LEADER: Dr Chen Song
WG1 is aimed at developing and improving existing MRI sequences as well as generating novel analysis method and setting up analyses pipelines for other WGs. The output of WG1 should allow neuroarchitectural mapping through biophysical modelling based on a broad range of MRI-based structural and functional brain characteristics. Group members include experts on and developers of quantitative MRI (qMRI) including Diffusional Kurtosis Imaging (DKI) sequences and analysis. qMRI provides quantitative and specific biomarkers of tissue microstructure. Compared to conventional T1-weighted MRI, it is more comparable across time points and imaging sites1 and allows biophysical inferences into mechanisms underlying brain changes. This work will, among other things, use state of the art “quantitative segmentation” techniques that have been designed to identify anatomical sub-structures at an individual level. These include thalamic and brainstem nuclei.
LEADER: Dr Jordi Solé-Casals
WG2 is aimed at developing statistical methods and coordinating/deciding specific analysis procedures within multiple domains. A primary domain is relating behavioural characteristics to neuroarchitectural characteristics. This will be done by use of multivariate analyses (incl. potentially machine learning). For this aspect, a subgroup will be formed that includes two companies specialised in AI and machine learning as well as university statisticians. A secondary domain is models of metacognition, including the signal detection theory (SDT) based models such as meta-d´. A subgroup consisting of statisticians, neuroscientists, and psychologists is formed with this focus. The subgroup includes leading developers of software for calculation of meta-d´. As such, the data from multiple WGs feed into WG2, and the research deliverables of WG2 feed directly into other WGs that in turn use the statistical analysis scripts provided by WG2.
LEADER: Dr Manon Grube
WG3 developing paradigms investigating conscious perception. These paradigms includes classic phenomena such as threshold perception, bistable perception, and visual illusions as well as a series of perceptual acuity tasks functioning as control tasks. The WG is formed by Action Participants who are leading European experts on visual/auditory perception in general, perceptual masking, subthreshold perception, sensory evidence accumulation, the influence of interoception on conscious visual perception, bistable perception (including binocular rivalry and structure-from-motion), and visual illusions (including the influence of surround modulation on illusion size). Many WG Action Participants have substantial neuroimaging experience.
LEADER: Dr Elisa Filevich
WG4 aims to develop paradigms investigating metacognitive judgments of visibility, memory and other conscious contents. These paradigms include visibility judgments, confidence ratings and their variants. The important part of the WG tasks is to decide on the method allowing to dissociate the metacognitive component of the judgment from the content dependent variability (like strength of a stimulus, memory representation, etc) and investigate the relation between metacognition and conscious awareness (especially the question whether metacognition may be unconscious and the challenge of identifying the cognitive and neuronal mechanisms of both metacognition and conscious awareness). We assume that at least a part of the debate on neural correlates of consciousness is based on the discussion on whether subjective reports allows to measure NCCs or rather they contaminate the results of the studies investigating consequences but not mere correlates of consciousness. We believe that this problem could be solved only if the relation between metacognition and awareness will be well defined. The network of Action Participants includes multiple European experts on metacognition who, together, have published several key articles on the topic.
LEADER: Dr Jovana Bjekić
WG5 aims to develop paradigms investigating consciousness in context of learning and memory. These paradigms include implicit learning (e.g. artificial grammar learning, sequence learning) and implicit memory (e.g. word stem completion task) as well as classical explicit learning and memory procedures allowing to study conscious awareness of a memory content. Most of the neuronal theories of consciousness have been proposed in context of the visual perception. We believe that the general neuroarchitectural model of consciousness should refer to other types of conscious content. The network of proposers include multiple experts in the field who, together, have published multiple key articles in recent years.
LEADER: Prof. Melanie Wilke
WG6 aims to dissociate the neural circuits involved in conscious states in brain injury patients as opposed to the focus on conscious contents in healthy normal participants seen in WG3-5. Specifically, WG6 asks which brain structures and which interactions between them are critical for diagnosis and prognosis in disorders of consciousness, and it asks how to dissociate impairment in any of these subfunctions in human patient populations. This entails building MRI based neuroarchitectural models for patients and examining how they differ from those of healthy controls, and how individual patient neuroarchitectural models predict outcome conscious states. The WG will focus on a range of brain damage types that are all associated with disorders of consciousness, e.g. anoxic brain injury.
In order to better discriminate perceptual, metacognitive and motor decision/intention components from overall conscious states, part of the WG will further develop physiological (autonomous) readouts that allow to reliably infer subjects’ conscious perception and decisions without the requirement of behavioral reports (pupil size, heart beat frequency/phase, EEG dynamics, fMRI-EEG markers in selected brain regions). In order to understand changes on neural networks induced by brain damage, part of the experiments concurrently measure neural activity at different temporal and spatial scales, ranging from signals generated by electrical activity of single neurons and their respective populations to activity on larger scales such as fMRI BOLD signals.
WG6 consists of a mix of basic and clinical neuroscientists as well as clinical practitioners with many years of experience. Locally, WG6 works with additional non-proposer clinical collaborators, including researchers and practitioners in neurorehabilitation.
LEADER: Dr Claude Bajada
WG7 is tasked with conducting the experimental work, and it consists of members from other WGs in leading roles as well as a number of student assistants. Data is collected at a number of Action Data Collection Sites (ADCS) ensuring that not every Action Participant needs to have local MRI scanning facilities. Currently, three ADCS are confirmed and fully or almost fully funded (two European and one Japanese). WG7 includes a representative or more from WG1 and receives input for MRI sequence design from this group. It also includes one or more representatives from WGs 3-5 and receives behavioural experimental paradigm scripts for these to be piloted and run at the ADCS. WG7 aims to be highly efficient in data collection and is limited to this role. As part of the efficiency, behavioural testing of multiple participants is conducted in parallel to save experimenter time. A pilot study has assessed the feasibility. In this pilot, a small group of experimenters MRI scanned 25 participants in one week and gathered around 7.5 hours of behavioural data from 25 participants in around 2 weeks.