Table 2.

Baseline ratings

Slow pleasantnessFast pleasantnessSlow intensityFast intensity
Healthy volunteers
    Naloxone
Saline
4.63 ± 3.73
4.05 ± 3.42
t(26) = 0.43, p = 0.67
3.31 ± 3.70
1.42 ± 3.21
t(26) = 1.45, p = 0.16
1.34 ± 0.62
1.53 ± 0.79
t(26) = 0.72, p = 0.48
2.13 ± 0.89
2.42 ± 0.75
t(26) = 0.93, p = 0.36
Chronic pain (FM) patients
    Naloxone
Saline
2.30 ± 3.11
3.19 ± 5.00
t(22) = 0.51, p = 0.62
1.80 ± 3.85
3.54 ± 2.85
t(22) = 1.27, p = 0.22
1.50 ± 0.75
2.05 ± 0.97
t(22) = 1.50, p = 0.15
2.21 ± 0.60
2.08 ± 0.80
t(22) = 0.46, p = 0.65
  • Healthy participants and FM patients rated the pleasantness and intensity of slow (CT-optimal) and fast brushing of the left forearm on the corresponding VAS scales. Mean ratings ± SD at baseline (before any drug administration) are displayed for slow and fast brushing for the naloxone and saline groups for healthy participants and FM patients. The t tests show that before drug infusion, there were no significant differences in ratings between individuals who subsequently received naloxone versus saline.