A parity checking circuit is designed for continuous parity checking of content-addressable memory cells, and is configured such that during a parity check the number of parity checking steps per data word is the same as the number of bits in the original payload data word to be stored, with the parity checking circuit being formed from four transistors of the same conductance type. The parity checking circuit has a detector, which automatically detects the change in an information state of a memory cell. The detector is in the form of an automatic state device and has a number of catch latches.