{"dataset":{"id":"51649","dataset_id":"on002761","name":"memoryreplay","description":"This MEG dataset contains neural recordings from human subjects during memory and localizer phases of an experiment investigating memory replay and sequential neural activity patterns. Participants viewed images from multiple stimulus categories and story-ending stimuli while MEG signals were recorded. The dataset includes detailed trigger information for event marking and timing, enabling analysis of neural sequenceness and memory-related brain activity.","owner_user_id":15,"status":"active","github_repo":"nemarDatasets/on002761","concept_doi":"10.82901/nemar.on002761","latest_version_doi":"10.82901/nemar.on002761.v1.0.0","created_at":"2026-06-21 10:00:54","updated_at":"2026-07-10 22:11:49","zenodo_concept_id":null,"is_sandbox":0,"visibility":"public","ezid_status":"public","enrichment_json":"{\n  \"version\": \"2.0\",\n  \"pipeline_stage\": \"validated\",\n  \"title\": \"memoryreplay\",\n  \"description\": \"This MEG dataset contains neural recordings from human subjects during memory and localizer phases of an experiment investigating memory replay and sequential neural activity patterns. Participants viewed images from multiple stimulus categories and story-ending stimuli while MEG signals were recorded. The dataset includes detailed trigger information for event marking and timing, enabling analysis of neural sequenceness and memory-related brain activity.\",\n  \"methods_description\": \"MEG recordings were acquired during two experimental phases: a memory phase and a localizer phase. In both phases, trials began with visual presentation of images from 6 stimulus categories or story-ending stimuli (positive or negative). Memory phase trials included an answer onset approximately 5.5 seconds after stimulus presentation. Localizer phase trials included a 2-second baseline period with word naming prior to picture onset. Visual stimulus timing was calibrated using a photodiode, with approximately 20 ms delay between trigger and visual onset.\",\n  \"license\": \"CC0\",\n  \"dataset_type\": \"raw\",\n  \"authors\": {\n    \"G. Elliott Wimmer\": {\n      \"orcid\": \"0000-0002-2227-119X\"\n    },\n    \"Yunzhe Liu\": {},\n    \"Neža Vehar\": {},\n    \"Timothy E.J. Behrens\": {},\n    \"Raymond J. Dolan\": {}\n  },\n  \"keywords\": [\n    {\n      \"term\": \"MEG\"\n    },\n    {\n      \"term\": \"memory replay\"\n    },\n    {\n      \"term\": \"sequential activity\"\n    },\n    {\n      \"term\": \"neural sequenceness\"\n    },\n    {\n      \"term\": \"episodic memory\"\n    },\n    {\n      \"term\": \"brain imaging\"\n    }\n  ],\n  \"related_identifiers\": [\n    {\n      \"identifier\": \"10.1101/758185\",\n      \"identifier_type\": \"DOI\",\n      \"relation_type\": \"References\"\n    },\n    {\n      \"identifier\": \"https://github.com/nemarDatasets/on002761\",\n      \"identifier_type\": \"URL\",\n      \"relation_type\": \"IsDescribedBy\"\n    },\n    {\n      \"identifier\": \"https://nemar.org/dataexplorer/detail?dataset_id=on002761\",\n      \"identifier_type\": \"URL\",\n      \"relation_type\": \"IsDescribedBy\"\n    },\n    {\n      \"identifier\": \"10.18112/openneuro.ds002761.v1.1.2\",\n      \"identifier_type\": \"DOI\",\n      \"relation_type\": \"IsDerivedFrom\"\n    }\n  ],\n  \"funding_references\": [\n    {\n      \"funder_name\": \"R.D. is supported by Wellcome Trust Investigator Award 098362/ Z/12/Z.\"\n    },\n    {\n      \"funder_name\": \"Y.L. is supported by a UCL Graduate Research Scholarship and an Overseas Research Scholarship.\"\n    },\n    {\n      \"funder_name\": \"The Max Planck University College London Centre is a joint initiative supported by University College London and the Max Planck Society.\"\n    },\n    {\n      \"funder_name\": \"Wellcome Trust\",\n      \"award_number\": \"098362/Z/12/Z\",\n      \"award_title\": \"Investigator Award\"\n    },\n    {\n      \"funder_name\": \"Wellcome Trust\",\n      \"award_number\": \"203147/Z/16/Z\"\n    },\n    {\n      \"funder_name\": \"University College London\"\n    },\n    {\n      \"funder_name\": \"Max Planck Society\"\n    }\n  ],\n  \"resource_type_specific\": \"MEG Dataset\",\n  \"modalities\": [\n    \"meg\"\n  ],\n  \"sizes\": [\n    \"219.1 GB (1805 files)\"\n  ],\n  \"formats\": [\n    \".acq\",\n    \".cfg\",\n    \".cls\",\n    \".gitattributes\",\n    \".hc\",\n    \".hist\",\n    \".infods\",\n    \".json\",\n    \".md\",\n    \".meg4\",\n    \".newds\",\n    \".res4\",\n    \".tsv\",\n    \".yml\"\n  ],\n  \"source_hash\": \"39b0e1d9c265c9e3e469974d953161a069bee907a7837f0876b61e57188c40a9\"\n}","last_activity_at":"2026-06-21 