Acute Hypoglycemia Impairs Nonverbal Intelligence

Glucoregulation has Greater Impact on Cognitive Performance than Macro-vascular Disease in Men with type 2 Diabetes: Data from the Caerphilly Study

“…Raven's Progressive Matrices (RPM) have been used in several studies showing null findings [32,46,54]. The conflict between the data reported here and studies using the RPM may be a function of population, sample size or test used, as the RPM has a known ceiling effect [55]. Although none of the available studies is sufficiently large to provide certainty, the present study offers data from a larger and more representative sample and brings into question the previously reported null findings.…”

“…Hyperglycaemia has been found to affect memory and complex psychomotor tasks and information processing tasks but not simple psychomotor and simple information processing tasks [28,53]. Abstract reasoning has been shown to deteriorate with hyperglycaemia in several studies [28,53,55]. Deleterious effects of hypoglycaemia have been reported for working memory and speed of information processing [24,27].…”

“…Abstract reasoning was assessed more thoroughly than the other domains providing a closely normal distribution of scores [43] that avoided ceiling effects [55]. Many cognitive tests used in epidemiological studies of diabetes are not sensitive to the upper end of the distribution.…”

Diabetes Associated Cognitive Decline, is there a Role for Exercise?

“…When blood glucose levels reach between 3.6-3.8 mmol/L, the release of counter-regulatory hormones (glucagon, adrenaline) starts. Blood glucose levels of 2.9-3.2 mmol/L provide autonomic and neuroglycopenic symptoms, while cognitive dysfunction starts at blood glucose levels of <2.9 mmol/L [67]. However, during brain imaging studies, hypoglycaemic-associated changes were only seen when plasma glucose was lowered to 2.5 mmol/L [53] or 2.3 mmol/L [68].…”

Moderate hypoglycaemia after learning does not affect memory consolidation and brain activation during recognition in non‐diabetic adults

“…To improve retention, subjects were asked to rate each word or face for its attractiveness, although these data (which are not relevant to the current study) were not analysed. During the next hour subjects completed tests of fluid intelligence (Raven's Advanced Progressive Matrices and the Alice Heim V test), to prevent rehearsal of learned material, and to address a separate research question; results of these have been published elsewhere [25].…”