Which imaging modality shows brain activity by measuring blood flow?

Which imaging modality shows brain activity by measuring blood flow?

• A. Telemedicine
• B. fMRI
• C. Medical Technology
• D. Patient Registration Technology

Answer: (B)

Brain activity is often inferred by how local blood flow changes in response to neural work. Functional MRI uses strong magnetic fields to detect these blood-oxygenation level dependent changes: when a brain area becomes active, blood flow to that area increases, altering the balance of oxyhemoglobin and deoxyhemoglobin and producing a signal that highlights active regions. This makes fMRI a powerful, noninvasive way to map which parts of the brain are working during a task.

Other options don’t fit this mechanism. Telemedicine is about delivering care remotely, not imaging brain activity. Medical technology is a broad category that can include devices, but it isn’t a specific imaging method. Patient registration technology handles administrative aspects like enrollment and scheduling, not physiological imaging.