Symptoms of significant brain atrophy include progressive cognitive impairment involving multiple cognitive functions, otherwise known as dementia, seizures and aphasia, which is the disruption in the understanding or production of language or both.
The Senate majority leader has somewhat less official power than the Speaker of the House. This is because the vice president is technically the Senate's presiding officer, a ceremonial position that calls chiefly for casting a vote in the event of a tie.
Much has been made in the press lately of Senator Majority Leader Harry Reid's (D-NV) sway over the legislative agenda. No doubt, the largest measure of control over what is taken up for debate and what is voted on belongs to the Senate Majority Leader, regardless of the Senator holding that position.