Garreth Prendergast

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BACKGROUND Behavioural studies have highlighted irregularities in recognition of facial affect in children and young people with autism spectrum disorders (ASDs). Recent findings from studies utilising electroencephalography (EEG) and magnetoencephalography (MEG) have identified abnormal activation and irregular maintenance of gamma (>30 Hz) range(More)
Dramatic results from recent animal experiments show that noise exposure can cause a selective loss of high-threshold auditory nerve fibers without affecting absolute sensitivity permanently. This cochlear neuropathy has been described as hidden hearing loss, as it is not thought to be detectable using standard measures of audiometric threshold. It is(More)
In rodents, exposure to high-level noise can destroy synapses between inner hair cells and auditory nerve fibers, without causing hair cell loss or permanent threshold elevation. Such "cochlear synaptopathy" is associated with amplitude reductions in wave I of the auditory brainstem response (ABR) at moderate-to-high sound levels. Similar ABR results have(More)
The temporal envelope of speech is important for speech intelligibility. Entrainment of cortical oscillations to the speech temporal envelope is a putative mechanism underlying speech intelligibility. Here we used magnetoencephalography (MEG) to test the hypothesis that phase-locking to the speech temporal envelope is enhanced for intelligible compared with(More)
Noise-induced cochlear synaptopathy has been demonstrated in numerous rodent studies. In these animal models, the disorder is characterized by a reduction in amplitude of wave I of the auditory brainstem response (ABR) to high-level stimuli, whereas the response at threshold is unaffected. The aim of the present study was to determine if this disorder is(More)
The aim of this study was to investigate the mechanisms involved in the perception of perceptually salient frequency modulation (FM) using auditory steady-state responses (ASSRs) measured with magnetoencephalography (MEG). Previous MEG studies using frequency-modulated amplitude modulation as stimuli (Luo et al., 2006, 2007) suggested that a phase(More)
Magnetoencephalography (MEG) beamformer analyses use spatial filters to estimate neuronal activity underlying the magnetic fields measured by the MEG sensors. MEG "virtual electrodes" are the outputs of beamformer spatial filters. The present study aimed to test the hypothesis that MEG virtual electrodes can replicate the findings from intracortical "depth"(More)
Cochlear synaptopathy (or hidden hearing loss), due to noise exposure or aging, has been demonstrated in animal models using histological techniques. However, diagnosis of the condition in individual humans is problematic because of (a) test reliability and (b) lack of a gold standard validation measure. Wave I of the transient-evoked auditory brainstem(More)
In this study we investigate whether stimulus variability affects the auditory steady-state response (ASSR). We present cosinusoidal AM pulses as stimuli where we are able to manipulate waveform shape independently of the fixed repetition rate of 4 Hz. We either present sounds in which the waveform shape, the pulse-width, is fixed throughout the(More)
Many experimental studies into human brain function now use magnetoencephalography (MEG) to non-invasively investigate human neuronal activity. A number of different analysis techniques use the observed magnetic fields outside of the head to estimate the location and strength of the underlying neural generators. One such technique, a spatial filtering(More)