Table 3. Cognitive-task performance.
|
Non-spatial-memory task
|
Spatial-memory task
|
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|---|---|---|---|---|---|---|---|---|
| Subject | difficulty † | single ¶ | dual ¶ | Δ error%§ | difficulty † | single ¶ | dual ¶ | Δ error% § |
| young 01 | 1-to-5 | 2/10 | 8/16 | 30% | 6×6 | 2/10 | 3/16 | -1% |
| young 02 | 1-to-5 | 3/10 | 2/16 | -18% | 4×4 | 2/10 | 1/16 | -14% |
| young 03 | 1-to-5 | 0/10 | 0/16 | 0% | 6×6 | 1/10 | 2/16 | 3% |
| young 04 | 1-to-5 | 1/10 | 4/16 | 15% | 6×6 | 2/10 | 3/16 | -1% |
| young 05 | 1-to-5 | 3/10 | 1/16 | -24% | 7×7 | 2/10 | 4/16 | 5% |
| young 06 | 4-to-12 | 2/10 | 4/16 | 5% | 6×6 | 2/10 | 2/16 | -8% |
| young 07 | 1-to-5 | 3/10 | 4/16 | -5% | 6×6 | 1/10 | 5/16 | 21% |
| young 08 | 1-to-5 | 1/10 | 2/16 | 3% | 6×6 | 0/10 | 3/16 | 19% |
| young 09 | 1-to-3 | 1/10 | 3/16 | 9% | 6×6 | 1/10 | 3/16 | 9% |
| young 10 | 1-to-9 | 2/10 | 5/16 | 11% | 6×6 | 1/10 | 3/16 | 9% |
| older 01 | 1-to-9 | 3/10 | 7/16 | 14% | 6×6 | 2/10 | 14/16 | 68% |
| older 02 | 1-to-3 | 3/10 | 8/16 | 20% | 4×4 | 2/10 | 14/16 | 68% |
| older 03 | 1-to-5 | 2/10 | 1/16 | -14% | 5×5 | 3/10 | 12/16 | 45% |
| older 04 | 1-to-3 | 1/10 | 2/16 | 3% | 5×5 | 1/10 | 9/16 | 46% |
| older 05 | 1-to-9 | 1/10 | 1/16 | -4% | 6×6 | 2/10 | 8/16 | 30% |
| older 06 | 1-to-5 | 2/10 | 4/16 | 5% | 5×5 | 3/10 | 9/16 | 26% |
| older 07 | 1-to-5 | 2/10 | 2/16 | -8% | 4×4 | 2/10 | 7/16 | 24% |
| older 08 | 1-to-5 | 1/10 | 6/16 | 28% | 5×5 | 3/10 | 6/16 | 8% |
| older 09 | 1-to-5 | 3/10 | 10/16 | 33% | 4×4 | 3/10 | 9/16 | 26% |
| older 10 | 1-to-5 | 2/10 | 7/16 | 24% | 4×4 | 3/10 | 9/16 | 26% |
Note: † Non-spatial task difficulty was adjusted by changing the range of possible numbers to be summed (see Figure 3A); spatial-memory task difficulty was adjusted by changing the N×N matrix size (see Figure 3B).
¶ Proportion of trials with error during single-task trials (no balance perturbations) and dual-task trials. Single-task error rates were based on five 5s trials and five 10s trials; dual-task error rates were based on eight trials with a 5s recall-delay interval and eight trials with a 10s recall-delay interval.
§ Difference in percentage error rate (dual-task error rate minus single-task error rate).