{"success":true,"database":"eegdash","data":{"_id":"6953f4249276ef1ee07a33ec","dataset_id":"ds005489","associated_paper_doi":"10.1038/s41467-017-02753-0","authors":["Haydn G. Herrema","Michael J. Kahana"],"bids_version":"1.7.0","contact_info":null,"contributing_labs":null,"data_processed":false,"dataset_doi":"doi:10.18112/openneuro.ds005489.v1.0.3","datatypes":["ieeg"],"demographics":{"subjects_count":37,"ages":[48,49,39,20,31,47,48,24,32,36,24,48,27,23,40,31,45,49,28,21,20,19,39,34,36,26,40,24,47,30,26,20,29,47,49,41,23,42],"age_min":19,"age_max":49,"age_mean":34.26315789473684,"species":null,"sex_distribution":{"f":23,"m":15},"handedness_distribution":{"r":28,"a":3,"l":7}},"experimental_modalities":null,"external_links":{"paper_url":"https://www.nature.com/articles/s41467-017-02753-0.pdf"},"funding":["DARPA RAM: N66001-14-2-4032"],"ingestion_fingerprint":"b258fc687357cf711579cad40c1cd5ab625584842845cc44323dfde0db5384b7","license":"CC0","n_contributing_labs":null,"name":"Free Recall with Open-Loop Stimulation at Encoding","readme":"### Free Recall with Open-Loop Stimulation at Encoding\n#### Description\nThis dataset contains behavioral events and intracranial electrophysiological recordings from a delayed free recall task with open-loop stimulation at encoding.  The experiment consists of participants studying a list of words, presented visually one at a time, completing simple arithmetic problems that function as a distractor, and then freely recalling the words from the just-presented list in any order.  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 [FR1](https://openneuro.org/datasets/ds004789) dataset.\nThis study contains open-loop electrical stimulation of the brain during encoding.  There is no stimulation during the distractor or retrieval phases.  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.\n20 of the 25 lists in a session are randomly assigned as stimulation lists.  On these lists, stimulation occurs on alternating two-word blocks, meaning 6 of the 12 words are presented with stimulation.  Stimulation starts 200 ms prior to the onset of the first word in the block and lasts for 4.6 seconds, ending 200-450 ms after the offset of the second word (depending on the inter-stimulus interval).  Half of the stimulation lists begin with a stimulation on pair and half begin with a stumulation off pair, but the order of these conditions is random.  A stimulation list that begins with a stimulation on pair would look as follows (with bold indicating stimulation):\n**1 - 2** | 3 - 4 | **5 - 6** | 7 - 8 | **9 - 10** | 11 - 12\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":null,"sessions":["0","1","2","3","4","5","6"],"size_bytes":69730604815,"source":"openneuro","study_design":null,"study_domain":null,"tasks":["FR2"],"timestamps":{"digested_at":"2026-05-31T16:18:59.840037+00:00","dataset_created_at":null,"dataset_modified_at":null},"total_files":154,"storage":{"backend":"s3","base":"s3://openneuro.org/ds005489","raw_key":"dataset_description.json","dep_keys":["CHANGES","README","participants.json","participants.tsv"]},"tagger_meta":{"model":"openai/gpt-4o","tagged_at":"2026-06-10T08:19:41Z","source":"eegdash-llm-tagger"},"tags":{"pathology":["Healthy"],"modality":["Visual"],"type":["Memory"],"confidence":{"pathology":0.9,"modality":0.9,"type":0.9},"reasoning":{"few_shot_analysis":"The dataset involves a free recall task with stimulation during encoding. A similar example in the few-shot is the dataset concerning 'Meta-rdk' with a visual discrimination task, where participants were given a visual task, and decisions about perception were involved. The few-shot provides guidance in identifying visual recall experiments involving memory encodings should be classified under Memory.","metadata_analysis":"Key metadata includes: 'participants studying a list of words, presented visually' and 'intracranial electrophysiological recordings...with open-loop stimulation at encoding.' The task involves studying words visually, a distractor task, and a free recall phase. The dataset description emphasizes a visual task, specifically related to Memory processes.","paper_abstract_analysis":"No useful paper information.","evidence_alignment_check":"Metadata states 'participants studying a list of words, presented visually...and then freely recalling the words,' which aligns with a Memory type classification. Few-shot analogy to a visual memory paradigm underlines similar labeling. Modality aligns as Visual given participants are visually studying words. Pathology aligns with Healthy as there is no clinical diagnosis focus.","decision_summary":"Pathology: Top choice 'Healthy' as there is no clinical population focus. Modality: 'Visual' since the task involves visually presented word lists. Type: 'Memory' because this is a free recall task involving memory encoding and recall. Very consistent evidence aligns metadata and few-shot styles."}},"nemar_citation_count":0,"computed_title":"Free Recall with Open-Loop Stimulation at Encoding","nchans_counts":[{"val":100,"count":12},{"val":64,"count":10},{"val":141,"count":9},{"val":118,"count":8},{"val":96,"count":8},{"val":136,"count":7},{"val":109,"count":7},{"val":72,"count":6},{"val":68,"count":6},{"val":88,"count":6},{"val":70,"count":4},{"val":75,"count":4},{"val":126,"count":4},{"val":87,"count":4},{"val":110,"count":4},{"val":56,"count":4},{"val":85,"count":3},{"val":58,"count":3},{"val":74,"count":3},{"val":93,"count":3},{"val":156,"count":3},{"val":120,"count":3},{"val":76,"count":3},{"val":123,"count":2},{"val":108,"count":2},{"val":80,"count":2},{"val":99,"count":2},{"val":104,"count":2},{"val":128,"count":2},{"val":134,"count":2},{"val":138,"count":2},{"val":124,"count":2},{"val":112,"count":2},{"val":20,"count":1},{"val":18,"count":1},{"val":177,"count":1},{"val":163,"count":1},{"val":16,"count":1},{"val":114,"count":1},{"val":14,"count":1},{"val":83,"count":1},{"val":101,"count":1},{"val":97,"count":1}],"sfreq_counts":[{"val":500.0,"count":90},{"val":1000.0,"count":46},{"val":1600.0,"count":10},{"val":513.0,"count":4},{"val":499.7071,"count":2},{"val":256.0,"count":2}],"stats_computed_at":"2026-05-31T19:34:32.601226+00:00","total_duration_s":497496.1294318212,"author_year":"Herrema2024_Free_Recall","canonical_name":null,"bad_channels_info":null,"acknowledgements":"We thank our collaborators who have helped in the collection of this data: Hospital of the University of Pennsylvania, Thomas Jefferson University Hospital, Dartmouth-Hitchcock Medical Center, Mayo Clinic, Columbia University Hospital, Emory University Hospital, University of Texas Southwestern Medical Center.","associated_paper_meta":{"channel":"search","confidence":"medium","author_overlap":1,"is_oa":true,"oa_status":"gold","source":"paper_resolver"}}}