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.
After the parties have held their elections, the selection is made known through the press or by announcement to the Senate. The majority and minority leaders are the elected spokesmen on the Senate floor for their respective political parties, having been elected by their fellow Senators of the same party to whom they are responsible.