Effects of hypoglycemia on cognition were studied using event-related brain-potential (ERP) measures and reaction times at the Otto-von-Guericke University, Magdeburg, Germany. ERP measures of selective attention, response choice and reaction time were delayed during hypoglycemia compared to baseline performance. After restoration of euglycemia, total-error frequencies were still higher than at baseline and recovery of the quality of task performance was delayed. Hypoglycemia impairs both the stimulus and the motor-response selection. Large negative shifts in cortical potentials were distributed over frontal areas during hypoglycemia, suggesting that the frontal cortex is involved in the control of attention and stimulus selection. [1]

COMMENT. Hypoglycemia has an adverse effect on attentional behavior by increasing reaction times and error frequencies. After restoration of normal blood sugar levels there is a delay in recovery of quality of task performance. The frontal cortex is more highly activated during acute hypoglycemia as a compensatory mechanism for the reduced energy supply to the brain. Frontal location brain mechanisms, important in control of attention, are particularly affected by the impaired energy supply associated with hypoglycemia.