Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Hearing Loss ?
    ### Response:
    Presbycusis is common in older adults. Presbycusis comes on gradually as a person ages and mostly affects people over 50. Doctors do not know why presbycusis happens, but it seems to run in families. Presbycusis may make it hard for a person to tolerate loud sounds or to hear what others are saying.
    