1. A base station apparatus configured to communicate with a terminal apparatus, the base station apparatus comprising:transmission circuitry configured to transmit downlink data by using a physical downlink shared channel (PDSCH) and downlink control information (DCI) through a physical downlink control channel (PDCCH); and
modulation circuitry configured to modulate encoded bits in the PDSCH by using a first modulation mapping or a second modulation mapping and produce modulation symbols, wherein
in a case that the DCI is defined in a prescribed DCI format,
the first modulation mapping is used for modulating the encoded bits, and
the modulation symbols are given based on at least a plurality of bits, the plurality of bits being independent of the encoded bits.