Sample bias in such things is ridiculous, furthermore, this treads on some pretty shaky ground.

There is a school of thought that cranial capacity correlates positively with intelligence. In essence, the size of a given area of brain matter is predictive regarding the person's capacities. One may find a great deal of such data from people who were intent on proving that some races were intellectually superior to others based upon these "objective" cranial measurements. But the cranial measurements were meaningless in the end because in any given case, there are plenty of people with smaller brains who are smarter than people with larger ones. So the underlying premise was incorrect.

Cro Magnon had a substantially larger brain than modern humans. Just sayin'. Don't believe me? Look it up. Then show me the advanced pace program Cro Magnon developed.

So differences in the size of various regions of gray matter mean little.

Meanwhile, the division between liberal and conservative is contrived in the first place. It is idiotic that a woman would have to vote for someone who would take away her effectual right of self defense in order to secure her right to an abortion; just as it is idiotic that she would have to vote for someone who would start foreign wars on the most flimsy pretext in order to keep her taxes from increasing.

Furthermore, in actual practice of politics, liberals and conservatives may talk different talks, but they walk identical walks.

During the last republican administration when the republicans also controlled congress ... was planned parenthood defunded? no. NPR? no. Welfare? Nope -- it got bigger. Did government get smaller? Nope. Less expensive? Nope. Less intrusive? Nope. The conservative patter is just that -- patter. It is meaningless.

So here we have a study based upon a faulty premise of correlations that has a self-selection bias plus is based upon artificial correspondences to socially defined differences that, in the actual practice of politics, don't exist.