Forward and backward digit span as a function of articulation rate. TaoDuoduo DengRui JiangYe J. Galvin IIIJohn FuQian-Jie ChenBing 2014 <p>The left panel shows CI data and the right panel shows NH data. The black circles show forward digit span data and the red circles show backward digit data. R squared values and <i>p</i> values are shown in the right of each panel. FDS  =  forward digit span; BDS  =  backward digit span.</p>