According to the latest list published by the United States Trademark and Patent Office (USPTO), Apple has obtained an AirPods related design patent, which can monitor electroencephalogram (EEG), (EMG), (EOG) and other biological signals.

Citing Apple's patent report, the AirPods housing and headphone end can be equipped with multiple active electrodes and reference electrodes, which can be configured to measure the biological signals and electrical activity of the wearer's brain.

Apple will indicate that in order to monitor EEG brain activity more accurately, it needs to be customized for the wearer's ear shape, so as to ensure that the sensor fits the wearer's ear canal better and the monitoring data is accurate.