A few weeks ago, John McCain seemed to be having a bit of word-finding problems (dysnomia) and was a bit confused as evidenced on some broadcast senate hearings. 3 days ago he underwent surgery for a blood clot (hematoma) in the left frontal lobe. At age 80, this isn't so surprising, as due to brain shrinkage (atrophy) blood clots can often form after minor trauma. Most clots are benign, in the sense that they are unassociated by other brain abnormalities.