PhD position at the Institute of Neuroscience - Identification of VNS response

Vagus nerve stimulation is an add-on treatment for patients with refractory epilepsy. Despite its well-established use in clinical practice, mechanisms of action remain poorly understood and only one third of implanted patients respond to the treatment. This project aims to improve VNS therapy by developing new neurophysiological tools to identify biomarkers of clinical response.

The vagus nerve projects to the nucleus of tractus solitarius, activating in the brainstem the locus coeruleus (LC), the main source of noradrenaline (NE) in the brain, which relays to thalamus, amygdala and hippocampus, and in turn projects to the cortex1,2. Noradrenergic transmission has a key role in antiepileptogenesis3, and preclinical experiments indicate that activation of the LC-NE system is critical to the seizure suppressing effect of VNS4–7. This pathway may provide an explanation to the antidepressant8,9, attentional10, and wakefulness-promoting effects11,12 also reported with VNS. Although a direct measurement of LC activity in VNS-implanted human patients is still lacking, there exists indirect evidence of LC activation. Pupil size and P300 responses to event-related-potentials are commonly used to study the tonic and phasic influences of the LC-NE system on brain excitability13,14 . In addition, EEG studies postulated neural desynchronization as a possible mechanism of VNS action15. Interestingly, LC-derived noradrenaline may have a direct role in modulating EEG synchronization3,7. This project will have as goal to study P300/pupil dilation and EEG synchronisation in VNS patients, to better understand its mechanisms of action and find biomarkers of response.

The PhD research will start 1/10/2024. Funding is available until 1/12/2025, thereafter the candidate will need to apply for FNRS/FRIA funding. The researcher will be based at the UCLouvain, located in Brussels (Belgium). Your promotor will be Pr. Riëm El Tahry, neurologist at Cliniques Universitaires Saint Luc and PI at IONS, UCL, Pole NEUR. Your co-promoter will be Pr. Antoine Nonclercq, PI at BEAMS department, ULB.

We are looking for a highly motivated engineer with specific interest in Neurosciences, prepared to integrate in a multidisciplinary team consisting of neurologists, neurophysiologists and engineers. Fluent English and BASIC FRENCH are required. Matlab knowledge is highly appreciated.

Application: Interested candidates are requested to send their application to Pr. Riëm El Tahry (riem.eltahry@saintluc.uclouvain.be), with  a copy to Pr. Antoine  Nonclercq (anonclerq@ulb.ac.be), including a cover letter describing yourself and your interests, a resume, your ranking and at least 1 recommendation letter.

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