AMA #2: Lizard brain, seeking and pleasure circuits, meditation and intrusive thoughts

We're back with another Ask Us Anything! On this episode of The Social Brain, we will be addressing questions about all things #neuroscience sent to us by viewers like you.

1. I want to know the difference between the limbic brain and the reptilian brain. Are they the same or [do they] operate differently?
2. Can you discuss the interplay between the desire circuitry and pleasure circuits, is there an overlap? Could you discuss the nuclei? What circuits act in opposition to these circuits?
3. About to go on a 10-day vipassana meditation silent retreat. Was wondering what the likely effects are of spending 10 days meditating / making the most of it?
4. Why do I have intrusive thoughts?
5. Where in the brain would you go on the magic school bus and why?
6. What are some resources for learning about neuroscience?