A patient has a CT scan and a PET scan of the same brain region. The CT scan shows a small blood clot. During a listening task, the PET scan shows similar activity to that in a healthy comparison group.
Which conclusion is justified?
the CT scan shows a structural change, but the PET result gives no evidence of lower activity during this listening task
the results suggest this region causes listening because its activity was measured during the listening task
the CT result suggests the clot is affecting listening because CT records activity during the task
the PET result suggests the clot is no longer present because activity matches the healthy group
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.