{"success":true,"database":"eegdash","data":{"_id":"6953f4249276ef1ee07a33fb","dataset_id":"ds005523","associated_paper_doi":null,"authors":["Haydn G. Herrema","Michael J. Kahana"],"bids_version":"1.7.0","contact_info":["Haydn Herrema"],"contributing_labs":null,"data_processed":false,"dataset_doi":"doi:10.18112/openneuro.ds005523.v1.0.1","datatypes":["ieeg"],"demographics":{"subjects_count":21,"ages":[20,36,54,57,34,48,32,36,24,48,23,19,31,47,28,20,34,36,21,34,26,24],"age_min":19,"age_max":57,"age_mean":33.27272727272727,"species":null,"sex_distribution":{"f":12,"m":10},"handedness_distribution":{"r":16,"l":4,"a":2}},"experimental_modalities":null,"external_links":{"source_url":"https://openneuro.org/datasets/ds005523","osf_url":null,"github_url":null,"paper_url":null},"funding":["DARPA RAM: N66001-14-2-4032"],"ingestion_fingerprint":"4f0017b621785b1bfe1203e1aad436bf40a15a32188b612baf44e049f8c9135e","license":"CC0","n_contributing_labs":null,"name":"Spatial Memory of Object Locations with Open-Loop Stimulation at Encoding","readme":"### Spatial Navigation Memory of Object Locations with Open-Loop Stimulation at Encoding\n#### Description\nThis dataset contains behavioral events and intracranial electrophysiological recordings from a spatial navigation memory task with open-loop stimulation at encoding.  The experiment consists of participants encoding object locations during a guided navigation learning phase and then recalling the object locations during a self-navigation test phase.  The data was collected at clinical sites across the country as part of a collaboration with the Computational Memory Lab at the University of Pennsylvania.  This dataset is an open-loop stimulation version of the [YC1](https://openneuro.org/datasets/ds005522) dataset.\nEach session contains 50 trials (2 practice and 48 experimental), and each overall \"trial\" contains 2 learning trials followed by 1 test trial with the same object at the same location.  For learning trial 1, participants are placed at a random location at a given radius from the object.  They are smoothly turned to face the object (1 s), automatically driven to the object location (3 s), and then paused at the object (1 s).  5 seconds later, participants are placed at a new random location and the process repeats for learning trial 2.  On test trials, participants are placed at a random location and orientation, with the object invisible.  They navigate to where they believe the object was located and press a button to record their response.  The environment for all sessions and trials is 64.8 x 36, with coordinates: x = (-32.4, 32.4), y = (-18.0, 18.0).\nThis study contains open-loop electrical stimulation of the brain during encoding.  There is no stimulation during the retrieval phase.  Stimulation is delivered to a single electrode at a time, with locations chosen in the hippocampus and entorhinal cortex.  Stimulation parameters are included in the behavioral events tsv files, denoting the anode/cathode labels, amplitude, pulse frequency, pulse width, and pulse count.\nHalf of the (experimental) trials are assigned to the stimulation condition, and stimulation and no stimulation trials are alternated.  On stimulation trials, stimulation occurs during both of the associated learning trials.  Stimulation begins at the onset of turning towards the object's location and lasts for the 5 seconds of the learning trial (1s turn + 3s drive + 1s pause).\nThe trials are blocked by a counterbalanced scheme, so for every stimulated trial there is another non-stimulated trial with reflected object position, starting position, and orientation.  This counterbalancing ensures stimulated and non-stimulated trials are difficulty matched.  Each block contains 2 trials (i.e., 2 x (2 learning, 1 test)), with object (X, Y) and starting locations (x, y).  