MEA Channel Mapping

The MEA Mapping feature remaps physical electrode indices to logical channel numbers used throughout the app — in the Studio, Signal Viewer, Heatmap, and Raster panels.

This is necessary because MEA electrodes are rarely wired in sequential order to the acquisition hardware inputs. A mapping tells the app which logical channel index corresponds to which physical electrode position on the array.

Why It Matters

Without a mapping, channel 0 in the app corresponds to acquisition input 0, channel 1 to input 1, and so on — but these inputs may not correspond to adjacent electrodes on your MEA. The result is that spatial visualisations (Heatmap in MEA 8×8 layout, Signal Viewer in MEA 8×8 layout) would show a scrambled electrode map.

With a correct mapping applied, the app translates logical channel indices to physical grid positions, so the MEA 8×8 layout correctly reflects the physical arrangement.

Opening the MEA Mapping Modal

Click the MEA Mapping button in the app toolbar. The modal shows a grid representing the MEA layout with draggable channel assignments.

Available Layouts

Layout	Description
8×8 (64 electrodes)	Full 8×8 grid. Use when your MEA has up to 64 electrodes and the system is configured with 32–64 channels.
4×8 (32 electrodes)	Half-grid layout for 32-channel recordings.
Custom	Freely assign any channel to any grid position.

Configuring a Mapping

1. Select a base layout from the dropdown.
2. For each grid cell, drag the channel index badge to the correct physical electrode position, or type the channel number directly into the cell.
3. Unused electrode positions can be left empty (they appear greyed out in visualisations).
4. Click Apply to activate the mapping.

Saving and Loading Mappings

• Save: click Export to save the current mapping to a .json file.
• Load: click Import to load a previously saved mapping file.
• The last-applied mapping is remembered between app sessions.

Effect on Panels

Panel	Effect
Signal Viewer	MEA 8×8 layout places channels at their physical electrode positions
Heatmap	MEA 8×8 layout shows spatial activity in electrode coordinates
Raster	Channel labels reflect electrode positions (optional)
Studio	Channel indices in blocks refer to logical channels, not physical positions

Tips

• If you are unsure of your wiring order, run a simple test: apply a known signal to one electrode at a time and watch which channel responds in the Signal Viewer. Note the channel number, then assign it to the correct grid position in the mapping.
• For standard commercial MEAs, wiring diagrams are usually available in the manufacturer's documentation.
• The mapping only affects display — it does not change how data is acquired or stored.