DEAFNESS that comes on with increasing years. It is caused by increasing loss of elasticity in the hearing mechanism, combined with the slowing down of the mental processes that accompanies old age. It is characterised by particular difficulty in hearing high notes such as the telephone and the voices of women and children. Hearing in a background of noise is also affected. Miniaturised, transistor ‘within-the-ear’ hearing aids are available that are proving helpful in making life more bearable for the hearing-impaired. (See also AGEING; HEARING AIDS.)