Bold represents stimulation:\n- **(X1, Y1)**\n    - **(x1', y1')**\n    - **(x1'', y1'')**\n    - (x1''', y1''')\n- (X2, Y2)\n    - (x2', y2')\n    - (x2'', y2'')\n    - (x2''', y2''')\nThe paired block contains 2 trials in the opposite order with object and starting locations:\n- **(-X2, -Y2)**\n    - **(-x2', -y2')**\n    - **(-x2'', -y2'')**\n    - (-x2''', -y2''')\n- (-X1, -Y1)\n    - (-x1', -y1')\n    - (-x1'', -y1'')\n    - (-x1''', -y1''')\n#### To Note\n* The iEEG recordings are labeled either \"monopolar\" or \"bipolar.\"  The monopolar recordings are referenced (typically a mastoid reference), but should always be re-referenced before analysis.  The bipolar recordings are referenced according to a paired scheme indicated by the accompanying bipolar channels tables.\n* Each subject has a unique montage of electrode locations.  MNI and Talairach coordinates are provided when available.\n* Recordings done with the Blackrock system are in units of 250 nV, while recordings done with the Medtronic system are estimated through testing to have units of 0.1 uV.  We have completed the scaling to provide values in V.\n#### Contact\nFor questions or inquiries, please contact sas-kahana-sysadmin@sas.upenn.edu.","recording_modality":["ieeg"],"senior_author":"Michael J. Kahana","sessions":["0","1","2","3","4","5","6"],"size_bytes":74834541025,"source":"openneuro","study_design":null,"study_domain":null,"tasks":["YC2"],"timestamps":{"digested_at":"2026-04-22T12:28:33.949073+00:00","dataset_created_at":"2024-09-24T16:57:08.474Z","dataset_modified_at":"2024-09-24T18:53:29.000Z"},"total_files":102,"storage":{"backend":"s3","base":"s3://openneuro.org/ds005523","raw_key":"dataset_description.json","dep_keys":["CHANGES","README","participants.json","participants.tsv"]},"tagger_meta":{"config_hash":"4a051be509a0e3d0","metadata_hash":"30254d885f22d2d7","model":"openai/gpt-5.2","tagged_at":"2026-01-20T18:26:16.884754+00:00"},"tags":{"pathology":["Surgery"],"modality":["Visual"],"type":["Memory"],"confidence":{"pathology":0.6,"modality":0.7,"type":0.9},"reasoning":{"few_shot_analysis":"Closest few-shot by cognitive construct is the digit-span dataset (Healthy/Auditory/Memory), which labels an explicit encode/maintain/recall paradigm as Type=Memory; this guides mapping the present dataset’s “encoding” and “recall” phases to Type=Memory. For Modality, multiple few-shots label screen-based tasks as Visual (e.g., visual discrimination; motor movement/imagery with on-screen targets), which matches the present dataset’s virtual spatial navigation environment and object-location cues. For Pathology, the intraoperative stimulation example labeled Pathology=Surgery (with non-healthy clinical recording context); this guides treating intracranial clinical recordings with stimulation as likely involving a surgical/implant clinical context even when the specific diagnosis is not stated.","metadata_analysis":"Key task/cognitive facts:\n- Memory focus is explicit: \"spatial navigation memory task\" and \"participants encoding object locations\" and \"then recalling the object locations\".\n- Task structure reinforces episodic/spatial memory: \"2 learning trials followed by 1 test trial with the same object at the same location\" and \"They navigate to where they believe the object was located\".\nKey clinical/recording context:\n- Intracranial + clinical context: \"behavioral events and intracranial electrophysiological recordings\" and \"data was collected at clinical sites\".\n- Intervention/stimulation present: \"open-loop electrical stimulation of the brain during encoding\" with stimulation in \"hippocampus and entorhinal cortex\".\nKey modality cues (implicit visual/VR navigation): \"guided navigation\", \"environment ... with coordinates\", and \"object invisible\" on test trials, consistent with a visually presented virtual environment.","paper_abstract_analysis":"No useful paper information.","evidence_alignment_check":"Pathology:\n1) Metadata says: \"intracranial electrophysiological recordings\" and \"data was collected at clinical sites\" (implies clinical implant/surgical setting but does NOT name a diagnosis).