Statistical analyses in Figures 1-6
| Figure location | Behavioral test | Statistical test used | Variables/comparisons | Degree of freedom | Test value | p value |
|---|---|---|---|---|---|---|
| 1B | Self-administration | Two-way ANOVA | Session | 780 | 1.8 | 0.07 |
| Lever | 780 | 349.3 | <0.0001 | |||
| Interaction | 780 | 0.8 | 0.60 | |||
| Extinction | Two-way ANOVA | Session | 1092 | 3.2 | <0.001 | |
| Lever | 1092 | 103.7 | 0.0001 | |||
| Interaction | 1092 | 1.1 | 0.33 | |||
| Bonferroni’s post hoc | Active vs inactive lever: session 1 | 1092 | 5.1 | <0.0001 | ||
| Bonferroni’s post hoc | Active vs inactive lever: session 2 | 1092 | 4.0 | 0.0009 | ||
| Bonferroni’s post hoc | Active vs inactive lever: session 3 | 1092 | 3.4 | 0.0096 | ||
| Bonferroni’s post hoc | Active vs inactive lever: session 4 | 1092 | 3.2 | 0.019 | ||
| Bonferroni’s post hoc | Active vs inactive lever: session 5 | 1092 | 2.7 | 0.28 | ||
| Bonferroni’s post hoc | Active vs inactive lever: session 6 | 1092 | 3.2 | 0.02 | ||
| Bonferroni’s post hoc | Active vs inactive lever: session 7 | 1092 | 2.4 | 0.29 | ||
| Bonferroni’s post hoc | Active vs inactive lever: session 8 | 1092 | 1.4 | 0.90 | ||
| Bonferroni’s post hoc | Active vs inactive lever: session 9 | 1092 | 2.7 | 0.10 | ||
| Bonferroni’s post hoc | Active vs inactive lever: session 10 | 1092 | 3.1 | 0.03 | ||
| Bonferroni’s post hoc | Active vs inactive lever: session 10 | 1092 | 2.7 | 0.09 | ||
| Bonferroni’s post hoc | Active vs inactive lever: session 10 | 1092 | 1.6 | 0.82 | ||
| Bonferroni’s post hoc | Active vs inactive lever: session 10 | 1092 | 1.7 | 0.75 | ||
| Bonferroni’s post hoc | Active vs inactive lever: session 10 | 1092 | 1.4 | 0.90 | ||
| None | Self-administration (reinforced vs non-reinforced) | Two-way ANOVA | Session | 740 | 1.74 | 0.08 |
| Group (reinforced, non-reinforced) | 740 | 13.6 | 0.0002 | |||
| Interaction | 740 | 1.16 | 0.32 | |||
| None | Self-administration (reinforced vs non-reinforced) | Bonferroni’s post hoc | Reinforced vs non-reinforced, all sessions | 740 | 0.44–2.22 | 0.27 to >0.999 |
| 2A | Self-administration: sex differences, active lever pressing | Two-way ANOVA | Sex (male, female) | 360 | 1.64 | 0.20 |
| Session | 360 | 1.30 | 0.24 | |||
| Interaction | 360 | 0.33 | 0.97 | |||
| 2B | Self-administration: sex differences, inactive lever pressing | Two-way ANOVA | Sex (male, female) | 360 | 0.63 | 0.77 |
| Session | 360 | 8.57 | 0.004 | |||
| Interaction | 360 | 0.21 | 0.99 | |||
| 2B | Self-administration: sex differences, inactive lever pressing | Bonferroni’s post hoc | Male vs female all sessions | 360 | 0.37–1.55 | >0.999 |
| 2C | Self-administration: sex differences, infusions | Two-way ANOVA | Sex (male, female) | 360 | 0.34 | 0.56 |
| Session | 360 | 3.47 | 0.004 | |||
| Interaction | 360 | 0.31 | 0.97 | |||
| 2C | Self-administration: sex differences, infusions | Bonferroni’s post hoc | Male vs female: all sessions | 360 | 0.03–1.08 | >0.999 |
| 2D | Self-administration: sex differences, total number of infusions | Unpaired Student’s t test | Sex (male, female) | 36 | 0.25 | 0.80 |
