Tis fMRI that reveals the Christmas spirit

Twas a cold night in Denmark, when researchers groused:
“No one is smiling, not even a lab mouse.”
They pondered a study, undertaken with care,
In hopes of finding results they could share.
So a hypothesis they made, and quietly said:
“Could the Christmas spirit be found in the head?”

Ten subjects they gathered, ten control subjects, too,
Asking them: “So, what is Christmas to you?”
Then into the lab, and under the scanner
To see if their brains would highlight the answer.
Subjects watched photos fly by in a flash—
Some pics were of Christmas, done with panache.

In subjects who liked the Christmas-y show,
Their cerebral cortices lit up with a glow!
But, what of those with no Yuletide cheer?
No bright spots on fMRI did appear.
Yet, before researchers concluded: “MRI did the trick!”
Off they went to check their images quick.

Faster than lab rats, the researchers came,
They hooted, and hollered, and called areas by name:
“The somatosensory cortex, and the premotor, too!
The parietal lobules! Now we know what they do!”
This “Christmas spirit” network lit up on the scans
Of subjects who reported ‘good will toward man.’ 

So researchers concluded (over eggnog and beer)
The brain does reveal those of good cheer!
Their findings they shared, to those who would read it.
(Look in the BMJ, if you think that you need it.)
But one last caveat, of course, must be heeded—
The researchers added: “More research is needed!”