Table 1.
Interactions between day and attentional vulnerability on performance.
| Outcome | Predictor | Interaction | By Vulnerability | |||||
|---|---|---|---|---|---|---|---|---|
| b (SEM) | ΔR2 | Level | b (SEM) | ΔR2 | ||||
| PVT | ||||||||
| Lapses§ | Day2 | − .052*** | (.011) | .045 | LV | − .06 | (.07) | .001 |
| MV | − .55*** | (.07) | .101 | |||||
| VOLT | ||||||||
| Correct responses | Day | − .006 | (.007) | .001 | Mean | − .08** | (.03) | .010 |
| Hits | Day | − .005 | (.005) | .001 | Mean | − .09*** | (.02) | .021 |
| Correct rejections | Day | − .002 | (.004) | < .001 | Mean | .01 | (.02) | .001 |
| Median RT, correct (ms) | Day | .429 | (.577) | .001 | Mean | − 15.58*** | (2.57) | .049 |
| Response confidencea | ||||||||
| Incorrect responses | Day | .046 | (.124) | < .001 | Mean | 1.39** | (.49) | .014 |
| Misses | Day | −.107 | (.161) | .001 | Mean | 1.57** | (.60) | .014 |
| False alarms | Day | .142 | (.247) | .001 | Mean | .48 | (.95) | .001 |
| F2B | ||||||||
| Accuracyb | Day | − .056** | (.020) | .011 | LV | .52*** | (.13) | .022 |
| MV | < .01 | (.13) | < .001 | |||||
| Sensitivityb | Day | − .189** | (.063) | .013 | LV | 2.22*** | (.41) | .040 |
| MV | .46 | (.41) | .002 | |||||
| Specificityb§ | Day | − .013 | (.016) | .001 | Mean | − .10 | (.07) | .003 |
| Median RT, hits (ms) | Day | .969** | (.353) | .011 | LV | − 10.48*** | (2.28) | .029 |
| MV | − 1.45 | (2.28) | .001 | |||||
| LOT | ||||||||
| Correct responses | Day2 | .001 | (.006) | < .001 | Mean | .08** | (.03) | .013 |
| Rotation errorc (M) | Day2 | < .001 | (.001) | < .001 | Mean | − .01* | (< .01) | .009 |
| Excess clicks, correct (M) | Day2 | − .005** | (.001) | .023 | LV | .06*** | (.01) | .094 |
| MV | .02 | (.01) | .008 | |||||
| Median RT, correct (s)§ | Day2 | − .004** | (.001) | .019 | LV | .02* | (.01) | .060 |
| MV | − .01 | (.01) | .011 | |||||
| DSST | ||||||||
| Throughputd§ | Day2 | .015 | (.010) | .006 | Mean | .20*** | (.04) | .031 |
| Median RT, correct (ms)§ | Day2 | − .190 | (.135) | .003 | Mean | − 2.35*** | (.61) | .020 |
Vulnerability calculated as difference between within-person mean of psychomotor vigilance task (PVT) lapses on last sleep restriction day versus last baseline day, per person (see Fig. 6). For significant day or day2*vulnerability interactions, the effect of day or day2 at lower vulnerability (LV, less vulnerable) and at higher vulnerability (MV, more vulnerable) levels is shown. LV estimates were obtained by re-centering attentional vulnerability at 1 standard deviation (SD) below the mean. MV estimates were obtained by re-centering attentional vulnerability at 1 SD above the mean (N = 15 in all analyses; refer to Statistical Analyses). For non-significant interactions, the effect of day or day2 at the mean of vulnerability is depicted.
ΔR2, change in R2 for model term; b, unstandardized beta; DSST, Digit Symbol Substitution Task (processing speed)49; F2B, Fractal 2-Back (working memory)39; LOT, Line Orientation Task (visuospatial processing)48; LV, less vulnerable; M, mean; MV, more vulnerable; PVT, psychomotor vigilance task (attention)66,67; RT, reaction time; s, seconds; SEM, standard error of the mean; VOLT, Visual Object Learning Task (working memory)40.
aRange: 0 (minimally confident) to 100 (maximally confident).
bRange: 0 (minimally accurate/sensitive/specific) to 100 (maximally accurate/sensitive/specific).
cRange: 0 (no rotation error) to 30 (perpendicular line; highest rotation error).
dNumber correct per minute.
§Model includes time of day.
*p < .05; **p < .01; ***p < .001, two-tailed.