EEG topography during insulin-induced hypoglycemia in patients with insulin-dependent diabetes mellitus

Eur Neurol. 1996;36(5):303-9. doi: 10.1159/000117277.


A group of young patients with insulin-dependent diabetes mellitus (n = 14; 8 men, 6 women; 33.1 +/- 8.9 years) were examined by topographic EEG mapping under normoglycemic and hypoglycemic conditions (glucose levels after intravenous insulin injection down to 32.6 +/- 7.6 mg/dl). From the clinical aspect, 7 of them had a good and 7 had a poor awareness of hypoglycemia. During hypoglycemia, a decrease in alpha activity (p < 0.05), an increase in delta (p < 0.05), and especially in theta activity (p < 0.05) were found. The most sensitive parameter was the alpha/theta ratio. In the range of slight hypoglycemia (50-60 mg/dl) the increase in delta and theta activity showed a topographic maximum in lateral frontal regions. During deep hypoglycemia there was a topographic maximum of slow frequencies in posterior parts of the brain (centrotemporal to parieto-occipital regions). The differences between the group with good and with poor awareness of hypoglycemia were most pronounced during slight hypoglycemia in C3, C4, and Pz (p < 0.05). At lower glucose levels group distinction was no longer possible. These EEG changes correspond to a temporary organic brain syndrome.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Awareness
  • Brain Mapping
  • Diabetes Mellitus, Type 1 / blood*
  • Electroencephalography*
  • Female
  • Humans
  • Hypoglycemia / chemically induced*
  • Hypoglycemia / physiopathology*
  • Hypoglycemia / psychology
  • Insulin*
  • Male
  • Self Concept


  • Insulin