TABLE 3.
Means and Standard Deviations for Sensitivity (d′), Response Bias (C), and Response Times (msec) in Probable Alzheimer’s Disease (AD), Possible AD, and Control Participants
| Stimulus Degradation Level
|
||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| DL 2.00
|
DL 2.25
|
DL 2.50
|
||||||||||||||||
| Test Block | 1
|
2
|
3
|
1
|
2
|
3
|
1
|
2
|
3
|
|||||||||
| M | SD | M | SD | M | SD | M | SD | M | SD | M | SD | M | SD | M | SD | M | SD | |
| Sensitivity (d′) | ||||||||||||||||||
| Probable AD | 3.71 | .25 | 3.56 | .52 | 3.48 | .74 | 3.08 | .53 | 3.18 | .54 | 3.35 | .68 | 3.07 | .42 | 2.80 | .37 | 2.65 | .17 |
| Possible AD | 3.97 | .13 | 3.97 | .19 | 3.62 | .55 | 3.47 | .95 | 3.33 | 1.2 | 3.70 | .74 | 3.84 | .41 | 3.74 | .39 | 3.41 | .87 |
| Controls | 4.05 | .12 | 4.02 | .12 | 4.00 | .09 | 3.98 | .17 | 3.91 | .35 | 3.90 | .35 | 3.95 | .22 | 3.80 | .32 | 3.82 | .35 |
| Response bias (C) | ||||||||||||||||||
| Probable AD | .07 | .09 | .03 | .18 | .08 | .12 | .15 | .24 | .22 | .37 | .31 | .30 | .19 | .30 | .22 | .47 | .26 | .52 |
| Possible AD | .18 | .07 | .16 | .10 | .16 | .20 | .30 | .21 | .32 | .21 | .22 | .03 | .13 | .16 | .12 | .14 | .23 | .19 |
| Controls | .21 | .04 | .21 | .07 | .21 | .06 | .21 | .07 | .23 | .13 | .21 | .12 | .22 | .12 | .21 | .18 | .25 | .17 |
| Response times (msec) | ||||||||||||||||||
| Probable AD | 381 | 35 | 416 | 56 | 410 | 39 | 400 | 29 | 418 | 28 | 433 | 46 | 407 | 25 | 423 | 31 | 436 | 35 |
| Possible AD | 374 | 28 | 383 | 25 | 382 | 39 | 389 | 56 | 399 | 51 | 379 | 32 | 377 | 43 | 384 | 33 | 397 | 44 |
| Controls | 380 | 39 | 379 | 37 | 379 | 41 | 400 | 43 | 394 | 39 | 407 | 48 | 402 | 39 | 416 | 47 | 416 | 47 |
Note. Mean values for sensitivity, response bias, and response times, as a function of test block at each degradation level (2.00, 2.25, and 2.50) in probable AD, possible AD, and control participants. DL = degradation level.