Table 1. Participant Characteristics for the Aim 1 (behavioral) Sample (n=63) and the Aim 2 (fMRI) Sample (n=38).
| Aim 1: behavioral sample (n=63) | Aim 2: fMRI sample (n=38) | |
|---|---|---|
| Gender (M:F) | 40:23 | 22:16 |
| Age | 25.1 (3.4) | 24.9 (2.7) |
| Education (years) | 15.3 (1.6) | 15.7 (1.6) |
| Race | ||
| Caucasian | 37 | 23 |
| More than one race | 9 | 7 |
| African-American | 8 | 4 |
| Asian | 7 | 4 |
| Hawaiian/Pacific Islander | 1 | – |
| Not reported | 1 | – |
| Current substance use | ||
| Alcohol (drinks/week) | 7.3 (6.7) | 7.0 (6.0) |
| Cigarettes (per day) | 1.0 (1.5); n=21 | 1.1 (2.0); n=13 |
| Caffeine (cups/day) | 1.6 (1.0); n=57 | 1.7 (1.1); n=35 |
| Marijuana (times/month) | 16.4 (17.2); n=30 | 7.0 (8.9); n=12 |
| Lifetime substance use (% ever used) | ||
| Marijuana | 84.1% | 84.2% |
| Hallucinogens | 38.1% | 31.6% |
| Stimulants | 31.7% | 26.3% |
| Opiates | 23.8% | 18.4% |
| MDMA | 22.2% | 21.1% |
| Sedatives | 17.5% | 7.9% |