Several studies outline a future scenario of longer working lives and later retirement, meaning that there could be a large number of elderly workers in offices. Add to this the natural effect of hearing loss due to ageing (presbycusis; which usually presents after the 5th decade of life) and you have an open door to questions regarding the acoustic comfort of this group. In a first study, it was shown that the effect of intelligible speech on performance in a serial recall task is similar for listeners with normal hearing and presbycusis. The aim of this new experiment is to assess whether any differences might occur when people are involved in a more ecologically valid task (long exposure to noise - 3 h/condition - and similar tasks to those performed in open-plan offices). Given the validation of a hearing loss simulator in previous studies, this one will be used to reproduce the group of people with mild hearing loss (onset of presbycusis). Therefore, the same group of people (32 participants) with normal hearing will perform the experiment under two listening conditions, with and without the simulator. Each listening condition will have two noise conditions, irrelevant speech, each with a different intelligibility level.