Skip to main content
. Author manuscript; available in PMC: 2012 Aug 11.
Published in final edited form as: Brain Res. 2011 Jun 26;1406:43–58. doi: 10.1016/j.brainres.2011.06.048

Table 2.

Mean DKM parameter κ (s-1), mean reproduced length (s) and coefficient of variation of the duration reproduction task for three durations, as well as discounting parameter k compared between stimulant-using, impulsive subjects as well as stimulant-naïve controls.

Ever used
Popular types
Stimulant users (n = 10) Impulsive (n = 5) Controls (n = 12)
Mean S.D. Mean S.D. Mean S.D.
BIS non-planning 25.2 6.6 26 0.7 21 4
BIS motor 24.8 6.2 32 5.6 21 4.1
BIS attention/cognition 16.6 3.8 21.4 4.4 15 3.2
ZTPI present-hedonistic 54.3 4.5 59.2 5.8 54.8 6.4
ZTPI present fatalistic 22 5.2 27.2 3.7 21 5.1
ZTPI future 40.9 7.7 35.6 9.8 44.6 6.3
DKM parameter κ 0.0128 0.0052 0.0302 0.0141 0.0092 0.0007
3-s mean reproduction 2.821 0.312 2.706 0.762 3.004 0.523
3-s CV reproduction 30.6 11.1 24.3 9.1 19.6 4.6
9-s mean reproduction 8.042 1.238 7.178 1.982 8.209 1.249
9-s CV reproduction 26.9 10.1 30.1 10.2 22.7 9.0
18-s mean reproduction 13.760 1.940 11.939 5.503 13.360 2.455
18-s CV reproduction 29.9 13.6 23.2 5.0 30.5 12.2
Discounting parameter k 0.488 0.473 0.053 0.036 0.188 0.119