Flexible, foldable, actively multiplexed, high-density electrode array for mapping brain activity in vivo


Arrays of electrodes for recording and stimulating the brain are used throughout clinical medicine and basic neuroscience research, yet are unable to sample large areas of the brain while maintaining high spatial resolution because of the need to individually wire each passive sensor at the electrode-tissue interface. To overcome this constraint, we developed new devices that integrate ultrathin and flexible silicon nanomembrane transistors into the electrode array, enabling new dense arrays of thousands of amplified and multiplexed sensors that are connected using fewer wires. We used this system to record spatial properties of cat brain activity in vivo, including sleep spindles, single-trial visual evoked responses and electrographic seizures. We found that seizures may manifest as recurrent spiral waves that propagate in the neocortex. The developments reported here herald a new generation of diagnostic and therapeutic brain-machine interface devices.

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Figure 1: Flexible, high-resolution multiplexed electrode array.
Figure 2: Animal experiment using feline model.
Figure 3: Spontaneous barbiturate-induced sleep spindles.
Figure 4: Visual evoked response analysis to a two-dimensional sparse noise visual stimulus.
Figure 5: Detailed two-dimensional data from electrographic seizures in feline neocortex.


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This work was supported by the National Science Foundation (grant DMI-0328162) and the US Department of Energy, Division of Materials Sciences (Award No. DE-FG02-07ER46471), through the Materials Research Laboratory and Center for Microanalysis of Materials (DE-FG02-07ER46453) at the University of Illinois at Urbana-Champaign. J.A.R. acknowledges a National Security Science and Engineering Faculty Fellowship. Work at the University of Pennsylvania was supported by grants from the US National Institutes of Health (National Institute of Neurological Disorders and Stroke RO1-NS041811 and RO1-NS48598), the Julie's Hope Award from the Citizens United for Research in Epilepsy, and the Dr. Michel and Mrs. Anna Mirowski Discovery Fund for Epilepsy Research. J.V. received a Ruth L. Kirschstein National Research Service Award (2T32HL007954) from the US National Institutes of Health, National Heart, Lung and Blood Institute.

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J.V., D.-H.K., L.V., A.E.A., V.R.T., L.P., J.V.S., D.C., J.A.R. and B.L. designed the experiments. J.V., D.-H.K., L.V., J.A.B., Y.-S.K., S.-W.H., A.C.V., D.F.W., K.D., E.S.F., C.E.G., R.Y., J.W. and J.X. performed the experiments and analysis. J.V., D.-H.K., L.V., J.A.B., E.S.F., Y.H., D.C., J.A.R. and B.L. wrote the paper.

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Correspondence to John A Rogers or Brian Litt.

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Supplementary Text and Figures

Supplementary Figures 1–27 (PDF 11216 kb)

Supplementary Movie 1

Movie of a short electrographic seizure showing numerous complicated spatial patterns, including clockwise and counterclockwise spiral waves. The voltage for all 360 channels is plotted as a color map in the top of the frame, while the average of all 360 electrodes is plotted at the bottom of the frame with a vertical bar indicating the position in time for reference. The movie is presented ~18× slower than real-time. (MPG 29888 kb)

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Viventi, J., Kim, D., Vigeland, L. et al. Flexible, foldable, actively multiplexed, high-density electrode array for mapping brain activity in vivo. Nat Neurosci 14, 1599–1605 (2011). https://doi.org/10.1038/nn.2973

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