Final answer:
Scientists use techniques like fMRI to observe the whole brain in action and measure activity in response to specific conditions or events.
Step-by-step explanation:
Scientists also have the ability to observe the whole brain in action - rather than relying solely on autopsies or indirect methods. One example of a technique used to observe brain activity is functional magnetic resonance imaging (fMRI). This technique measures changes in brain tissue in response to specific conditions or events, generating a three-dimensional map of the most active areas. By having the subject perform a task, such as looking at a photograph and recognizing someone, activity all over the brain can be measured.