Party of Fear vs. Party of Psychopaths
I agree with you about the last election. From vampire capitalism to the war on women it was a fear campaign.
The Daisy ad, arguably the most extreme example of its type, was put out by the Johnson campaign in 1964. And yet each election cycle we hear far more about the Willie Horton ad, which looks quite reasonable by comparison.
At the same time there is a definite push by the left to present conservatives as the party of fear and progressives as the party of data. Jon Stewart's rally in DC assumed this as a framework. I think it has become conventional wisdom among political writers on the left. The Tomasky article I highlighted shows it's lurking just beneath the surface as a grand unified theory of conservative mendacity.
Meanwhile there is no one on the right arguing the contrary, i.e. a shrunken amygdala might explain the behavior of some progressives. Think of high profile individuals who are superficially charming, manipulative, seem to have a grandiose view of themselves and exhibit impulsive, immoral (perhaps even illegal) sexual behavior at tremendous personal and professional risk to themselves. I can immediately think of 5-6 nationally known Democrats who might fit the bill. It's not a diagnosis but it is the kind of broad correlation of behavior which is considered significant when applied to conservatives.
Despite this you're unlikely to see any discussion of progressive behavior in unflattering medical terms. Has it ever occurred to folks like Michael Tomasky that there might be another side to the narrative about brains and politics? It doesn't seem that way.