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bioRxiv · 10.1101/2025.06.20.660447

Functional Specialization of Angular Gyrus and Precuneus Subregions for Perspective-Guided Autobiographical Memory Retrieval

Kucuktas, S.·St Jacques, P. L.
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Abstract

Autobiographical memory (AM) retrieval involves goal-directed and reconstructive processes that unfold over time. A key feature of this process is the visual perspective adopted during remembering, which shapes subjective memory experience. Using fMRI, we cued participants to retrieve AMs from an own-eyes, observer, or natural perspective followed by an event probe. Our design temporally isolates preparatory (cue phase) and reconstructive (probe phase) mechanisms to identify the neural signatures of retrieval orientation, the strategic use of cues to optimize retrieval. Whole-brain and ROI analyses revealed that the angular gyrus (AG) and precuneus support perspective-guided retrieval in distinct ways. During the cue phase, PGp showed greater activity for instructed perspectives than natural retrieval, consistent with preparatory perspective selection. During the probe phase, observer-perspective retrieval elicited greater activity in AG and precuneus, supporting sustained perspective maintenance. Brain-behavior models linked PGp and 7P activity to greater vividness and perspective stability, while precuneus (7M) activity was negatively associated with emotional intensity, especially in the observer condition. These findings reveal phase- and subregion-specific contributions of posterior parietal cortex to the subjective qualities of memory. AG subregions support goal-directed perspective selection and implementation, while precuneus subregions flexibly modulate phenomenological features during memory reconstruction.

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Kucuktas, S., St Jacques, P. L.. 2025-06-21. Functional Specialization of Angular Gyrus and Precuneus Subregions for Perspective-Guided Autobiographical Memory Retrieval. https://doi.org/10.1101/2025.06.20.660447

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