| 2E | Extinction: sex differences, active lever pressing | Two-way ANOVA | Sex (male, female) | 504 | 2.55 | 0.11 |
| Session | 504 | 2.28 | 0.006 | |||
| Interaction | 504 | 0.75 | 0.71 | |||
| 2E | Extinction: sex differences, active lever pressing | Bonferroni’s post hoc | Male vs female: all sessions | 504 | 0.02–1.67 | >0.999 |
| 2F | Extinction: sex differences, inactive lever pressing | Two-way ANOVA | Sex (male, female) | 504 | 5.46 | 0.02 |
| Session | 504 | 0.70 | 0.76 | |||
| Interaction | 504 | 0.48 | 0.93 | |||
| 2F | Extinction: sex differences, inactive lever pressing | Bonferroni’s post hoc | Male vs female: all sessions | 504 | 0.0007–1.7 | 0.74 to >0.999 |
| 3A | Self-administration: DREADD treatment, active lever pressing | Two-way ANOVA | Treatment (Gs, Gi, control) | 350 | 8.72 | 0.0002 |
| Session | 350 | 1.21 | 0.29 | |||
| Interaction | 350 | 0.56 | 0.92 | |||
| 3B | Self-administration: DREADD treatment, inactive lever pressing | Two-way ANOVA | Treatment (Gs, Gi, control) | 350 | 6.65 | 0.002 |
| Session | 350 | 1.04 | 0.411 | |||
| Interaction | 350 | 0.65 | 0.86 | |||
| 3C | Self-administration: DREADD treatment, infusions | Two-way ANOVA | Treatment (Gs, Gi, control) | 350 | 0.57 | 0.56 |
| Session | 350 | 3.18 | 0.001 | |||
| Interaction | 350 | 0.33 | 0.99 | |||
| 3D | Self-administration: DREADD treatment, total number of infusions | One-way ANOVA | Treatment (Gs, Gi, control) | 35 | 1.25 | 0.90 |
| 3E | Extinction: DREADD treatment, active lever pressing | Two-way ANOVA | Treatment (Gs, Gi, control) | 504 | 12.74 | <0.0001 |
| Session | 504 | 2.21 | 0.008 | |||
| Interaction | 504 | 0.80 | 0.75 | |||
| 3F | Extinction: DREADD treatment, inactive lever pressing | Two-way ANOVA | Treatment (Gs, Gi, control) | 504 | 10.52 | <0.0001 |
| Session | 504 | 0.67 | 0.79 | |||
| Interaction | 504 | 0.21 | >0.99 | |||
| 4C | Reinstatement | Two-way ANOVA | Treatment (Gs, Gi, control) | 70 | 8.43 | 0.0005 |
| Session | 70 | 13.24 | 0.0005 | |||
| Interaction | 70 | 6.84 | 0.0019 | |||
| 4C | Bonferroni’s post hoc | Control extinction vs control reinstatement | 70 | 4.43 | 0.0005 | |
| 4C | Bonferroni’s post hoc | Gs extinction vs Gs reinstatement | 70 | 2.2 | 0.03 | |
| 4C | Bonferroni’s post hoc | Gi extinction vs Gi reinstatement | 70 | 0.55 | 0.999 | |
| 4D | A/N ratio | Ordinary one-way ANOVA | Treatment (Gs, Gi, control) | 25 | 5.7 | 0.009 |
| 4D | Bonferroni’s post hoc | Control vs inhibitory | 25 | 3.3 | 0.009 | |
| 5A | Membrane capacitance | Ordinary one-way ANOVA | Treatment (Gs, Gi, control) | 25 | 0.38 | 0.69 |
| 5B | Resting membrane potential | Ordinary one-way ANOVA | Treatment (Gs, Gi, control) | 25 | 3.3 | 0.054 |
| 5C | NMDA decay | Ordinary one-way ANOVA | Treatment (Gs, Gi, control) | 25 | 5.7 | 0.009 |
| 6 | Reinstatement active lever pressing correlation to A/N | Linear regression analysis | Active lever pressing vs A/N ratio | 26 | 12.37 | 0.002 |
Bolded values indicate statistical significance.