Which imaging technique is associated with the potential for early detection of Alzheimer's disease in the material?

• A. EEG
• B. MRI
• C. PET
• D. fMRI

Answer: (D)

Early detection in this context is about spotting changes in brain function before there are visible structural changes. fMRI measures the BOLD signal, which tracks how brain regions activate and how their communication patterns shift. In the earliest stages of Alzheimer’s, disruptions often appear in memory-related networks, like the default mode network and hippocampal connectivity, and these functional changes can show up on fMRI even when MRI looks normal. That makes fMRI the imaging modality linked to the idea of catching the disease early in the material. While EEG, structural MRI, and PET have important uses—EEG for timing, MRI for anatomy, and PET for metabolism or amyloid biology—fMRI uniquely highlights functional network changes that can precede structural damage.