A library of human electrocorticographic data and analyses

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Electrophysiological data from implanted electrodes in the human brain are rare, and therefore scientific access to such data has remained somewhat exclusive. Here we present a freely available curated library of implanted electrocorticographic data and analyses for 16 behavioural experiments, with 204 individual datasets from 34 patients recorded with the same amplifiers and at the same settings. For each dataset, electrode positions were carefully registered to brain anatomy. A large set of fully annotated analysis scripts with which to interpret these data is embedded in the library alongside them. All data, anatomical locations and analysis files (MATLAB code) are provided in a shared file structure at https://searchworks.stanford.edu/view/zk881ps0522.

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Fig. 1: Experimental recordings.
Fig. 2: The ECoG signal.

Panel b was adapted from Ramon y Cajal’s cortex drawings.

Fig. 3: An example of basic ECoG changes when a cortical area becomes active.
Fig. 4: Comparison of broadband and ERP changes across the ventral brain surface.
Fig. 5: Methods for localizing electrode position relative to brain anatomy.
Fig. 6: Illustrating a range of analyses for a specific setting.


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I am grateful to J. Ojemann, M. den Nijs, R. Rao and G. Schalk for many years of selfless mentorship during the development of this library. D. Hermes, R. Eisinger and B. Wandell provided many helpful discussions about open data and helped with critical readings of this manuscript. The scientific value of the time spent by our patients at Harborview Hospital in Seattle is immense and I am thankful for their enthusiastic participation. I am financially supported by the Van Wagenen Foundation. Data collection was supported by NSF grant no. BCS-0642848 and NIH grant no. RO1NS065186. The funders had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript.

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Correspondence to Kai J. Miller.

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Peer review information: Primary Handling Editor: Marike Schiffer.

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