It has been really bothering me that our friend Clive, who suffers from retrograde and anterograde amnesia, can remember how to sight-read a piano piece, but cannot recall what chicken tastes like so I decided to explore what happens to the brain when listening/playing/sight-reading music.
Before the virus, Clive was a musicologist, conductor, singer, and pianist. Although he cannot recall his past experiences, he is able to sit down at the piano and play presumably because his procedural memory is still intact (he cannot remember playing a piece minutes earlier since he does not have episodic memory). It appears as though the main brain area that the virus affected was the hippocampus, which is logical due to its significance in consolidating episodic short-term to long-term memory.
I found an article that used fMRIs in healthy, professional pianists when sight-reading. Various types of sight-reading were tested (notation, verbal cues (do re mi fa so), and number notation) to investigate if different methods of encoding altered the brain areas required. Researchers did find that different brain areas were used for the different stimuli (researchers presented controls with similar stimulation and had them press buttons so that they could subtract the brain areas required for movement and visual stimuli). In the video, Clive was using musical notation, which requires more activation in the parietal lobe (specifically the superior parietal gyrus, the angular gyrus, and the supramarginal gyrus). Other important areas include the right occipitotemporal gyrus, the left sensorimotor cortex, the right cerebellum, and the right occipital cortex. However, the multiple was of sight-reading can occur at the same time, especially when someone has used these skills for a while.
I also learned some interesting/slightly personal facts about Clive in some of my research. Clive was 46 years old when the hippocampal damage occurred, his wife Deborah 27! He does recall that he has children, but cannot remember their names or any information about them. He was only married to his (second/current) wife for six months before the virus (though they met six years before), yet he recognizes and greets her with great enthusiasm every time he sees her. Often times, retrograde amnesia is graded in the opposite fashion: the older memories are most likely to be retained than the newer memories since the neural pathways are older and stronger. How come the only person that Clive can recognize is someone he met so relatively recently?