Goal-oriented representations in the human hippocampus during planning and navigation

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: May 23, 2023

Abstract Recent work in cognitive and systems neuroscience has suggested that the hippocampus might support planning, imagination, navigation by forming maps capture abstract structure of physical spaces, tasks, situations. Navigation involves disambiguating similar contexts, planning execution a sequence decisions to reach goal. Here, we examine hippocampal activity patterns humans during goal-directed task investigate how contextual goal information are incorporated construction navigational plans. During pattern similarity is enhanced across routes share context navigation, observe prospective activation reflects retrieval related key-decision point. These results suggest that, rather than simply representing overlapping associations or state transitions, shaped goals.

Language: Английский

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Transversal functional connectivity and scene-specific processing in the human entorhinal-hippocampal circuitry

eLife, Journal Year: 2022, Volume and Issue: 11

Published: Oct. 12, 2022

Scene and object information reach the entorhinal-hippocampal circuitry in partly segregated cortical processing streams. Converging evidence suggests that such information-specific streams organize – entorhinal interaction circuitry’s inner communication along transversal axis of hippocampal subiculum CA1. Here, we leveraged ultra-high field functional imaging advance Maass et al., 2015 who report two routes segregating cortex (EC) subiculum. We identify subregions based on preferential connectivity with perirhinal Area 35 36, parahippocampal retrosplenial sources (referred to as EC Area35-based , Area36-based PHC-based RSC-based respectively). Our data show specific scene functionally connected distal Another route, connects a newly identified subiculum/CA1 border, however, shows no selectivity between conditions. results are consistent pathways human circuitry, anatomically organized convergence unique route for information. study thus further characterizes organization this its role memory function.

Language: Английский

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Data-Driven Clustering of Functional Signals Reveals Gradients in Processing Both within the Anterior Hippocampus and across Its Long Axis

Journal of Neuroscience, Journal Year: 2022, Volume and Issue: 42(39), P. 7431 - 7441

Published: Aug. 24, 2022

A particularly elusive puzzle concerning the hippocampus is how structural differences along its long anteroposterior axis might beget meaningful functional differences, in terms of granularity information processing. One measure posits to quantify this by calculating average statistical independence BOLD signal across neighboring voxels, or intervoxel similarity (IVS), and has shown anterior process coarser-grained than posterior hippocampus. This measure, however, yielded opposing results studies developmental healthy aging samples, which also varied fMRI acquisition parameters hippocampal parcellation methods. To reconcile these findings, we measured IVS two separate resting-state acquisitions compared many most widely used methods a large young-adult sample male female humans (Acquisition 1, N = 233; Acquisition 2, 176). Finding conflicting parcellations, reasoned that data-driven approach necessary. end, implemented group masked independent components analysis identify subunits hippocampus, notably separating into anterior-medial, anterior-lateral, posteroanterior-lateral components. Measuring revealed decrease medial-lateral but an increase from posterior. We conclude deeply affected grounding one9s functionally informed allow for more complex reliable characterization SIGNIFICANCE STATEMENT Processing hierarchical scales critical feats cognition considered human. Recently, changes structure, cortical connectivity, apparent properties parcels have been hypothesized underlie gradient show here, choice method itself drastically affects one particular reveals gradients both within nonlinear form axis. These point issue as study reorient interpretation existing results.

Language: Английский

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HippoMaps: Multiscale cartography of the human hippocampal formation

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Feb. 23, 2024

The hippocampus has a unique microarchitecture, is situated at the nexus of multiple macroscale functional networks, contributes to numerous cognitive as well affective processes, and highly susceptible brain pathology across common disorders. These features make model understand how structure covaries with function, in both health disease. Here, we introduce HippoMaps, an open access toolbox online data warehouse for mapping contextualization hippocampal human (http://hippomaps.readthedocs.io). HippoMaps capitalizes on novel unfolding approach shape intrinsic registration capabilities allow cross-subject cross-modal aggregation. We initialize this repository spanning 3D post-mortem histology, ex-vivo 9.4 Tesla MRI, in-vivo structural MRI resting-state (rsfMRI) obtained 3 7 Tesla, together intracranial encephalography (iEEG) recordings epilepsy patients. also contains validated tools spatial map association analysis that correct autocorrelation. All code are compliant community standards, comprehensive tutorials facilitate broad adoption. Applications work span methodologies modalities, scales, clinical basic research contexts, encourage feedback contributions spirit iterative scientific resource development.

Language: Английский

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HippoMaps: Multiscale Cartography of Human Hippocampal Organization

Research Square (Research Square), Journal Year: 2024, Volume and Issue: unknown

Published: March 25, 2024

Abstract The hippocampus has a unique microarchitecture, is situated at the nexus of multiple macroscale functional networks, contributes to numerous cognitive as well affective processes, and highly susceptible brain pathology across common disorders. These features make model understand how structure covaries with function, in both health disease. Here, we introduce HippoMaps, an open access toolbox online data warehouse for mapping contextualization hippocampal human (http://hippomaps.readthedocs.io). HippoMaps capitalizes on novel unfolding approach shape intrinsic registration capabilities allow cross-subject cross-modal aggregation. We initialize this repository spanning 3D post-mortem histology, ex-vivo 9.4 Tesla MRI, in-vivo structural MRI resting-state (rsfMRI) obtained 3 7 Tesla, together intracranial encephalography (iEEG) recordings epilepsy patients. also contains validated tools spatial map association analysis that correct autocorrelation. All code are compliant community standards, comprehensive tutorials facilitate broad adoption. Applications work span methodologies modalities, scales, clinical basic research contexts, encourage feedback contributions spirit iterative scientific resource development.

