Article

Listening difficulties in children: Bottom-up and top-down contributions

MRC Institute of Hearing Research, Nottingham NG7 2RD, UK. Electronic address: .
Journal of Communication Disorders (Impact Factor: 1.52). 06/2012; 45(6):411-8. DOI: 10.1016/j.jcomdis.2012.06.006
Source: PubMed

ABSTRACT The brain mechanisms of hearing include large regions of the anterior temporal, prefrontal, and inferior parietal cortex, and an extensive network of descending connections between the cortex and sub-cortical components of what is presently known as the auditory system. One important function of these additional ('top-down') mechanisms for hearing is to modulate the ascending, sensory ('bottom-up') auditory information from the ear. In children, normal, immature hearing during the first decade of life is more strongly influenced by top-down mechanisms than in adulthood. In some children, impaired top-down function presents a significant challenge to their auditory perception, often associated with a range of language and learning difficulties and sometimes called auditory processing disorder. Learning outcomes: Readers will be able to (a) discuss the difference between and integration of auditory information in the ascending, descending, and cortical auditory centres, (b) state alternate interpretations of normal maturation of human hearing in typical children, (c) explain how sensory and cognitive contributions to auditory temporal and spectral processing may be teased apart, (d) discuss how listening difficulties may be assessed in children, and (e) critically assess whether APD is really an auditory problem or may be symptomatic of a broader neurodevelopmental disorder.

4 Followers
 · 
130 Views
  • Source
    • "While the ascending, sensory system is largely mature by 2 years of age (Moore, 2002), more central and cognitive functions continue to develop into adolescence and even adulthood (e.g., Bishop et al., 2011; Moore and Linthicum, 2007). It is likely therefore that cognitive limitations will play a greater role than sensory limitations in children's difficulties in performing perceptual tasks (see Moore, 2012). Indeed, Halliday et al. (2008) provided evidence in support of this suggestion by training 6-11 year old children on a frequency discrimination task with a fixed standard frequency. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Internal noise is ubiquitous to information processing systems in the brain. It can originate in low-level, sensory systems (e.g., stochastic neural firing) or high-level cognitive functions (e.g., fluctuations in attention). Added to inefficiencies associated with the decision making process, it compromises our ability to make perceptual judgements even under ideal conditions (i.e., in the absence of external noise). We present evidence herein that performance-limiting internal noise and inefficiency of various origins can be reduced through training, resulting in improved behavioural performance. We promote the view that reducing or even removing these limiting processes is what defines perceptual learning, and that transfer of learning to untrained tasks critically depends on those tasks having a limiting process in common with the trained task. We present implications of this view for our understanding of perceptual learning during development and in atypical populations, as well as to the more practical aspects of designing perceptual and cognitive training programmes that will demonstrate benefits beyond the training tasks themselves.
    4th International Symposium on Auditory and Audiological Research, Nyborg, Denmark; 08/2013
  • [Show abstract] [Hide abstract]
    ABSTRACT: Auditory processing disorder (APD) describes a mixed and poorly understood listening problem characterised by poor speech perception, especially in challenging environments. APD may include an inherited component, and this may be major, but studies reviewed here of children with long-term otitis media with effusion (OME) provide strong evidence for changes in auditory processing acquired through altered experience (deprivation) and brain plasticity. Whether inherited or acquired, it is suggested that APD may be reversed by active learning. Training tunes both bottom-up and top-down neural mechanisms, some that are specific to the trained stimulus and some that reflect more generalised arousal. APD and its treatment therefore provide examples of brain plasticity working either in a negative or in a positive way to modulate listening. LEARNING OUTCOMES: (1) Readers will be able to discuss APD in the context of inheritance and experience. (2) Readers will be able to explain how OME has been shown to alter auditory processing. (3) Readers will be able to list examples of good and bad brain plasticity. (4) Readers will be able to explain what auditory learning is, list some of its properties, and provide examples of its application in therapy for communication disorders.
    Journal of Communication Disorders 07/2007; 40(4):295-304. DOI:10.1016/j.jcomdis.2007.03.005 · 1.52 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Children with listening difficulties, but normal audiometry, may be diagnosed with APD. The diagnosis is typically based on poor performance on tests of perception of both non-speech and speech stimuli. However, non-speech test results correlate only weakly with evaluations of speech-in-noise processing, cognitive skills, and caregiver evaluations of listening ability. The interpretation of speech test results is confounded by the involvement of language processing mechanisms. Overall, listening ability is associated more with higher-level, cognitive and analytic processing than with lower-level sensory processing. Current diagnosis of a child with APD, rather than another problem (e.g. language impairment, LI), is determined more by the referral route than by the symptoms. Co-occurrence with other learning problems suggests that APD may be a symptom of a more varied neurodevelopmental disorder. Alternately, APD has been proposed as a cause of language-based disorders, but there is no one-to-one mapping between listening and language among individuals. Screening for APD may be most appropriately based on a well-validated, caregiver questionnaire that captures the fundamental problem of listening difficulties and identifies areas for further assessment and management. This approach has proved successful for LI, and may in future serve as a metric to help assess other, objective testing methods. Foreword Auditory processing disorder (APD) has a long (> 30 years) and controversial history. The controversies concern absolutely fundamental issues: the definition of APD, its neural basis, test validity and standardization, differentiation from other disorders, and even whether it exists as an independent disorder ( Jerger, 2009 ). To evaluate and interpret the scientific evidence on APD, and to advise the audiology profession, the British Society of Audiology (BSA) established a Special Interest Group (BSA SIG) on APD in 2003. That group has recently published two key documents, a 'Position Statement' and a 'Management Overview' ( BSA, 2011, a , b . See www.thebsa.org.uk 'Procedures and Publications'). In formulating the new position statement, it became clear to the group that several significant differences were developing between their interpretation of the evidence concerning APD and that of the American Academy of Audiology (AAA) , as stated in their recently published 'Guidelines for the diagnosis, treatment and management of children and adults with central auditory processing disorder' ( AAA, 2010 ). To address these differences, and borrowing from British Parliamentary procedure, the BSA SIG decided to develop a 'white paper', a discussion document that could then receive an international set of commentaries from other research groups working on APD. An approach was made to the editor of the International Journal of Audiology who agreed to this suggestion. This paper, and the associated commentaries that follow, are the result.
    International journal of audiology 10/2012; 52. DOI:10.3109/14992027.2012.723143 · 1.43 Impact Factor