Gelast

Even if we grant that the "gelasts" are getting reduced to the dimensions of a petty sect, the consideration need not deter us from choosing laughter as our theme.

Source: wiktionary

The phenomena presented by the misogelast, or laughter-hater; the agelast, or non-laugher; the gelast, who is the laugher himself, and the hypergelast, who is the laugher gone intemperate, are looked into, and as far as possible accounted for, by Dr. Sully.

Source: wiktionary

So it might well be the other way round; not the agelast or misolgeast is "somewhat insensitive" to the ways of his fellows but the gelast or hypergelast.

Source: wiktionary

A personality profjle of the gelast or agelast has not so far been convincingly established, nor has a pattern of humor been consistently demonstrated in individuals with different personality types.

Source: wiktionary