Over the past ~14 years, our research has been focussed on using non-invasive neuro-recording techniques to unravel central auditory processing mechanisms in humans. We use EEG and fMRI to investigate how basic auditory features, such as frequency, pitch and location, are represented in subcortical and cortical auditory structures, and how these representations change in hearing loss. A particular interest in on modulatory mechanisms, including lateral inhibition, efferent control and adaptation. In our past research, we have used adaptation as a tool for probing auditory neuronal tuning properties.
- We have used high-resolution fMRI and micro-structural MRI at 3 and 7T to reveal the organization of early auditory cortex in normal-hearing humans (Besle et al., 2019; Schonwiesner et al., 2015; Langers et al., 2014a, b)
- We have used EEG adaptation to demonstrate that auditory selective attention involves neuronal gain and neuronal sharpening (de Boer & Krumbholz, 2018)
- We have used EEG to demonstrate that the auditory brainstem response to speech (speech ABR) is strongly affected by its cochlear place of origin (Nutall et al., 2015)
- We have used psychoacoustics to measure the effect of the olivo-cochlear efferent system on active cochlear gain (Fletcher et al., 2013, 2015, 2016)
- We have used EEG to investigate the mechanisms of auditory adaptation (Briley & Krumbholz, 2013; Lanting et al. 2013)
- We have used cortical auditory-evoked potentials and fields to reveal cortical representation mechanisms of musical pitch (Briley et al., 2013; Lutkenhoner et al., 2011; Seither-Preisler et al., 2006a, b), sound location and motion (Edmonds & Krumbholz, 2014; Magezi & Krumbholz, 2010; Krumbholz et al., 2007), and phonemic information (Edmonds et al., 2010; Hewson-Stoate et al., 2006)
Our current research aims to apply non-invasive methods to investigate changes in central auditory processing that may arise in consequence of peripheral hearing damage, such as sensorineural hearing loss and auditory deafferentation. Central auditory processing changes may underlie some of the most debilitating impairments associated with such damage - tinnitus, hyperacusis and speech-in-noise difficulty, which are still poorly understood, and not efficiently addressed by current treatments. Our current research projects aim to develop methodology for measuring hearing loss-related neuronal hyper-excitability and cortical tonotopic reorganization, both of which have been suggested as possible causes of tinnitus.