Roger Dixon and his colleagues at Canada’s University of Alberta have found that healthy people significantly outperformed patients with diabetes on tasks involving higher thought processes.
One thought process that has shown a slowdown is the speed of analysing sentences — tested by asking participants to read 50 sentences and stating whether each sentence was plausible or nonsensical. Example of such sentences: “the tree fell to the ground with a loud crash”, or “the pig gave birth to a litter of kittens”. Healthy people were found to be significantly faster than patients with diabetes.
Sources: The study was published in the journal Neuropsychology. dated:6th.Jan.’09