Appraising the brain's energy budget
Marcus Raichle and Debra Gusnard write a short commentary on how the brain spends its energy. They note that the brain is a small share of body weight yet accounts for a large share of the oxygen and calories the body consumes, and that this rate of metabolism stays remarkably constant despite varying mental and motor activity. They set the cost of the brain's ongoing activity against the small, transient changes in local blood flow that imaging studies of cognitive tasks usually record, and argue that cognitive neuroscience has focused almost exclusively on those transient changes while neglecting the far larger amount of ongoing functional activity. This page cites the commentary for the brain's energy share and for the small size of task-related changes.
Marcus Raichle and Debra Gusnard write a short commentary on how the brain spends its energy. They note that the brain is a small share of body weight yet accounts for a large share of the oxygen and calories the body consumes, and that this rate of metabolism stays remarkably constant despite varying mental and motor activity. They set the cost of the brain's ongoing activity against the small, transient changes in local blood flow that imaging studies of cognitive tasks usually record, and argue that cognitive neuroscience has focused almost exclusively on those transient changes while neglecting the far larger amount of ongoing functional activity. This page cites the commentary for the brain's energy share and for the small size of task-related changes.
Written from the full text on PubMed Central, read 2026-10-23 (the commentary has no abstract).
What our sources record
Recorded when this source was checked, figures included, with page references and quotation marks removed.
Raichle, M. E., & Gusnard, D. A. (2002). Appraising the brain's energy budget. Proceedings of the National Academy of Sciences, 99(16), 10237-10239. doi:10.1073/pnas.172399499