It’s kinda like I took a train to the left side of my brain, oh, mayne

from Ed Sheeran & Yelawolf – You Don't Know (For Fuck's Sake) Lyrics on Rap Genius

Meaning

Yela’s been drinking again….

Yela feels like he took a train to the left side of his brain. The left brain holds the compartments for:
“Numerical Computation”:
Estimation, exact calculation, direct fact retrieval, analysis, grammar/vocalbulary, literal (so words), Logic, details, Lenearity, Lists, Names, Science, Sequence, Order, Thinking, writing. Yelawolf feels like all these things have shut off.
He must look a lil' s'thing like

That’s messed up.

Luckily Yela was able to keep the right half of the brain. This happens to be crucial for a rapper… Not saying that every rapper looks like the picture above, but it does come close to the MC’s that don’t do numbers,… like Souja…. (zzzzing?)
“Men Lie, Woman Lie, Numbers Don’t”
If you curious what’s on the right side of the brain…. well it holds the visual-, creative-, Rhythmic-, Artistic-, Intuitive-, Fantasy-, Feeling-, Imaginative-, Impetuous-, Subjective-, Pattern-, Beauty-, Possibilities-, Shapes-, Observation-, “Big Picture”–, Stories-, Pictures-part

When the train awkwardly ran into Yela brain it hurt, badly, I promise.

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