multielektrodearrays

Multielectrode arrays (MEAs) are devices that integrate multiple electrical contacts on a single substrate to record or stimulate neural activity from tissue. By providing simultaneous access to many sites, MEAs enable high-resolution measurements of neural dynamics across populations of neurons in time and space. They are used in both in vitro and in vivo contexts, supporting studies of network behavior, synaptic function, and circuit mechanisms.

MEA formats vary in geometry and application. Planar arrays place a two-dimensional grid of recording pads on a flat substrate for surface or shallow tissue recordings. Penetrating arrays, such as the Utah array (a 10×10 silicon grid) and Michigan probes (shanks with multiple electrode sites), insert contacts into neural tissue to capture single-unit activity and local field potentials. More recently, flexible polymer and carbon fiber assemblies offer alternative geometries and improved biocompatibility for chronic implantation, reducing mechanical mismatch with brain tissue and enabling long-term recordings.

Applications include basic neuroscience research, pharmacology screening, and clinical neuroprosthetics. In vitro cultures and brain slices are commonly studied with planar MEAs to map network activity and pharmacological effects; in vivo MEAs enable brain–machine interfaces and neuromodulation experiments. High channel counts and integrated data acquisition support real-time decoding of movement intentions or sensory signals, as well as closed-loop stimulation paradigms.

Challenges include tissue reaction such as gliosis and impedance changes that can degrade signal quality over time, mechanical mismatch, and limitations in chronic stability. Data handling and spike sorting for hundreds of channels add analytical complexity. Ongoing advances seek to improve biocompatibility, chronic reliability, and scalable manufacturing of multielectrode arrays.