10:00:54","source":"openneuro","source_id":"ds002761","subject_count":25,"modalities":"meg","age_min":null,"age_max":null,"file_size":219129309354,"total_files":2807,"tasks":"loc,mem","metadata_columns_error":null,"staleness_warn_stage":null,"staleness_admin_notified_at":null,"authors":"G. Elliott Wimmer, Yunzhe Liu, Neža Vehar, Timothy E.J. Behrens, Raymond J. Dolan","license":"CC0","readme":"[![DOI](https://img.shields.io/badge/DOI-10.82901%2Fnemar.on002761-blue)](https://doi.org/10.82901/nemar.on002761)\n\nThe MEG files contain a channel with triggers necessary for event marking and timing. Separate event files with onsets are provided in the participant directories for completeness only; the MEG triggers should be used for actual onsets in analysis. The delay between the trigger and the visual onset of an on-screen event sent by the projector is approximately 20 ms, as estimated using a photodiode.\n\nMemory phase triggers: At the onset of a trial, the first trigger represents the category (1-8) of the on-screen image. Categories 1-6 represent actual stimulus categories. Trigger values of 7 and 8 represent the 4 positive and 4 negative story-ending stimuli, respectively. The onset of the answer, approximately 5.5 sec later, is marked by a trigger value of 11.\n\nLocalizer phase triggers: As in the memory phase, at the onset of a trial, the first trigger represents the category (1-8) of the on-screen image. Categories 1-6 represent true categories. Trigger values of 7 and 8 represent the 4 positive and 4 negative story-ending stimuli, respectively. For a baseline, note that for the 2 s prior to picture onset, a word naming that picture was presented on the screen; thus, baseline values should be taken from data more than 2 s before the trigger onset.\n\nMethods note:  a sequenceness analysis step was omitted from the published 2020 Nature Neuroscience paper. The text should have read:  \n\"We next asked whether the βi(Δt) was consistent with a specified 6 × 6 transition matrix by taking the Frobenius inner product between these two matrices (the sum of element-wise products of the two matrices). This resulted in a single number ZΔt, which pertained to lag Δt. For each trial, sequenceness results were then z-scored across lags. Finally, differential forward – backward sequenceness was defined as ZfΔt − ZbΔt.\"","bids_version":"","sessions_count":null,"publish_date":null,"embedding_dirty":0,"license_tier":"public","zarr_status":"ready","zarr_converted_at":"2026-09-07 22:27:02","zarr_store_count":243,"zarr_index_etag":"32bbd951bf09798376108e71b080777d","zarr_source_commit":"9dc267958bf01dd6fb48f068fdf2ceaa42f49da0","archive_status":null,"archive_size":null,"archive_retry_count":0,"records_status":"ready","archive_skip_reason":"dataset 204.1 GB exceeds 100.0 GB archive limit; use direct download","zarr_errors":6,"zarr_failure_count":5,"zarr_deterministic":0,"zarr_failed_at":"2026-09-07 22:27:02","num_dataset_citations":0,"num_datapaper_citations":13,"n_channels":null,"electrode_system":null,"has_hed":0,"hed_version":null,"is_exemplar":0,"bytes_present":219127449547,"data_complete":1,"withdrawn_at":null,"withdrawn_reason":null,"archive_complete":null,"archive_absent_files":null,"archive_declared_files":null,"zarr_pool_breaks":0,"total_recording_duration":102940.79999999997,"recording_duration_min":179.2,"recording_duration_max":593.16,"recording_count":249,"recordings_unavailable":6,"recordings_measured":243,"channel_count_min":414,"channel_count_max":415,"sampling_frequency":null,"power_line_frequency":null,"eeg_reference":null,"placement_scheme":null,"sweep_stamps":"{\"enrichment_updated_at\":\"2026-06-21 10:18:20\",\"metadata_updated_at\":\"2026-06-21 10:18:29\",\"archive_checked_at\":\"2026-06-21 10:18:50\",\"zarr_checked_at\":null,\"records_checked_at\":\"2026-06-21 10:19:23\",\"citations_updated_at\":\"2026-09-09 03:00:11\",\"channel_montage_checked_at\":null,\"hed_checked_at\":\"2026-06-30 04:39:26\",\"data_checked_at\":\"2026-07-29 03:00:27\",\"availability_report_at\":\"2026-07-23 01:12:30\",\"signal_defaults_at\":\"2026-09-02 11:56:42\",\"recording_stats_at\":\"2026-09-08 03:00:51\"}","participants":25,"num_citations":13,"latest_version":"v1.0.0","zarr_verify_status":null,"zarr_verified_at":null,"owner_username":"nemarAdmin","owner_github":"nemarAdmin","file_size_formatted":"204 GB","zarr_data_failures":{"count":5,"detail_ref":"zarr/index.json","pending":1,"discovered":249},"zarr_index_url":"https://zarr.nemar.org/on002761/zarr/index.json","attestation_deposit_type":null,"attestation_key_status":null,"attestation_deidentified":null,"attestation_no_duplicate":null,"attestation_upstream_source":null,"attestation_accepted_at":null}}