UMMs · Unifying Monitoring Models of Verbal Monitoring.

Everyone makes mistakes during speech production. However, to facilitate communication, it is important to limit errors during production (e.g. selecting the wrong word but also disfluencies such as ‘ums’ and stuttering), and to identify errors while listening. This is achieved by applying monitoring mechanisms. Deficits in verbal monitoring mechanisms are linked to severe pathologies, such as stuttering, aphasia and hearing voices. Currently, there are a number of theories that explain part of the mechanisms of verbal monitoring. Despite its central role in language processing, astonishingly, no full account exists. Contemporary verbal monitoring models differ widely with respect to some fundamental properties, indicating significant knowledge gaps. This research project fills in these theoretical gaps by relating the functional brain connectome and structural brain connectome with behavioural measures. We exploit the individual variability of a large cohort of healthy adult individuals, by testing groups on the two extremes of performance on cognitive control tasks, and on two extremes of language production tasks. In four work packages, we investigate the neurobiological and behavioural underpinnings of verbal monitoring in healthy adults. The proposal clarifies 1) if a relationship exists between production competence and monitoring (as per production models of monitoring) and 2) if measures of cognitive control are related to verbal monitoring skills (as per conflict models of monitoring) and 3) the involvement of these processes verbal monitoring in perception. To reach this goal we relate the functional brain connectome and structural brain connectome with behavioural measures. The output of 1-3 is used to inform a new model of verbal monitoring. As a final step, the new model is validated by applying TMS to critical cortical components of the model. The proposed project will constitute major progress in our understanding of the verbal monitoring mechanism.