Syncopation and the Score

The first and second authors were supported by an EPSRC DTA (www.epsrc.ac.uk) studentship

Language development after cochlear implantation: an epigenetic model

Growing evidence supports the notion that dynamic gene expression, subject to epigenetic control, organizes multiple influences to enable a child to learn to listen and to talk. Here, we review neurobiological and genetic influences on spoken language development in the context of results of a longitudinal trial of cochlear implantation of young children with severe to profound sensorineural hearing loss in the Childhood Development after Cochlear Implantation study. We specifically examine the results of cochlear implantation in participants who were congenitally deaf (N = 116). Prior to intervention, these participants were subject to naturally imposed constraints in sensory (acoustic–phonologic) inputs during critical phases of development when spoken language skills are typically achieved rapidly. Their candidacy for a cochlear implant was prompted by delays (n = 20) or an essential absence of spoken language acquisition (n = 96). Observations thus present an opportunity to evaluate the impact of factors that influence the emergence of spoken language, particularly in the context of hearing restoration in sensitive periods for language acquisition. Outcomes demonstrate considerable variation in spoken language learning, although significant advantages exist for the congenitally deaf children implanted prior to 18 months of age. While age at implantation carries high predictive value in forecasting performance on measures of spoken language, several factors show significant association, particularly those related to parent–child interactions. Importantly, the significance of environmental variables in their predictive value for language development varies with age at implantation. These observations are considered in the context of an epigenetic model in which dynamic genomic expression can modulate aspects of auditory learning, offering insights into factors that can influence a child’s acquisition of spoken language after cochlear implantation. Increased understanding of these interactions could lead to targeted interventions that interact with the epigenome to influence language outcomes with intervention, particularly in periods in which development is subject to time-sensitive experience

Adaptation to sensory loss : Adaptation to sensory loss

The human brain has the remarkable ability to adapt to changes in its environment by benefiting from its ‘plastic’ properties. Following brain injury, the amputation of a limb, or the loss of a sensory input such as peripheral blindness, brain circuitry often seems to be able to reorganize itself in order to compensate for the handicap by being recruited to carry out tasks not associated with their prior ‘default’ functioning. The purpose of this review is to illustrate the brain’s remarkable ability to adapt to changes in its environment, particularly when it is faced with a sensory loss. Two excellent models to study this phenomenon are provided by blind and deaf individuals. In both cases, studies have shown that they appear to compensate for the loss of sensory input with enhanced abilities in their remaining senses. These behavioral modifications are often coupled with changes in cerebral processing, generally in the form of crossmodal recruitment of deaffarented primary and secondary sensory areas. We will also discuss the possible mechanisms underlying these changes and whether the functional topography of these regions present in unimpaired individuals is preserved in blindness and deafness. The notion of a critical period for plastic changes will also be discussed and its importance will be shown to be twofold. On the one hand, the functional relevance of crossmodal processing appears to decrease as a function of the age of onset of the deficiency. On the other hand, the more cortical reorganization takes place, the less likely brain areas will be able to process input from its original sensory modality. This is especially important for deaf individuals as auditory input can now be restored thanks to cochlear implants

Internet video telephony allows speech reading by deaf individuals and improves speech perception by cochlear implant users

OBJECTIVE To analyze speech reading through Internet video calls by profoundly hearing-impaired individuals and cochlear implant (CI) users. METHODS Speech reading skills of 14 deaf adults and 21 CI users were assessed using the Hochmair Schulz Moser (HSM) sentence test. We presented video simulations using different video resolutions (1280 × 720, 640 × 480, 320 × 240, 160 × 120 px), frame rates (30, 20, 10, 7, 5 frames per second (fps)), speech velocities (three different speakers), webcameras (Logitech Pro9000, C600 and C500) and image/sound delays (0-500 ms). All video simulations were presented with and without sound and in two screen sizes. Additionally, scores for live Skype™ video connection and live face-to-face communication were assessed. RESULTS Higher frame rate (>7 fps), higher camera resolution (>640 × 480 px) and shorter picture/sound delay (<100 ms) were associated with increased speech perception scores. Scores were strongly dependent on the speaker but were not influenced by physical properties of the camera optics or the full screen mode. There is a significant median gain of +8.5%pts (p = 0.009) in speech perception for all 21 CI-users if visual cues are additionally shown. CI users with poor open set speech perception scores (n = 11) showed the greatest benefit under combined audio-visual presentation (median speech perception +11.8%pts, p = 0.032). CONCLUSION Webcameras have the potential to improve telecommunication of hearing-impaired individuals