An introductory text reads:
Whether with lab rats or case studies, psychologists have spent decades tracking the location of memory in the brain. Their findings point to a complex system involving multiple brain regions. Memory is formed, processed, and stored throughout the brain, and different types of memory have different paths. So it helps to know your way around the brain’s structures. Remembering the amygdala’s role in processing basic emotion, for instance, can help you understand its role in processing the emotional content of memories.
An illustration shows an external view of a brain. The labeled parts are as follows: The cortex covering the front part of the frontal lobe is labeled prefrontal cortex, text reads: working memory essential for retrieval. The outermost layer at the top of the cerebrum is labeled cerebral cortex. Text reads: memory storage distributed throughout. The folding in the superior temporal gyrus of the temporal lobe and extends into the lateral sulcus and the transverse temporal gyri is labeled auditory cortex. Text reads: mostly hidden from view, auditory memory storage. The region below the frontal lobe and parietal lobe is labeled temporal lobe. Text reads: spatial memory storage. The region in the occipital lobe is labeled visual cortex. Text reads: visual memory storage. A small curvy region in the medial temporal lobe below the basal ganglia is labeled hippocampus. Text reads: memory consolidation and explicit memory formation. An almond-shaped structure at the end of basal ganglia is labeled amygdala. Text reads: implicit memory formation, emotional memory formation. A tightly folded and crumpled part below the temporal lobe is labeled cerebellum. Text reads: implicit memory formation.
A panel titled, learning from H M reads as follows: Henry Molaison, or "H M" (1926 to 2008), may be the "best known single patient in the history of neuroscience" (Squire, 2009, para 1). Following the surgical removal of his hippocampus, H M lost the ability to form new explicit memories, but he could still create certain types of implicit memories. This suggests that the hippocampus plays a key role in the creation of explicit- but not necessarily implicit- memories.
A photo shows a digitized section of the brain of Henry Molaison. Text reads: After his death, H M’s brain was cut into over 2,000 slices that were preserved and digitized for research.
A panel titled, Lashley’s Quest reads as follows: Through his experiments with rats, Karl Lashley tried to find the physical location of memories in the brain. He would train the rats to navigate mazes, make slices in various parts of their cortices, and then observe how their memories of the mazes were affected. In many cases, these slices had minimal impact on the rats' ability to navigate the mazes. With the help of modern technologies, researchers have discovered that memory activities occur in many areas of the brain (Shen, 2018, March 14). In a process called memory consolidation, which is thought to occur in the hippocampus and cortex, information is moved into long-term storage (Genzel et al, 2017).
An image shows sketches of lesions made on each rat. Text reads: Lashley kept a careful record of the sizes and locations of lesions made in each rat as part of his experiments.