Induced Microgyria and Auditory Temporal Processing in Rats: A Model for Language Impairment?

The ‘rapid temporal processing’ and the ‘temporal sampling framework’ hypotheses have been proposed to account for the deficits in language and literacy development seen in specific language impairment and dyslexia. This paper reviews these hypotheses and concludes that the proposed causal chains between the presumed auditory processing deficits and the observed behavioural manifestation of the disorders are vague and not well established empirically. Several problems and limitations are identified. Most data concern correlations between distantly related tasks, and there is considerable heterogeneity and variability in performance as well as concerns about reliability and validity. Little attention is paid to the distinction between ostensibly perceptual and metalinguistic tasks or between implicit and explicit modes of performance, yet measures are assumed to be pure indicators of underlying processes or representations. The possibility that diagnostic categories do not refer to causally and behaviourally homogeneous groups needs to be taken seriously, taking into account genetic and neurodevelopmental studies to construct multiple-risk models. To make progress in the field, cognitive models of each task must be specified, including performance domains that are predicted to be deficient versus intact, testing multiple indicators of latent constructs and demonstrating construct reliability and validity.

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Auditory Phenotypic Variability in Friedreich’s Ataxia Patients

The Cerebellum ◽

10.1007/s12311-021-01236-9 ◽

2021 ◽

Author(s):

Nehzat Koohi ◽

Gilbert Thomas-Black ◽

Paola Giunti ◽

Doris-Eva Bamiou

Keyword(s):

Speech Perception ◽

Temporal Processing ◽

Friedreich’S Ataxia ◽

Cognitive Status ◽

Friedreich's Ataxia ◽

Spatial Processing ◽

Auditory Temporal Processing ◽

Processing Ability ◽

Brainstem Response ◽

Auditory Impairment

AbstractAuditory neural impairment is a key clinical feature of Friedreich’s Ataxia (FRDA). We aimed to characterize the phenotypical spectrum of the auditory impairment in FRDA in order to facilitate early identification and timely management of auditory impairment in FRDA patients and to explore the relationship between the severity of auditory impairment with genetic variables (the expansion size of GAA trinucleotide repeats, GAA1 and GAA2), when controlled for variables such as disease duration, severity of the disease and cognitive status. Twenty-seven patients with genetically confirmed FRDA underwent baseline audiological assessment (pure-tone audiometry, otoacoustic emissions, auditory brainstem response). Twenty of these patients had additional psychophysical auditory processing evaluation including an auditory temporal processing test (gaps in noise test) and a binaural speech perception test that assesses spatial processing (Listening in Spatialized Noise-Sentences Test). Auditory spatial and auditory temporal processing ability were significantly associated with the repeat length of GAA1. Patients with GAA1 greater than 500 repeats had more severe auditory temporal and spatial processing deficits, leading to poorer speech perception. Furthermore, the spatial processing ability was strongly correlated with the Montreal Cognitive Assessment (MoCA) score. To our knowledge, this is the first study to demonstrate an association between genotype and auditory spatial processing phenotype in patients with FRDA. Auditory temporal processing, neural sound conduction, spatial processing and speech perception were more severely affected in patients with GAA1 greater than 500 repeats. The results of our study may indicate that auditory deprivation plays a role in the development of mild cognitive impairment in FRDA patients.

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Postnatal development of synaptic properties of the GABAergic projection from the inferior colliculus to the auditory thalamus

Journal of Neurophysiology ◽

10.1152/jn.00021.2013 ◽

2013 ◽

Vol 109 (12) ◽

pp. 2866-2882 ◽

Cited By ~ 22

Author(s):

Yamini Venkataraman ◽

Edward L Bartlett

Keyword(s):

Inferior Colliculus ◽

Temporal Processing ◽

Brain Slices ◽

Critical Time ◽

Membrane Properties ◽

Auditory Temporal Processing ◽

Postsynaptic Potentials ◽

Auditory Thalamus ◽

Inhibitory Postsynaptic Potentials ◽

Medial Geniculate

The development of auditory temporal processing is important for processing complex sounds as well as for acquiring reading and language skills. Neuronal properties and sound processing change dramatically in auditory cortex neurons after the onset of hearing. However, the development of the auditory thalamus or medial geniculate body (MGB) has not been well studied over this critical time window. Since synaptic inhibition has been shown to be crucial for auditory temporal processing, this study examined the development of a feedforward, GABAergic connection to the MGB from the inferior colliculus (IC), which is also the source of sensory glutamatergic inputs to the MGB. IC-MGB inhibition was studied using whole cell patch-clamp recordings from rat brain slices in current-clamp and voltage-clamp modes at three age groups: a prehearing group [ postnatal day (P)7–P9], an immediate posthearing group (P15–P17), and a juvenile group (P22–P32) whose neuronal properties are largely mature. Membrane properties matured substantially across the ages studied. GABAA and GABAB inhibitory postsynaptic potentials were present at all ages and were similar in amplitude. Inhibitory postsynaptic potentials became faster to single shocks, showed less depression to train stimuli at 5 and 10 Hz, and were overall more efficacious in controlling excitability with age. Overall, IC-MGB inhibition becomes faster and more precise during a time period of rapid changes across the auditory system due to the codevelopment of membrane properties and synaptic properties.

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Auditory temporal processing of preschool-age children with typical development and phonological disorder

2008 International Conference on Audio, Language and Image Processing ◽

10.1109/icalip.2008.4590178 ◽

2008 ◽

Author(s):

Chang Liu ◽

Alexis Whitesell

Keyword(s):

Temporal Processing ◽

Preschool Age ◽

Typical Development ◽

Auditory Temporal Processing ◽

Preschool Age Children

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The development of auditory temporal processing during the first year of life

10.31234/osf.io/s6b8e ◽

2021 ◽

Author(s):

Laurianne Cabrera ◽

Bonnie K. Lau

Keyword(s):

Temporal Processing ◽

Temporal Structure ◽

Temporal Information ◽

First Year ◽

Auditory Temporal Processing ◽

Speech Stimuli ◽

Temporal Cues ◽

Neurophysiological Studies ◽

Psychophysical Studies ◽

First Year Of Life

The processing of auditory temporal information is important for the extraction of voice pitch, linguistic information, as well as the overall temporal structure of speech. However, many aspects regarding its early development remains not well understood. This paper reviews the development of different aspects of auditory temporal processing during the first year of life when infants are acquiring their native language. First, potential mechanisms of neural immaturity are discussed in the context of neurophysiological studies. Next, what is known about infant auditory capabilities is considered with a focus on psychophysical studies involving non-speech stimuli to investigate the perception of temporal fine structure and envelope cues. This is followed by a review of studies involving speech stimuli, including those that present vocoded signals as a method of degrading the spectro-temporal information available to infant listeners. Finally, we highlight key findings from the cochlear implant literature that illustrate the importance of temporal cues in speech perception.

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