The study involving 85 sixth through ninth graders tested J. Torgesen's hypothesis that learning disabled (LD) children's performance deficits occur as a result of a "passive" approach to tasks rather than a cognitive processing deficit as assumed by other existing definitions. LD students were matched with nonhandicapped peers and administered discrimination learning problems. During Session I, Ss received no monetary reinforcement for correct responses, while in Session II, the experimental group received reinforcement and response cost in the form of tokens contingent on correct and incorrect answers. Torgesen's hypothesis was not supported. Processing deficits were identified in the LD students' ability to code, recode, and recall information compared to regular students. LD Ss were also deficient in benefiting from explicit feedback. All Ss in the control group demonstrated overall superior performance to those in the reinforcement, response cost condition. Figures of experimental materials and tables with statistical data are included. (Author/SB)