Final answer:
The amygdala is the recommended structure to study for understanding basic brain mechanisms of emotion and memory, as it plays a primary role in fear response and processes emotional information.
Step-by-step explanation:
For understanding the simplest brain mechanisms underlying emotion and memory, you would recommend that the scientist study the amygdala. Researchers like Joseph LeDoux have demonstrated the primary role of the amygdala in our experience of fear and its association with processing emotional information. When a fear stimulus is processed by the brain, it goes either directly from the thalamus to the amygdala or through the cortex before reaching the amygdala, with the direct path being quicker. This illustrates the amygdala's importance in both quick emotional responses and more detailed processing of emotional stimuli. Moreover, the amygdala has subnuclei that are important in classical conditioning and attaching emotional value to memories, making it a critical component of the brain's emotional circuit.