title: Variability of acute extracellular action potential measurements with multisite silicon probes.
abstract: Device miniaturization technologies have led to significant advances in sensors for extracellular measurements of electrical activity in the brain. Multisite, silicon-based probes containing implantable electrode arrays afford greater coverage of neuronal activity than single electrodes and therefore potentially offer a more complete view of how neuronal ensembles encode information. However, scaling up the number of sites is not sufficient to ensure capture of multiple neurons, as action potential signals from extracellular electrodes may vary due to numerous factors. In order to understand the large-scale recording capabilities and potential limitations of multisite probes, it is important to quantify this variability, and to determine whether certain key device parameters influence the recordings. Here we investigate the effect of four parameters, namely, electrode surface, width of the structural support shafts, shaft number, and position of the recording site relative to the shaft tip. This study employs acutely implanted silicon probes containing up to 64 recording sites, whose performance is evaluated by the metrics of noise, spike amplitude, and spike detection probability. On average, we find no significant effect of device geometry on spike amplitude and detection probability but we find significant differences among individual experiments, with the likelihood of detecting spikes varying by a factor of approximately three across trials.
authors.affiliation: Division of Biology, California Institute of Technology, Pasadena, USA.
authors.forename: Kimberly M
authors.initials: KM
authors.lastname: Scott
authors.forename: Jiangang
authors.initials: J
authors.lastname: Du
authors.forename: Henry A
authors.initials: HA
authors.lastname: Lester
authors.forename: Sotiris C
authors.initials: SC
authors.lastname: Masmanidis
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D000704:Analysis of Variance; D000818:Animals; D015374:Biosensing Techniques; D056547:CA1 Region, Hippocampal / Q000502:physiology; D056654:CA3 Region, Hippocampal / Q000502:physiology; D003627:Data Interpretation, Statistical; D018891:Dentate Gyrus / Q000502:physiology; D055724:Electrophysiological Phenomena; D004595:Electroplating; D004867:Equipment Design; D005071:Evoked Potentials / Q000502:physiology; D005110:Extracellular Space / Q000502:physiology*; D006046:Gold; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008839:Microelectrodes; D008904:Miniaturization; D012825:Silicon
chemical_list: D006046:Gold; D012825:Silicon