A group of healthy volunteers takes part in a study of the functions of different brain regions. Each volunteer has a CT scan. PET scans are then carried out while the volunteer is resting and while completing two tasks.
| task | tracer uptake in a region at the top and front of the brain | tracer uptake in a region at the back and base of the brain |
|---|---|---|
| solving an unfamiliar word puzzle | higher than when resting | the same as when resting |
| making a sequence of accurately aimed finger movements | higher than when resting | higher than when resting |
Explain how the researchers can use the CT and PET evidence to investigate the roles of these brain regions, and why scanning is more suitable than investigating the brain directly.
111 exam-style questions on Edexcel GCSE Biology 2.3 The nervous system and brain, covering 2.3.1 Structures and functions of the brain, 2.3.2 Imaging brain function with scanning, 2.3.3 Limitations in treating nervous system damage, 2.3.4 Neurones and impulse transmission, and 2.3.5 Structure and function of a reflex arc. Each one has a worked solution and a mark scheme showing where the marks go.