Brain Imaging

Brain imaging techniques split into static (structure) and functional (activity).

Static imaging:

• CAT scan: X-rays
• MRI: magnetic fields, better detail, no radiation

Functional imaging:

• ERP: electrical brain activity over time, very good temporal resolution
• PET and fMRI: metabolic / blood-flow measures, better spatial resolution
• BOLD signal: blood oxygenation level dependent signal in fMRI; tracks blood-flow changes linked to neural activity

Donders' subtractive logic

To isolate a cognitive process, subtract a simpler control task from a more complex task. Whatever’s left in the difference is (hopefully) just the process you care about. Used to design clean fMRI experiments.