The role of vision in the Corsi block-tapping task: evidence from blind and sighted people.

OBJECTIVE

This study aims at adapting the Corsi Block-Tapping task to measure serial-spatial memory in blind people and at clarifying the role of visual experience in the task.

METHOD

Congenitally blind, adventitiously blind, and blindfolded sighted people were compared on a version of the Corsi board that allowed the haptic perception of block positions (Haptic-Corsi). Participants placed their fingers on the blocks that the experimenter moved upward according to sequences of increasing length. Afterward, participants reproduced the sequences in forward/backward order.

RESULTS

The results showed a significant interaction between groups and forward/backward span: F(2, 58) = 5.74, MSE = .39, p < .01, eta2 = .16. In forward order the memory span was higher in adventitiously blind participants than blindfolded sighted (p < .05) but not congenitally blind participants. In backward order, there were no significant differences.

CONCLUSIONS

The good performance of blind people, especially adventitiously ones, was interpreted as evidence that sequential haptic inputs were organized spatially. The possible cognitive processes underlying the performance were discussed.