A Large-Scale Semi-Chronic Microdrive Recording System for Non-Human Primates

Abstract

Multi-electrode recordings in the non-human primate provide a critical method for measuring the widely distributed activity patterns that underlie brain function. However, common techniques rely on small, often immovable arrays, or microdrives, that are only capable of manipulating a small number of closely spaced probes. These techniques restrict the number of cortical areas that can be simultaneously sampled and are typically not capable of reaching subcortical targets. To overcome these limitations, we developed a large-scale, semi-chronic microdrive recording system with up to 256 independently movable microelectrodes spanning an entire cerebral hemisphere. The microdrive system is hermetically sealed, free of internal connecting wires, and has been used to simultaneously record from up to 37 cortical and subcortical areas in awake behaving monkeys for up to 9 months. As a proof of principle, we demonstrate the capability of this technique to address network-level questions using a graph theoretic analysis of functional connectivity data.

Postural Representations of the Hand in Primate Sensorimotor Cortex

“…Monkey 1 was implanted with two Utah electrode arrays (UEAs, Blackrock Microsystems, Inc., Salt Lake City, UT), one in primary motor cortex, the other in somatosensory cortex and four floating microelectrode arrays (FMAs, Microprobes for Life Science, Gaithersburg, MD), two in the anterior and two in the posterior bank of the central sulcus ( Figure S1A). Monkeys 2 through 4 were implanted with semichronic Microdrive electrode arrays (SC96, Gray Matter Research, Bozeman, MT), each spanning large swaths of primary motor and somatosensory cortex and comprising individually depth-adjustable electrodes (Figure S1B-D) (Dotson et al, 2017). All procedures were performed under aseptic conditions and under anesthesia induced with ketamine HCl (20 mg/kg, IM) and maintained with isoflurane (10-25 mg/kg per hour, inhaled).…”

An integrated brain-machine interface platform with thousands of channels

“…Most devices for long-term neural recording are arrays of electrodes made from rigid metals or semiconductors [12,13,14,15,16,17,18]. While rigid metal arrays facilitate penetrating the brain, the size, Young's modulus and bending stiffness mismatches between stiff probes and brain tissue can drive immune responses that limit the function and longevity of these devices [19,11].…”

Monkey EEG links neuronal color and motion information across species and scales

“…Third, studies employing invasive and non-invasive methods in parallel suffer from sparse sampling of recording sites. Massively parallel invasive recordings in multiple brain regions have only recently become viable (Dotson et al, 2017;Jun et al, 2017;Siegel et al, 2015), and EEG recordings in awake behaving animals have so far been limited to relatively few electrodes. This sparsity limits specificity when drawing conclusions from one level to the other.…”