“…Researchers use dedicated hardware [ 11 , 12 , 13 ] and experiment with smartphone [ 14 ] or wearable [ 15 , 16 ] technologies, especially with CV signals [ 17 , 18 , 19 ]. Among others, gathered data include physiological signals [ 20 ] (e.g., heart, skin, brain, respiratory system, and eye work), facial expressions [ 21 ], and speech [ 22 , 23 ]. Typically, several signals are collected in order to improve the accuracy of the AI system used for AAER [ 24 ].…”