That's actually the long head of the triceps, as opposed to the other, or lateral head. One movement that stimulates the long heads great for me is a variation of the skull crusher.
The difference lies in how far up you rest your back on the bench. Whereas in a normal skull crusher your entire back and head are on the bench, in this variation, move further up so your head hangs off and down off the top end of the bench. This will allow you to hold your upper arms in a vertical position, and permit you to take the bar down way past you normally would, all the way to your forehead which is a good 6 inches further down than in a normal skull crusher. Make a conscious effort to keep your elbows in at all times, you'll probably have to take an ego shot and drop the weight. I find this movement works wonders, and I have badass tricep develpment, for what it's worth.
To give credit where credit is due, I believe I got this routine from Charles Poloquin's A Question of Strengh articles in the old MM2K.
Hope this helps... good luck