The roots of the economic crisis were the topic of Thursday’s hearing of the Senate Banking, Housing and Urban Affairs Committee. Sen. Chris Dodd, the committee’s chair, said the underlying issues of the crisis has yet to be dealt with. Witnesses before the committee included Sheila C. Blair, chairman of the Federal Deposit Insurance Corporation, and Neel Kashkari, the interim assistant secretary for financial stability at the U.S. Department of the Treasury.