A first channel in the substrate underlying a trap gate is biased to cause trapping of holes or electrons in the trap gate and thereby program the memory device to a programmed state. A second channel in the substrate underlying the trap gate and transverse to the first channel is biased to sense the programmed state. For example, biasing a first channel in the substrate underlying the trap gate to cause trapping of holes or electrons in the trap gate and thereby program the memory device to a programmed state may include applying voltages to a first source/drain region and first gate on a first side of the trap gate and to a second source/drain region and a second gate on a second side of the trap gate, and biasing a second channel in the substrate underlying the trap gate and transverse to the first channel to sense the programmed state may include applying voltages to a third source/drain region on a third side of the trap gate and to a fourth source/drain region on a fourth side of the trap gate.