Blood glucose discrimination training: the role of internal and external cues

The effects of observing internal and external events on blood glucose (BG) discrimination were assessed in eight patients with type 1 diabetes using an intrasubject design. During baseline condition, participants estimated their BG, then measured and recorded it (feedback-only procedure) three times a day. Participants were then divided randomly into two groups. Both were submitted to internal cue (IC) and external cue (EC) training conditions in a balanced order, and then both cues were presented together in combined cues (CC) training conditions. Under IC, participants observed and recorded their symptoms before estimating BG. Under EC, they observed and recorded environmental events prior to BG estimation. In CC conditions, participants paid attention to both internal and external cues before the estimate-feedback routine. BG estimation accuracy improved after either IC or EC conditions. When the two types of cues were combined, only two participants improved their BG estimation accuracy. The remainder did not, probably because they had already attained high accuracy levels (ceiling effect).