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.
The Senate and House Majority and Minority Leaders are four members of Congress who are elected as spokespeople for their parties and manage and schedule the business of the Senate and the House. The Senate Majority Leader is Sen. Harry Reid (D-Nev.) and the Senate Minority Leader is Sen. Mitch McConnell (R-Ky.).