Table 1.
Means (and standard errors) of participant characteristics
| Measure | Yngnone | Yngacc | Yngrt | Yngboth | Oldnone | Oldacc | Oldrt | Oldboth |
|---|---|---|---|---|---|---|---|---|
| Age | 19.0 (.48) | 20.1 (.46) | 19.1 (.50) | 19.2 (.47) | 67.0 (.48) | 66.3 (.47) | 66.8 (.48) | 67.5 (.47) |
| Education1 | 12.7 (.28) | 13.4 (.27) | 12.6 (.29) | 12.9 (.28) | 15.1 (.29) | 15.0 (.28) | 16.1 (.28) | 16.0 (.28) |
| Medications1 | 1.0 (.24) | 1.0 (.23) | 0.5 (.24) | 0.7 (.23) | 2.7 (.24) | 2.8 (.23) | 3.4 (.24) | 2.5 (.23) |
| Vocabulary1 | 27.8 (.51) | 28.2 (.49) | 30.0 (.52) | 28.2 (.50) | 34.0 (.52) | 33.3 (.50) | 33.8 (.52) | 34.1 (.50) |
| Digit Symb1 2 | 63.7 (1.6) | 62.8 (1.6) | 58.1 (1.7) | 61.7 (1.6) | 45.5 (1.7) | 47.3 (1.6) | 50.9 (1.7) | 45.1 (1.6) |
| DS Memory1 | 7.8 (.28) | 8.0 (.27) | 7.8 (.29) | 8.0 (.27) | 5.9 (.28) | 5.3 (.28) | 5.9 (.28) | 5.0 (.28) |
Notes. Education = number of years of education completed. Medications = self- reported number of daily medications taken. Vocabulary = number correct out of 40 on the Shipley Vocabulary Test (Zachary, 1986). Digit Symb = WAIS Digit-symbol subtest (Wechsler, 1981). Digit Symbol Memory = symbol recall memory following the WAIS Digit-symbol subtest (Wechsler, 1981). Conditions: none = no feedback, acc = accuracy feedback only, rt = speed feedback only, and both = both accuracy and speed feedback.
1
Age comparison p < .01.
2
Age x Condition interaction p < .01.