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Although the relationship between auditory processing and reading-related skills has been investigated in school-age populations and in prospective studies of infants, understanding of the relationship between these variables in the period immediately preceding formal reading instruction is sparse. In this cross-sectional study, auditory processing, phonological awareness, early literacy skills, and general ability were assessed in a mixed sample of 88 three-to six-year-old children both cross-sectionally and longitudinally. Results from both cross-sectional and longitudinal analyses suggest the importance of early auditory rise time sensitivity in developing phonological awareness skills, especially in the development of rhyme awareness. [ABSTRACT FROM AUTHOR]

Abstract: Sounds, whether speech or non-speech, vary in how rapidly their peak amplitudes are reached. The time taken for sounds to reach their maximum amplitude is known as the rise time and this variable is an important perceptual cue for representation of the sound amplitude envelope. In the experiments described here healthy adult volunteers passively listened to tones varying in rise time. An oddball design was used and both N1 and MMN components were examined. Experiment 1 contrasted tone stimuli of 15 ms vs. 185 ms rise time. The shorter 15 ms rise time stimuli elicited an N1b over central frontal electrodes of significantly greater amplitude than the 185 ms rise time stimuli. MMN was also observable for both the 15 ms and 185 ms rise time tones when the same stimuli served as deviant vs. standard. Experiment 2 explored the possible confound of rise time and overall stimulus intensity change (tones with shorter rise times sound louder). New stimuli were created in which overall stimulus intensity between short and long rise times was perceptually matched. N1b amplitude differences to the contrastive rise times were still observed, suggesting that N1b may reflect an auditory cortex detector mechanism sensitive to changes in rise time, relatively independently of sound intensity changes. These findings are discussed with reference to their implications for speech perception processes. [Copyright &y& Elsevier]

Children with developmental dyslexia appear to be insensitive to basic auditory cues to speech rhythm and stress. For example, they experience difficulties in processing duration and amplitude envelope onset cues. Here we explored the sensitivity of adults with developmental dyslexia to the same cues. In addition, relations with expressive and receptive rhythm tasks, such as tempi recognition and manual tapping to a metronome, were explored. Our goal was to investigate whether the auditory deficits seen in dyslexia are specific to cues to speech rhythm and stress, or are part of a wider rhythmic awareness problem. A group of 19 undergraduate students with dyslexia were compared with 20 age- and ability-matched controls. The findings confirmed a relationship between auditory rhythm sensitivity and literacy in adults, as well as showing an association with metronome inter-tap-interval variability. [ABSTRACT FROM AUTHOR]

Abstract: It has been hypothesised that auditory processing may be enhanced in autism spectrum disorders (ASD). We tested auditory discrimination ability in 72 adolescents with ASD (39 childhood autism; 33 other ASD) and 57 IQ and age-matched controls, assessing their capacity for successful discrimination of the frequency, intensity and duration differences in pairs of sounds. At the group level, auditory discrimination ability did not differ between the adolescents with and without ASD. However, we found a subgroup of 20% of individuals in the ASD group who showed ‘exceptional’ frequency discrimination skills (defined as 1.65 SDs above the control mean) and who were characterised by average intellectual ability and delayed language onset. Auditory sensory behaviours (i.e. behaviours in response to auditory sensory input) are common in ASD and we hypothesised that these would relate to auditory discrimination ability. For the ASD group, poor performers on the intensity discrimination task reported more auditory sensory behaviours associated with coping with loudness levels. Conversely, those who performed well on the duration discrimination task reported more auditory sensory behaviours across the full range measured. Frequency discrimination ability did not associate with auditory sensory behaviours. We therefore conclude that (i) enhanced frequency discrimination is present in around 1 in 5 individuals with ASD and may represent a specific phenotype; and (ii) individual differences in auditory discrimination ability in ASD may influence the expression of auditory sensory behaviours by modulating the degree to which sounds are detected or missed in the environment. [Copyright &y& Elsevier]