What is a Multi-Electrode Array?
Multi-electrode array is an array of microscopic electrodes distributed over a small surface area at the bottom of a glass or plastic multi-well plate or a single well (chip). Electroactive cells, such as neurons or cardiomyocytes, can be cultured over the electrodes forming cohesive networks over time. The functional behavior of any neural network can be captured to identify the electrical activity – spontaneous or induced (electrical stimulation) neuronal firing. MEA is the extracellular recording of action potentials, otherwise known as field potentials. Scientists typically use MEA to:
- Track stem cell development or differentiations
- Develop and use brain slices, tissues, or cellular cultures for disease modeling
- Assess pharmacological manipulations for drug or phenotypic screening
How Does a Multi-Electrode Array Work?
Brain slices, tissues, or cells cultured over a microelectrode array will produce an extracellular field potential (voltage changes) that are subsequently recorded. If the tissues or cells do not have spontaneous activity, electrical stimulation can be applied to induce voltage changes. These voltage changes are signal processed to a single neuronal structure (waveform) decoding neural connectivity and frequency of firing.
Multi-electrode Recording From a Cerebellar Cortex Slice
Figure 1: Multi-electrode recording from a cerebellar cortex slice. Purkinje cell firing from each electrode can be monitored simultaneously and segregated to illustrate stable field potential firing of a single Purkinje neuron.
Macroscopic View of Neural Networks
MEA data provides a macroscopic view of neural networks, much like electroencephalogram (EEG) monitors electrical activity of the whole brain. The concept and the readout of EEG is similar to MEA; however, it is much larger scale in that the electrodes cover the entire brain. Our EEG services allow for a macroscopic recording of seizure animal models and sleep-wake monitoring.
Frequently Asked Questions (FAQs) for Multi-Electrode Array Electrophysiology
What is the difference between Multi-electrode array and patch clamp electrophysiology?
MEA records the field potential electrical activity from the extracellular space of a population of neurons whereas patch clamp electrophysiology records the action potential electrical activity from the intracellular space of a single neuron.
What are the benefits to using Multi-electrode array in my studies?
MEA generates high-throughput readout of neuronal populations with the placement of multiple electrodes recording at once rather than individually. The experimental design accumulates data simultaneously from multiple sites within the array. It can be done in live tissues and cells and repeated over time since it is also non-invasive. MEA’s provides a fast functional readout of neurons plated very much the same way they are cultured for any other assay in a plate or dish.