TY - JOUR
T1 - Changes of cognition and regional cerebral activity during acute hypoglycemia in normal subjects: A H2 15O positron emission tomographic study
AU - Bie Olsen, Lise Grimmeshave
AU - Bie-Olsen, Lise G
AU - Kjaer, Troels W
AU - Pedersen-Bjergaard, Ulrik
AU - Lonsdale, Markus N
AU - Holst, Jens Juul
AU - Law, Ian
AU - Thorsteinsson, Birger
N1 - Keywords: Adult; Brain Mapping; Cerebral Cortex; Cerebrovascular Circulation; Cognition; Cognition Disorders; Functional Laterality; Glucose; Humans; Hypoglycemia; Insulin; Male; Mental Processes; Neuropsychological Tests; Oxygen Radioisotopes; Perception; Positron-Emission Tomography; Vision, Low; Visual Pathways; Young Adult
PY - 2009
Y1 - 2009
N2 - Blurred vision and cognitive difficulties are prominent symptoms during acute insulin-induced hypoglycemia. Our hypothesis was that changes in cerebral activity reflect these symptoms. Positron emission tomography (PET) with oxygen-15-labelled water was used to measure relative changes in regional cerebral blood flow (rCBF) as a marker of cerebral activity. Hypoglycemia was induced by intravenous insulin infusion in 19 healthy men performing two different cognitive tasks of varying complexity. The hypoglycemic stimulus [plasma glucose 2.2 mmol/liter (0.4)] produced a significant hormonal counterregulatory response. During the low cognitive load, rCBF decreased in response to hypoglycemia in a large bilateral area in the posterior part of the temporal lobe, and rCBF increased bilaterally in the anterior cingulate gyrus, the right frontal gyrus, the fusiform gyrus, thalamus, and the left inferior part of the frontal gyrus. During the high cognitive load, rCBF decreased bilaterally in a large region in the posterior part of the temporal gyrus and increased in the left and right anterior cingulate gyrus, left and right frontal gyrus, right parahippocampal and lingual gyrus, and left superior temporal gyrus. Visual impairment during hypoglycemia was associated with deactivation in the ventral visual stream. The anterior cingulate gyrus was activated during hypoglycemia in a load-dependent manner. Areas on the frontal convexity were differentially activated in response to the cognitive load during hypoglycemia. Our findings suggest that hypoglycemia induces changes in sensory processing in a cognition-independent manner, whereas activation of areas of higher order functions is influenced by cognitive load as well as hypoglycemia.
AB - Blurred vision and cognitive difficulties are prominent symptoms during acute insulin-induced hypoglycemia. Our hypothesis was that changes in cerebral activity reflect these symptoms. Positron emission tomography (PET) with oxygen-15-labelled water was used to measure relative changes in regional cerebral blood flow (rCBF) as a marker of cerebral activity. Hypoglycemia was induced by intravenous insulin infusion in 19 healthy men performing two different cognitive tasks of varying complexity. The hypoglycemic stimulus [plasma glucose 2.2 mmol/liter (0.4)] produced a significant hormonal counterregulatory response. During the low cognitive load, rCBF decreased in response to hypoglycemia in a large bilateral area in the posterior part of the temporal lobe, and rCBF increased bilaterally in the anterior cingulate gyrus, the right frontal gyrus, the fusiform gyrus, thalamus, and the left inferior part of the frontal gyrus. During the high cognitive load, rCBF decreased bilaterally in a large region in the posterior part of the temporal gyrus and increased in the left and right anterior cingulate gyrus, left and right frontal gyrus, right parahippocampal and lingual gyrus, and left superior temporal gyrus. Visual impairment during hypoglycemia was associated with deactivation in the ventral visual stream. The anterior cingulate gyrus was activated during hypoglycemia in a load-dependent manner. Areas on the frontal convexity were differentially activated in response to the cognitive load during hypoglycemia. Our findings suggest that hypoglycemia induces changes in sensory processing in a cognition-independent manner, whereas activation of areas of higher order functions is influenced by cognitive load as well as hypoglycemia.
U2 - 10.1002/jnr.22002
DO - 10.1002/jnr.22002
M3 - Journal article
C2 - 19170163
SN - 0360-4012
VL - 87
SP - 1922
EP - 1928
JO - Journal of Neuroscience Research
JF - Journal of Neuroscience Research
IS - 8
ER -