Dataset Information

A low-cost, scalable, current-sensing digital headstage for high channel count ?ECoG.

ABSTRACT: OBJECTIVE:High channel count electrode arrays allow for the monitoring of large-scale neural activity at high spatial resolution. Implantable arrays featuring many recording sites require compact, high bandwidth front-end electronics. In the present study, we investigated the use of a small, light weight, and low cost digital current-sensing integrated circuit for acquiring cortical surface signals from a 61-channel micro-electrocorticographic (?ECoG) array. APPROACH:We recorded both acute and chronic ?ECoG signal from rat auditory cortex using our novel digital current-sensing headstage. For direct comparison, separate recordings were made in the same anesthetized preparations using an analog voltage headstage. A model of electrode impedance explained the transformation between current- and voltage-sensed signals, and was used to reconstruct cortical potential. We evaluated the digital headstage using several metrics of the baseline and response signals. MAIN RESULTS:The digital current headstage recorded neural signal with similar spatiotemporal statistics and auditory frequency tuning compared to the voltage signal. The signal-to-noise ratio of auditory evoked responses (AERs) was significantly stronger in the current signal. Stimulus decoding based on true and reconstructed voltage signals were not significantly different. Recordings from an implanted system showed AERs that were detectable and decodable for 52 d. The reconstruction filter mitigated the thermal current noise of the electrode impedance and enhanced overall SNR. SIGNIFICANCE:We developed and validated a novel approach to headstage acquisition that used current-input circuits to independently digitize 61 channels of ?ECoG measurements of the cortical field. These low-cost circuits, intended to measure photo-currents in digital imaging, not only provided a signal representing the local cortical field with virtually the same sensitivity and specificity as a traditional voltage headstage but also resulted in a small, light headstage that can easily be scaled to record from hundreds of channels.

SUBMITTER: Trumpis M

PROVIDER: S-EPMC5385258 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

A low-cost, scalable, current-sensing digital headstage for high channel count μECoG.

Trumpis Michael M Insanally Michele M Zou Jialin J Elsharif Ashraf A Ghomashchi Ali A Sertac Artan N N Froemke Robert C RC Viventi Jonathan J

Journal of neural engineering 20170119 2

<h4>Objective</h4>High channel count electrode arrays allow for the monitoring of large-scale neural activity at high spatial resolution. Implantable arrays featuring many recording sites require compact, high bandwidth front-end electronics. In the present study, we investigated the use of a small, light weight, and low cost digital current-sensing integrated circuit for acquiring cortical surface signals from a 61-channel micro-electrocorticographic (μECoG) array.<h4>Approach</h4>We recorded b ...[more]

PMID: 28102827

Similar Datasets

Project description:Micro-electrocorticography (?ECoG) offers a minimally invasive neural interface with high spatial resolution over large areas of cortex. However, electrode arrays with many contacts that are individually wired to external recording systems are cumbersome and make recordings in freely behaving rodents challenging. We report a novel high-density 60-electrode system for ?ECoG recording in freely moving rats.Multiplexed headstages overcome the problem of wiring complexity by combining signals from many electrodes to a smaller number of connections. We have developed a low-cost, multiplexed recording system with 60 contacts at 406 ?m spacing. We characterized the quality of the electrode signals using multiple metrics that tracked spatial variation, evoked-response detectability, and decoding value. Performance of the system was validated both in anesthetized animals and freely moving awake animals.We recorded ?ECoG signals over the primary auditory cortex, measuring responses to acoustic stimuli across all channels. Single-trial responses had high signal-to-noise ratios (SNR) (up to 25 dB under anesthesia), and were used to rapidly measure network topography within ?10 s by constructing all single-channel receptive fields in parallel. We characterized evoked potential amplitudes and spatial correlations across the array in the anesthetized and awake animals. Recording quality in awake animals was stable for at least 30 days. Finally, we used these responses to accurately decode auditory stimuli on single trials.This study introduces (1) a ?ECoG recording system based on practical hardware design and (2) a rigorous analytical method for characterizing the signal characteristics of ?ECoG electrode arrays. This methodology can be applied to evaluate the fidelity and lifetime of any ?ECoG electrode array. Our ?ECoG-based recording system is accessible and will be useful for studies of perception and decision-making in rodents, particularly over the entire time course of behavioral training and learning.

Dataset Information

A low-cost, scalable, current-sensing digital headstage for high channel count ?ECoG.

Publications

A low-cost, scalable, current-sensing digital headstage for high channel count μECoG.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets