Functional Brain Networks Underlying Recalling and Imagining Autobiographical Events

Poster Session C - Sunday, April 14, 2024, 5:00 – 7:00 pm EDT, Sheraton Hall ABC

Ava Momeni^1,2 (ava.momeni@ubc.ca), Donna Addis^3,4,5, Eva Feredoes⁶, Florentine Klepel⁷, Maiya Rasheed^1,2, Abhijit Chinchani^1,2, Todd Woodward^1,2; ¹BC Mental Health and Addictions Research Institute, Canada, ²Department of Psychiatry, University of British Columbia, Canada, ³Department of Psychology, University of Toronto, Canada, ⁴Rotman Research Institute, Baycrest Health Sciences, Canada, ⁵School of Psychology, The University of Auckland, New, ⁶School of Psychology and Clinical Language Sciences at the University of Reading, Reading, United Kingdom, ⁷Medical Psychology and Behavioural Neurobiology Institute, Eberhard Karls Universität Tübingen, Germany

Functional magnetic resonance imaging (fMRI) studies typically explore the blood-oxygen-level-dependent (BOLD) signal underlying discrete cognitive processes that occur over milliseconds to a few seconds. However, autobiographical cognition is more protracted and requires fMRI tasks with longer trials to capture the temporal dynamics of the underlying brain networks. In the current study, we provide an updated analysis of the fMRI data obtained from a published autobiographical event simulation task, with a slow-event-related design (34-second trials), that involved participants recalling past events, imagining past/future events, and completing a semantic association control task. Our updated analysis using Constrained Principal Component Analysis for MRI (fMRI-CPCA) lengthened the temporal window, kept network-level anatomical depictions constant over time points to extract networks stable over time, and enabled more networks to be extracted. Results replicated two networks evident in the original results, including the Default Mode Network (DMN) which was activated by the autobiographical event tasks but deactivated by the control task, and the Multiple Demand Network (MDN) which peaked early during all conditions but was more sustained for the Recall task. Two novel networks emerged, including the Access to Internally Stored Information network (AISI) which, while active for all conditions, was more strongly engaged during the imagination and semantic association conditions than during recall, suggesting a role in constructing novel associations. These results indicate that the DMN does not support autobiographical simulation alone but co-activates with the MDN and AISI network depending on evolving task demands during the simulation process.

Topic Area: METHODS: Neuroimaging