Language: Английский

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Organization of pRF size along the AP axis of the hippocampus and adjacent medial temporal cortex is related to specialization for scenes versus faces

Cerebral Cortex, Journal Year: 2023, Volume and Issue: 34(1)

Published: Nov. 21, 2023

Abstract The hippocampus is largely recognized for its integral contributions to memory processing. By contrast, role in perceptual processing remains less clear. Hippocampal properties vary along the anterior–posterior (AP) axis. Based on past research suggesting a gradient scale of features processed AP extent hippocampus, representations have been proposed as function granularity this One way quantify such with population receptive field (pRF) size measured during visual processing, which has so far received little attention. In study, we compare pRF sizes within activation images scenes versus faces. We also measure these functional surrounding medial temporal lobe (MTL) structures. Consistent research, find pRFs be larger anterior than posterior hippocampus. Critically, our analysis MTL regions, perirhinal cortex, entorhinal and parahippocampal cortex shows similar correlation between scene sensitivity size. These findings provide conclusive evidence tight relationship image content adjacent cortex.

Language: Английский

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Transcranial magnetic stimulation to the angular gyrus modulates the temporal dynamics of the hippocampus and entorhinal cortex

Cerebral Cortex, Journal Year: 2022, Volume and Issue: 33(6), P. 3255 - 3264

Published: Dec. 27, 2022

Transcranial magnetic stimulation (TMS) delivered to the angular gyrus (AG) affects hippocampal function and associated behaviors (Thakral PP, Madore KP, Kalinowski SE, Schacter DL. Modulation of brain networks produces changes in episodic simulation divergent thinking. 2020a. Proc Natl Acad Sci U S A. 117:12729-12740). Here, we examine if functional resonance imaging (fMRI)-guided TMS disrupts gradient organization temporal signal properties, known as organization, hippocampus (HPC) entorhinal cortex (ERC). For each 2 sessions, was applied either a control site (vertex) or left AG target region (N = 18; 14 females). Behavioral measures were then administered, resting-state scans acquired. Temporal dynamics measured by tracking change fMRI (i) "within" single voxels over time, termed single-voxel autocorrelation (ii) "between" different intervoxel similarity. reduced connectivity with induced more rapid shifting activity between successive time points, lowering autocorrelation, within anteromedial HPC posteromedial ERC. Intervoxel similarity only marginally affected TMS. Our findings suggest that hippocampal-targeted properties along anterior/posterior axis. Further studies should consequences altering these medial areas successful processing information under task demand.

Language: Английский

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Differential involvement of the anterior and posterior hippocampus, parahippocampus, and retrosplenial cortex in making precise judgments of spatial distance and object size for remotely acquired memories of environments and objects

Cerebral Cortex, Journal Year: 2023, Volume and Issue: 33(18), P. 10139 - 10154

Published: July 29, 2023

Abstract The hippocampus is known to support processing of precise spatial information in recently learned environments. It less clear, but crucial for theories systems consolidation, know whether it also supports familiar environments long ago and such precision extends objects numbers. In this fMRI study, we asked participants make progressively more refined distance judgments among well-known Toronto landmarks (whether landmark A closer B or C) examine hippocampal involvement. We tested the was similarly engaged estimating magnitude regarding sizes animals found that only judgment. Activation greater lasted longer posterior than anterior hippocampus, which instead showed modulation as discrimination between distances became fine grained. These findings suggest have different functions are influenced differently by estimation differential distance. Similarly, parahippocampal-place-area retrosplenial cortex were involved condition. By contrast, activation intraparietal sulcus modulated all conditions. Therefore, our study idea related structures implicated retrieving operating even on remote memories whenever required, posted some consolidation.

Language: Английский

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Recall as a Window into Hippocampally Defined Events

Journal of Cognitive Neuroscience, Journal Year: 2024, Volume and Issue: 36(11), P. 2386 - 2400

Published: Jan. 1, 2024

Abstract We experience the present as a continuous stream of information, but often past in parcels unique events or episodes. Decades research have helped to articulate how we perform this event segmentation moment, well and their boundaries influence what later remember. More recently, neuroscientific has suggested that hippocampus plays role at critical moments during formation alongside its established enabling subsequent recall. Here, review explore relationship between processing recall with perspective it can be uniquely characterized by contributions interactions rest brain. Specifically, highlight growing number empirical studies suggesting is important for just ended, bridging gap prior current event, influencing contents trajectories recalled information. also catalogue summarize multifaceted sets findings concerning influenced structure. Lastly, discuss several exciting directions future our understanding might enriched characterizing them terms operations different regions

Language: Английский

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Rapid learning of temporal dependencies at multiple timescales

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 16, 2024

Our environment contains temporal information unfolding simultaneously at multiple timescales. How do we learn and represent these dynamic overlapping streams? We investigated processes in a statistical learning paradigm with simultaneous short long timescale contingencies. Human participants (N=96) played game where they learned to quickly click on target image when it appeared one of 9 locations, 8 different contexts. Across contexts, manipulated the order locations: timescale, pairs sequential locations which appeared; longer set that first vs. second half game. Participants periodically predicted upcoming location, later performed similarity judgements comparing games based their properties. showed context dependent sensitivity both timescales, evidence stronger for modeled using gated recurrent network trained make immediate predictions, demonstrated multilevel timecourses patterns structure mirrored human participants. The model grouped matching rule dissociated low-level more so than high-level information. work shows how humans models can rapidly concurrently acquire

Language: Английский

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