FRANKFURT — Christine Lagarde is one of the most recognizable people on the world stage, but as president of the European Central Bank, a job she began six weeks ago, she has been a cipher.

That began to change Thursday as Ms. Lagarde held her first news conference as leader of an institution that has often determined Europe’s economic fate. She promised to consider more opinions in making policy, and she reported signs that the eurozone’s economic slowdown was abating.

The event followed a meeting of the bank’s Governing Council, which made no changes to monetary policy.

Analysts and investors were listening intently during Ms. Lagarde’s session with reporters for clues about her opinions on questions such as whether the central bank’s fire hose of economic stimulus has begun to do more harm than good.