\n2) Few-shot suggests: intracranial/intraoperative stimulation contexts are labeled as Surgery in the provided conventions.\n3) Alignment: partial (both indicate a clinical/surgical context), but diagnosis is unstated.\n4) Resolution: choose Surgery as the best fit to the clinical intracranial/stimulation setting, with reduced confidence due to lack of explicit diagnosis.\n\nModality:\n1) Metadata says: \"spatial navigation\" in a defined \"environment\" with object visibility manipulation (\"object invisible\" during test), implying a visually guided virtual-navigation task.\n2) Few-shot suggests: screen/visual discrimination/target paradigms map to Visual modality.\n3) Alignment: aligned (virtual navigation/object cues are predominantly visual).\n\nType:\n1) Metadata says: \"Spatial Navigation Memory of Object Locations\"; \"encoding object locations\"; \"recalling the object locations\".\n2) Few-shot suggests: explicit encoding/recall tasks map to Memory (e.g., digit span labeled Memory).\n3) Alignment: strongly aligned.","decision_summary":"Top-2 candidates with head-to-head comparison:\n\nPathology:\n- Surgery: Supported by \"intracranial electrophysiological recordings\", \"clinical sites\", and direct brain stimulation during the experiment (implant context likely). Few-shot intraoperative/stimulation conventions support Surgery for clinical recording contexts.\n- Unknown: Also plausible because no explicit recruitment diagnosis (e.g., epilepsy) is stated anywhere in the provided metadata.\nWinner: Surgery (clinical intracranial implant context is explicit, but diagnosis is not).\nConfidence basis: inference from 2 clinical-context quotes without explicit diagnosis → moderate.\n\nModality:\n- Visual: Implied by virtual spatial navigation in an \"environment\" and visibility manipulation (\"object invisible\"), typical of visually presented navigation tasks.\n- Motor: Participants \"press a button\" and navigate, but response modality is not the stimulus modality; stimuli are environmental/object-location cues.\nWinner: Visual.\nConfidence basis: strong contextual inference but no explicit 'visual stimuli' phrase.\n\nType:\n- Memory: Explicit \"encoding\" and \"recalling\" of object locations; test requires returning to remembered location.\n- Clinical/Intervention: Brain stimulation is present, but the primary construct described is memory performance during encoding/retrieval rather than a clinical treatment study.\nWinner: Memory.\nConfidence basis: 3+ explicit memory-related phrases (title line + encoding + recall + test trial description)."}},"nemar_citation_count":0,"computed_title":"Spatial Memory of Object Locations with Open-Loop Stimulation at Encoding","nchans_counts":[{"val":144,"count":7},{"val":166,"count":7},{"val":182,"count":7},{"val":180,"count":7},{"val":126,"count":6},{"val":50,"count":5},{"val":56,"count":5},{"val":156,"count":5},{"val":109,"count":4},{"val":141,"count":4},{"val":118,"count":4},{"val":133,"count":3},{"val":68,"count":3},{"val":64,"count":3},{"val":123,"count":2},{"val":100,"count":2},{"val":85,"count":2},{"val":76,"count":2},{"val":120,"count":2},{"val":108,"count":2},{"val":94,"count":2},{"val":104,"count":2},{"val":138,"count":2},{"val":87,"count":2},{"val":174,"count":2},{"val":110,"count":1},{"val":143,"count":1},{"val":80,"count":1},{"val":112,"count":1},{"val":188,"count":1},{"val":92,"count":1},{"val":173,"count":1},{"val":124,"count":1},{"val":88,"count":1},{"val":163,"count":1}],"sfreq_counts":[{"val":1000.0,"count":58},{"val":1600.0,"count":22},{"val":500.0,"count":18},{"val":499.7071,"count":2},{"val":999.0,"count":2}],"stats_computed_at":"2026-04-22T23:16:00.309878+00:00","total_duration_s":303587.6146446049,"author_year":"Herrema2024_Spatial_Memory","canonical_name":null}}