Participant demographics and mean cognitive performance
| Age group | Young | Middle | Older |
|---|---|---|---|
| N | 35 | 37 | 39 |
| Age range (years) | 22–45 | 46–64 | 65–87 |
| Sex (male/female) | 17/18 | 18/19 | 20/19 |
| Highest education | |||
| University | 30 | 23 | 19 |
| A′ levels | 4 | 9 | 11 |
| GCSE grade | 1 | 5 | 5 |
| None >16 | 0 | 0 | 4 |
| Proportion of tones | 0.99 (0.03) | 0.93 (0.11) | 0.89 (0.16) |
| MMSE | 29.34 (1.1) | 29.08 (0.9) | 28.08 (1.5) |
| Crystallized intelligence | 53.71 (3.9) | 54.38 (4.8) | 53.23 (5.8) |
| Fluid intelligence | 37.31 (4.4) | 33.32 (4.6) | 27.28 (5.5) |
Values in parentheses are standard deviations. Proportion of tones detected on Siemens HearCheck Screener test; MMSE, Mini mental status examination; Crystallized intelligence, Spot-the-Word test; Fluid intelligence, Cattell culture fair test.