Both would be OK, but - That smell takes me back to my childhood sounds better to me. You could also say that that reminds me of my childhood, my mom's cooking, when I was little, etc.

Both are grammatically acceptable, but "takes" is more natural and commonly used.

Both sentences are correct, but they have slightly different nuances: * "That smell takes me back to my childhood" suggests that the smell mentally transports you to your childhood memories. * "That smell brings me back to my childhood" has a similar meaning but can imply a more emotional connection, as if the smell brings those memories closer to you. Both are commonly used, so you can choose based on the tone you prefer.

I think 'takes me back' if you are 'going back' to your childhood, but 'brings back my childhood' if your childhood is coming back to you.

Agreed. Both would be equally acceptable. I might lean a little more to "brings me back", but only from personal preference, not due to a "better" collocation.