“What surprised us most was not that the neurons were taking up less glucose – this is to be expected due to the differences in neuron sizes,” says Kaja von Eugen of Ruhr University Bochum, Germany. “But the magnitude of the difference is so great that the size difference cannot be the only factor contributing to it. It means there must be something additionally different in the birds’ brains that enables them to maintain such low costs.”
Von Eugen and colleagues sought to determine the energy “budget” of bird neurons based on studies in pigeons. They used imaging techniques that allowed them to assess glucose metabolism in birds. They also used modeling techniques to calculate brain metabolic rate and glucose uptake.
Their research showed that the pigeon brain consumes very low amounts of glucose (27.29 ± 1.57 µmol glucose per 100 g per minute) while the animal is awake. Thus, neurons in bird brains consume, on average, three times less glucose than neurons in mammalian brains. In other words, their neurons are cheaper for unknown reasons.
Source: Ferra
