In various embodiments, a catheter comprising an expandable electrode assembly or basket is provided. In specific embodiments, the basket is particularly useful for mapping electrical activity at one or more locations within the heart. The basket can comprise a plurality of bendable or deflectable arms. At least one of the arms may have varied flexibility over its length in the form of one or more discontinuities of stiffness or flexibility at an elbow region or other variances in flexibility over the arm's length. Such variance in flexibility may allow the arm to assume a different bent configuration or respond to external factors more positively than possible with an arm having a static or near static flexibility or stiffness over its length.