Self-generation effects: beyond sensory processing
[eng] Our actions shape our everyday experience: what we experience, how we perceive and remember it, is deeply affected by how we interact with the world. Performing an action to deliver a stimulus engages neurophysiological processes which are reflected in the modulation of sensory and pupil respo...
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| Tipo de recurso: | tesis doctoral |
| Estado: | Versión publicada |
| Fecha de publicación: | 2024 |
| País: | España |
| Institución: | Universidad de Barcelona |
| Repositorio: | Dipòsit Digital de la UB |
| OAI Identifier: | oai:diposit.ub.edu:2445/212040 |
| Acceso en línea: | https://hdl.handle.net/2445/212040 http://hdl.handle.net/10803/691125 |
| Access Level: | acceso abierto |
| Palabra clave: | Neurofisiologia Neurociències Psicofisiologia Cervell Neurophysiology Neurosciences Psychophysiology Brain |
| Sumario: | [eng] Our actions shape our everyday experience: what we experience, how we perceive and remember it, is deeply affected by how we interact with the world. Performing an action to deliver a stimulus engages neurophysiological processes which are reflected in the modulation of sensory and pupil responses. Furthermore, research shows that the sensory modulation of those self-generated (SG) stimuli may have an impact on higher order cognitive processes such as memory and personality. The present thesis attempts to elucidate whether actions have an impact on memory encoding and retrieval as well as examining whether the self-generation effects correlate with personality traits. Study I tested whether actions alone are a pivotal part of the production effect, a widely studied phenomenon that shows an increase of memory performance through active learning. Participants (N= 19) listened to sounds presented either during or in between their actions while the event related potentials (ERP) to the sounds were recorded and memory performance was assessed. Results showed attenuation of ERP sensory responses for action-coinciding sounds. However, there was no significant effect on memory performance. Study II went a step further looking into contingent action-sound relationships discerning whether the self-generation of sounds shape memory encoding, parsing the experience by grouping self- and externally generated (EG) stimuli into differentiated events. Participants (N = 25) encoded short sound sequences, in which either the first or last few sounds were SG and the rest EG while ERPs, pupil dilation and memory performance were recorded. Recall of the sequential order of sounds that had originated from within the same event was not higher than from across events, suggesting that the memory representation was not structured by actions. Recall of the sequential order of sounds between EG and SG remained similar, not evidencing a production effect. However, during encoding, we replicated the well-known electrophysiological response attenuation, together with increased pupil dilation for self-generated sounds. Moreover, we found that at the boundary between events, the pupil and electrophysiological responses to the first sound originating from the new source were determined by the direction of the source switch. The results suggest that introducing actions, acts as a stronger contextual shift than removing them, despite not directly contributing to memory performance. Finally, Study III ventured into the realm of individual variability exploring the relationship between personality traits and the self-generation effects. The analysis was performed using data from four experiments (N = 87) from our laboratory, including data from Study II. Electrophysiological measures of self-generation effects on various ERP components, pupil dilation and memory performance, were analyzed along with scores from four personality questionnaires that assessed schizotypal traits and sense of agency. Findings suggest that individuals with higher schizotypal traits exhibit reduced self-generation effects on the Tb ERP component. However, our results challenge previous findings showing a correlation of schizotypal traits with the N1 ERP component. There was no relationship of personality with the pupil response or the memory performance. The findings contribute to our understanding of how interacting with sensory input shapes our experiences, by addressing the unexplored relationships between action effects on sensory responses, pupil dilation and memory. This thesis concludes that: 1) low-level neurophysiological mechanisms tied to action execution do not seem to significantly contribute to the modulation of memory; 2) the introduction of actions appears to exert a more powerful contextual shift compared to removing them; 3) no direct relationship was found between the neuromodulatory mechanisms of action, as reflected by pupil dilation, and the electrophysiological self-generation effects; and 4) individuals with higher schizotypal traits demonstrate reduced self-generation effects in electrophysiological sensory responses; however the N1 may not be the perfect candidate to mirror the underlying prediction deficit. |
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