"Re-membering" your life: Motor contributions to episodic autobiographical memory and autonoetic consciousness
Episodic autobiographical memory (EAM) retrieval is often accompanied by autonoetic consciousness (ANC) â the feeling of â re-experiencingâ past events. A large body of work shows that such recollection is supported by cortical reinstatement: the reactivation, at retrieval, of sensoryâ perceptual systems that were engaged at encoding. Yet, most evidence concerns visual and auditory signals, leaving unanswered the question of whether and how the motor system participates in remembering. Across this thesis I asked the following questions: is there such thing as a motor reinstatement? If so, in what form does it manifest? Does it participate to the phenomenology of ANC? I first addressed this question with an fMRI paradigm, which revealed that during free retrieval of previously encoded events associated with motor actions, the motor cortex (primary motor cortex together with higher-order motor areas) reactivates, in a lateralized, effector-specific manner. Activity in higher-order motor regions scaled with trial-wise re-experiencing ratings, and functional connectivity between hippocampus and motor cortices increased during free retrieval, all providing strong evidence for motor reinstatement (Chapter 1, experiment 1). These results were corroborated and extended in two subsequent studies: one showing evidence for motor reinstatement at the peripheral level, through muscle EMG recordings (Chapter 1, experiment 2), and the other revealing lateralized differential mu and beta power during free retrieval (Chapter 3). In an exploratory diffusion MRI study, I then showed, that fractional anisotropy in the uncinate fasciculus could predict individual variability in re-experience vividness (Chapter 3). These results suggest that trait-like differences in ANC phenomenology relies, at least in part, on the integrity of hippocampalâ neocortical bundles. Finally, I introduced a new, continuous, behavioral index of autonoetic consciousness during EAM retrieval: Viewpoint Retrieval Accuracy (VRA). I showed that participantsâ ability to reconstruct their original perspective over an event (VRA) the following day, statistically predicted their re-experiencing ratings for the event (Chapter 4). We propose that VRA could be used as a behavioral proxy for the vividness of ANC during EAM retrieval. Taken together, these findings provide evidence for a re-enacted retrieval, recruiting motor and bodily traces, in addition to exteroceptive traces. This thesis thus advances an embodied view of EAM in which sensorimotor components are part of the memory trace and contribute to ANC phenomenology.
Prof. Alexander Mathis (président) ; Prof. Olaf Blanke, Prof. Dimitri Nestor Alice Van De Ville (directeurs) ; Prof. Friedhelm Hummel, Dr Ulrike Rimmele, Prof. Donna Rose Addis (rapporteurs)
2025
Lausanne
2025-10-24
11307
172