Parallel hippocampal-parietal circuits for self- and goal-oriented processing

Abstract

The hippocampus is critically important for a diverse range of cognitive processes, such as episodic memory, prospective memory, affective processing, and spatial navigation. Using individual-specific precision functional mapping of resting-state functional MRI data, we found the anterior hippocampus (head and body) to be preferentially functionally connected to the default mode network (DMN), as expected. The hippocampal tail, however, was strongly preferentially functionally connected to the parietal memory network (PMN), which supports goal-oriented cognition and stimulus recognition. This anterior–posterior dichotomy of resting-state functional connectivity was well-matched by differences in task deactivations and anatomical segmentations of the hippocampus. Task deactivations were localized to the hippocampal head and body (DMN), relatively sparing the tail (PMN). The functional dichotomization of the hippocampus into anterior DMN-connected and posterior PMN-connected parcels suggests parallel but distinct circuits between the hippocampus and medial parietal cortex for self- versus goal-oriented processing.

Intrinsic functional connectivity in the default mode network predicts mnemonic discrimination: A connectome‐based modeling approach

“…Following this suggestion, one could predict a key role for connectivity between the hippocampus and parietal regions in mnemonic discrimination. Indeed, the prominent structural and functional connectivity between the hippocampus and parietal regions has led some to suggest that there is a "parietal memory network" within the DMN that supports episodic memory (Vincent et al, 2006;Zheng et al, 2021). Although network connections of this kind could potentially enable a recall-to-reject mechanism, the present results showed greater connectivity strength of predictive connections within more anterior than posterior DMN regions.…”

Decision Making as a Learned Skill in Mice and Humans

“…The work discussed earlier in this article shows that the thalamic pathway is involved in generalization and cognitive control of memory and is not unique to self-reflection. While we argue that the posterior pathway has a unique relation to sensory orienting, Zheng et al (2021) do not discuss the special role of the parietal lobe in this function. These differences in pathway function should be fruitful for designing studies to distinguish the differences in the functional roles for the connections between attention and memory.…”

“…This resting state study does not take into account the task-relevant work on modification of the HC by the ACC and the involvement in generalization discussed earlier in this article. While the two pathways shown in Figure 2 and those discussed by Zheng et al (2021) are anatomically similar and are involved in functions related to memory retrieval, the details in their function are somewhat different. The work discussed earlier in this article shows that the thalamic pathway is involved in generalization and cognitive control of memory and is not unique to self-reflection.…”

Hippocampal Metabolic Subregions and Networks: Behavioral, Molecular and Pathological Aging Profiles

“…8A, 8B and 8C). Thus, altogether, the Anterior-subiculum(Red) network appears to corresponds to a "self-oriented" behavioral system [11,35] supporting self, motivation and mentalizing behavior and in uenced by dopaminergic systems.…”

“…This network appears to include the posterior medial subsystem [32], which is particularly engaged in episodic and recollection memory, scene perception, and social cognition including theory of mind. This subsystem seems to belong to a general "goal-oriented" or "word-oriented" behavioural system [11,35], which can be targeted by serotoninergic systems. Thus, the Posterior-Subiculum(Blue), despite being coupled with its anterior counterpart, appears to be part of a larger whole-brain network associated to different behavioral systems and that could be in uenced by different neurotransmitters systems.…”