WIP Special

PrePOSE: Predicting the Pain Outcomes of Surgery for Endometriosis

Presented by Kirralise Hansford

 Abstract: Endometriosis is a chronic gynaecological condition that affects around 10% of women of reproductive age. This condition can cause debilitating pain, infertility, and poor quality of life. Surgery if often offered as a treatment option for patients, especially those with more extensive endometriosis lesions (stages III & IV). Unfortunately, we know that surgery often does not result in a long lasting reduction in pain. Therefore, it is important to try and understand which patients are most likely to benefit from surgery for pain management. Recently, neuropathic and nociplastic mechanisms have been explored in pain maintenance in endometriosis. Historically, only nociceptive mechanisms have been considered, with surgery targeting the peripheral drivers. This study will use fMRI (resting state and noxious punctate stimulation) to determine whether we can predict with pre-surgical measures who will experience a pain reduction following surgery. Analysis will include the use of ROIs from research based on neuropathic-associated regions of interest (notably the pontine reticular formation). Additionally, volumetric and resting state connectivity measures, measures of hypersensitivity, and the use of Quantitative Sensory Testing (QST) and questionnaires will be administered to gain a wider understanding of pain mechanisms and outcomes following surgery for endometriosis.  

 Investigating attention beyond gaze during decision-making using rapid invisible frequency tagging.

Presented by Amy Li

Abstract: Human decision-making studies have suggested that visual attention influences the extent to which evidence is accumulated from choice options, with non-fixated peripheral options being downweighted relative to the fixated option via a fixed parameter. However, this equivalence between gaze and visual attention has been challenged by our recent findings; in a behavioural experiment (N=31), we showed that covert attention to peripheral options is modulated by decision-relevant variables, and has downstream consequences for choice behaviour. The present planned study extends upon this previous behavioural experiment – which could only capture covert attention at a single timepoint during each trial – to investigate how covert attention continuously unfolds throughout the decision process. To provide a continuous index of covert attention, we use rapid invisible frequency-tagging (RIFT) while participants complete a simple value-guided choice task in the MEG scanner. Participants are presented with three patches on each trial; two of these patches are valid choice options and will have different values, and participants choose the higher-valued option to earn a reward. Two of the three patch locations on each trial will be rapidly and imperceptibly flickered, generating RIFT responses in the brain (oscillatory activity in MEG that mimic the stimuli’s flicker frequencies). By examining the time-course of RIFT responses at each of the two tagged frequencies, we will obtain a continuous measure of attentional allocation to patch locations over the time-course of the trial. Analysis will then examine how choice-relevant variables affect covert attentional allocation, and critically, how their contributions vary over the time-course of the decision process.