Verbal learning and aging: combined effects of irrelevant speech, interstimulus interval, and education.

Older or lower educated individuals may be less able than younger or higher educated individuals to inhibit irrelevant speech when learning new visual information. In Experiment 1, we investigated the effects of age (four groups), educational attainment (low or high), and verbal noise (spoken words or silence) on word-learning performance in 230 individuals aged 24 to 76 years. Performance was negatively affected by age, lower education, and irrelevant speech, but there were no interactions between age group and noise condition. In Experiment 2, we increased the difficulty of the word-learning task by using both irrelevant speech and a short interstimulus interval (2 or 0.5 s). Age differences became more pronounced as the result of the simultaneous occurrence of irrelevant speech and a short interstimulus interval. This suggests that older individuals may need more time than younger individuals to learn new information in noisy environments.