Final answer:
Karl Lashley sought to locate the engram or memory trace, which led to the discovery that memories are not stored in a single part of the brain but are distributed throughout it, involving the amygdala, hippocampus, cerebellum, and prefrontal cortex.
Step-by-step explanation:
Karl Lashley conducted explorations of the brain trying to locate the engram or memory trace. In searching for this, he trained rats to navigate a maze and then created lesions within their cerebral cortex to see if it would affect their memory of the maze. Lashley did not find a conclusive location for the engram, demonstrating that memories were not stored in one specific area but were distributed throughout the brain. This concept was known as the equipotentiality hypothesis. His work laid the foundation for future research into memory, and now we know that several regions of the brain, including the amygdala, hippocampus, cerebellum, and prefrontal cortex, play crucial roles in processing and storing different types of memories. The hippocampus, for instance, is key in encoding new memories, while the amygdala helps determine what memories are stored, particularly those associated with strong emotional responses. Lashley's research, although did not confirm the engram, spurred further progress in memory research, leading to the identification of specific neural circuits and regions correlated with memory.