Positions
Post-doctoral position: Selective Attention: How does Neural Response Modulation in Auditory Cortex Enable Auditory Scene Analysis?
Funding is available from January 2015 for a post-doctoral researcher funded by a grant from the BBSRC. The duration of the grant is 3 years.
We seek a highly motivated individual to persue this exciting project. Applicants should have a PhD (or equivalent) and experience in one or more of the following: psychophysics, in vivo electrophysiology, computational modelling and data analysis including programming in MATLAB.
Project Summary
Our goal is to understand how active listening shapes neural responses in auditory cortex (AC), and to determine whether and when feedback connections from non-primary auditory areas to primary areas facilitate selective attention. Real-world hearing is made challenging by the presence of multiple competing sound sources. Thus, listeners must direct their attention to a source of interest while ignoring others. Recent studies, utilising imaging techniques or ECoG recordings in humans, have demonstrated that neural activity in non-primary AC represents predominantly attended sound sources, yet little is known about the physiological mechanisms that facilitate this.
In this proposal we seek to determine how single cell responses in AC are shaped by current task demands. We will record from the AC of animals actively discriminating speech sounds and trained to report the occurrence of a target word. By employing different variants of the same paradigm we will test how neural responses differ between conditions in which there is only a single stimulus stream, and conditions in which there is a competing stream of masking noise or speech.
We will assess whether changes to single neuron receptive fields are best summarised as gain changes or selectivity changes and determine what stimulus and task attributes determine the neural response. We will test the hypothesis that gain changes are predominantly observed in primary AC and selectivity changes only emerge in higher areas.
Attention related changes in sensory representations are thought to result from feedback connections to AC from other brain regions and within auditory cortex from secondary to primary areas. We will address this hypothesis by determining the behavioural consequences of selectively inactivating these feedback projections during behaviour using spatially and temporally precise optogenetic silencing techniques.
We are always interested to hear from potential PhD students or post-doctoral research fellows. Please Contact Me for details.