlear implants. High-density EEG and source m...
Article
Full-text available
A basic finding in developmental neurophysiology is that some areas of the cortex cortical areas will reorganize following a period of stimulus deprivation. In this review, we discuss mainly electroencephalography (EEG) studies of normal and deprivation-induced abnormal development of the central auditory pathways in children and in animal models....
Article
Unlabelled: In normal-hearing children the latency of the P1 component of the cortical evoked response to sound varies as a function of age and, thus, can be used as a biomarker for maturation of central auditory pathways. We assessed P1 latency in 245 congenitally deaf children fit with cochlear implants following various periods of auditory depr...
Conference Paper
Full-text available
Currently researchers interested in developing new signal processing algorithms for commercially available cochlear implants must rely on coding these algorithms in low-level assembly language. We propose a personal digital assistant (PDA) based research platform for developing and testing in real-time new signal processing strategies for cochlear...
Article
Full-text available
The aim of this study was to determine whether children who received early, simultaneous, bilateral cochlear implants showed more rapid development of the central auditory pathways compared to children who received early, sequential, bilateral implants. In 20 children, over the first 15 months following bilateral implantation, we assessed longitudi...
Article
Previous research suggests prelingually deaf individuals who receive a cochlear implant early in childhood develop better oral communication skills than those who receive their implant later. However, the mechanisms influencing this sensitive period are not well understood. This investigation explores one possible mechanism limiting the sensitive p...
Article
Full-text available
To examine the time course of maturation of P1 latencies in infant sequential and simultaneous bilateral cochlear implant recipients. Retrospective case series. Pediatric collaborative cochlear implant program. Four children who received bilateral cochlear implants prior to age 2 years. Cortical auditory evoked potential was completed to determine...
Article
Full-text available
Undergraduate ENT teaching provides junior doctors with skills and knowledge useful for the practice of medicine. However, ENT has been removed from the curriculum of nine of the 29 medical schools in the United Kingdom, as it was not deemed relevant to general medical practice. A telephone survey was performed of 20 senior house officers working i...
Article
To examine maturation of the central auditory pathways in children with language-based learning problems (LP). Cortical auditory evoked potentials (CAEPs) recorded from 26 children with LP were compared to CAEPs recorded from 38 typical children. CAEP responses were recorded in response to a speech sound, /uh/, which was presented in a stimulus tra...
Article
To compare two methods of minimizing cochlear implant artifact in cortical auditory evoked potential (CAEP) recordings. Two experiments were conducted. In the first, we assessed the use of independent component analysis (ICA) as a pre-processing filter. In the second, we explored the use of an optimized differential reference (ODR) for minimizing a...
Article
Full-text available
A common finding in developmental neurobiology is that stimulation must be delivered to a sensory system within a narrow window of time (a sensitive period) during development in order for that sensory system to develop normally. Experiments with congenitally deaf children have allowed us to establish the existence and time limits of a sensitive pe...
Article
Full-text available
We used the latency of the P1 cortical auditory-evoked potential (CAEP) as a biomarker for the development of central auditory pathways in three children who received intervention through hearing aids and/or cochlear implants. Our goal was to examine the clinical feasibility of using the latency of the P1 CAEP as an objective tool to evaluate wheth...
Article
We examined the longitudinal development of the cortical auditory evoked potential (CAEP) in 21 children who were fitted with unilateral cochlear implants and in two children who were fitted with bilateral cochlear implants either before age 3.5 years or after age 7 years. The age cut-offs (<3.5 years for early-implanted and >7 years for late-impla...
Article
This study examined morphological changes in the cortical auditory evoked potential (CAEP) waveform as a function of varying stimulation rate. Stimuli were presented in a paradigm which indirectly assesses the refractory properties of the underlying neuronal generators. CAEPs were recorded in 50 normal-hearing children (3-12 years) and 10 young adu...
Article
Full-text available
To examine the relationship between the maturation of central auditory pathways and the development of canonical (speechlike) babbling in infants with cochlear implants. Comparison of the latencies of the P1 cortical auditory evoked potential and vocalizations produced by subjects before they were fitted with a cochlear implant and at several time...
Article
The aim of the present experiment was to assess the consequences of cochlear implantation at different ages on the development of the human central auditory system. Our measure of the maturity of central auditory pathways was the latency of the P1 cortical auditory evoked potential. Because P1 latencies vary as a function of chronological age, they...
Article
The aim of our research was to estimate the time course of development and plasticity of the human central auditory pathways following cochlear implantation. We recorded cortical auditory-evoked potentials in 3-year-old congenitally deaf children after they were fitted with cochlear implants. Immediately after implantation cortical response latenci...
Article
Full-text available
The goal of this study was to determine whether there is a sensitive period during early development when a cochlear implantation can occur into a minimally degenerate and/or highly plastic central auditory system. Our measure of central auditory deprivation was latency of the P1 auditory evoked potential, whose generators include auditory thalamoc...
Article
Full-text available
Auditory evoked potential (AEP) correlates of the neural representation of stimuli along a /ga/-/ka/ and a /ba/-/pa/ continuum were examined to determine whether the voice-onset time (VOT)-related change in the N1 onset response from a single to double-peaked component is a reliable indicator of the perception of voiced and voiceless sounds. Behavi...