Table 3.
Group × visit interaction effects for cognitive performance
| Control (N = 40) | Expect Adderall/ receive placebo (N = 40) | Expect Adderall/ receive caffeine (N = 41) | ||||
|---|---|---|---|---|---|---|
|
|
||||||
| M (SE) | F | p | ƞ2p | |||
|
| ||||||
| SRT: Immediate recall | 0.08 | .927 | 0.00 | |||
| Visit 1 | 55.23 (1.21) | 53.15 (1.21) | 55.03 (1.19) | |||
| Visit 2 | 56.13 (1.13) | 53.60 (1.13) | 55.54 (1.12) | |||
| SRT: Short-term recall | 2.80 | .065 | 0.05 | |||
| Visit 1 | 8.23 (0.82) | 7.33 (0.83) | 6.88 (0.81) | |||
| Visit 2 | 6.83 (0.76) | 8.56 (0.77) | 7.59 (0.75) | |||
| SRT: Long-term recall | 0.31 | .734 | 0.01 | |||
| Visit 1 | 41.60 (1.93) | 38.87 (1.95) | 40.66 (1.90) | |||
| Visit 2 | 42.13 (1.84) | 39.10 (1.86) | 42.78 (1.81) | |||
| SRT: Delayed recall | 0.75 | .474 | 0.02 | |||
| Visit 1 | 8.56 (0.41) | 7.97 (0.42) | 8.43 (0.41) | |||
| Visit 2 | 8.53 (0.42) | 7.68 (0.43) | 7.80 (0.43) | |||
| Symbol search | 4.70 | .011 | 0.07 | |||
| Visit 1 | 35.56 (1.03) | 34.25 (1.03) | 35.59 (1.02) | |||
| Visit 2 | 40.83 (1.08) | 42.20 (1.08) | 40.02 (1.07) | |||
| Verbal fluency | 0.01 | .990 | 0.00 | |||
| Visit 1 | 35.65 (1.53) | 36.43 (1.53) | 38.02 (1.51) | |||
| Visit 2 | 37.38 (1.52) | 37.95 (1.52) | 39.56 (1.51) | |||
| CPT: Omission errors | 1.81 | .169 | 0.03 | |||
| Visit 1 | 48.23 (0.91) | 46.58 (0.91) | 46.61 (0.90) | |||
| Visit 2 | 48.70 (1.05) | 47.53 (1.05) | 45.73 (1.03) | |||
| CPT: Commission errors | 1.40 | .250 | 0.02 | |||
| Visit 1 | 53.10 (1.48) | 54.10 (1.48) | 51.73 (1.47) | |||
| Visit 2 | 50.85 (1.61) | 51.88 (1.61) | 47.32 (1.59) | |||
| CPT: HRT block change | 0.25 | .778 | 0.00 | |||
| Visit 1 | 52.55 (1.08) | 51.20 (1.08) | 50.66 (1.06) | |||
| Visit 2 | 51.10 (1.27) | 49.28 (1.27) | 50.29 (1.26) | |||
| PASAT | 0.35 | .708 | 0.01 | |||
| Visit 1 | 67.95 (4.13) | 61.65 (4.02) | 67.71 (3.97) | |||
| Visit 2 | 94.18 (4.97) | 89.20 (4.84) | 97.10 (4.78) | |||
| Stroop: Interference | 0.17 | .844 | 0.00 | |||
| Visit 1 | 171.01 (25.55) | 188.91 (25.23) | 184.58 (24.92) | |||
| Visit 2 | 141.53 (21.74) | 180.28 (21.47) | 159.31 (21.20) | |||
Visit 1 was a control visit where no drug was expected or received. On visit 2, participants completed cognitive assessments between approximately 20–80 min post-drug administration. SRT Selective Reminding Test, CPT Continuous Performance Test, HRT hit response time. CPT scores reflect t-scores