In Jourdain’s book, Music, the Brain, and Ecstasy (1997), mental illnesses and the description of the hippocampus interested me most. Jourdain describes in the Chapter 6 (Composition), that, “psychologists have divined symptoms of manic-depressive illness in Berlioz, Bruckner, Dowland, Elgar, Gesualdo, Glinka, Handel, Holst, Ives, de Lasses, Mahler, Mussorgsky, Rachmaninoff, Rossini, Schumann, Tchaikovsky, and Wolf.” (p. 172) Unfortunately, he doesn’t go into detail of how these composers were discovered to have manic-depression and where specifically in the brain, it affects. Pages prior, Jourdain does mention that, “Neuroscientists have never found a place in the brain where discrete memories are stored.” (p. 164) The assumption then, is that mental illnesses do not affect one single area of the brain; similar to how memories (highly influenced also, in mental illnesses,) are stored in various parts of the brain.
Jourdain mentions briefly, of mental illnesses in his book. There is no elaboration of the different types of mental illnesses the composers experienced, specifically, other than the fact that the composers listed above, experienced manic-depressive illnesses. Within one page, Jourdain brushes through depression. On the other hand, Jourdain also mentions the hippocampus briefly, in his book. The hippocampus in the brain is crucial to long-term memory, while the frontal lobes juggle the content of short-term memory. He mentions that, “Removing the hippocampus renders a person unable to form new long-term memories. But that person will still be able to ponder things in the short-term memory.” (p. 164)
My interest is in post-traumatic stress disorder (PTSD) and the effects the brain has on it. Unfortunately, few research in music, the brain, and PTSD has been discovered, resulting with a lack of formal understanding of how scientifically, music therapy has improved the brain of a patient with PTSD. In this short essay, I would like to explore the questions: How does music affect the hippocampus? Also, how does the hippocampus function in patients with PTSD?
Shin, Rauch, and Pitman’s research called, “Amygdala, Medial Prefrontal Cortex, and Hippocampal Function in PTSD” (2006), explains that the hippocampus is involved in explicit memory processes and in the encoding of context during fear conditioning (p. 68). Not only is the hippocampus affected in PTSD, but it appears to interact with the amygdala during the encoding of emotional memories. This is a process highly relevant to the study of trauma and PTSD. This disorder has been associated with memory impairment as well as reduced hippocampal volumes and abnormal hippocampal function. On the other hand, a research conducted by Bonne et. al., in their research, “Longitudinal MRI Study of Hippocampal Volume in Trauma Survivors with PTSD” (2001) concludes that, smaller hippocampal volume is not a necessary risk factor for developing PTSD and does not occur within six months of expressing the disorder. This brain abnormality might occur in individuals with chronic or complicated PTSD. One of the critiques of this research may be of the small amount of subjects used (only thirty-seven survivors of traumatic events were examined).
What I found interesting from Shin, Rauch, and Pitman’s (2006) research is the claim that, hippocampal volumes have been inversely associated with verbal memory deficits, depression severity, and PTSD symptom severity. Instead, greater PTSD symptom severity has been associated with smaller hippocampal volumes and elevated hippocampal/parahippocampal blood flow (p. 72). These research findings confuse me though, because they explain the hippocampus as a whole, and not of respective left and right hippocampi.
With Watanabe, Yagishita, and Kikyo’s research, “Memory of music: Roles of right hippocampus and left inferior frontal gyrus” (2007), they express that the role of the bilateral hippocampi is commonly associated with accurate memory outcome. Previous positron emission tomography (PET) studies of memory using words and pictures found positive correlations between retrieval performance and regional cerebral blood flow in the left hippocampus. Their results suggest that the bilateral regions have different memory retrieval targets: words for the left and music for the right (p. 490). Because Watanabe, Yagishita, and Kikyo discovers that the right hippocampus, left IFG, bilateral lateral temporal regions and left precuneus were identified as the regions of retrieval success for music memory, they are able to demonstrate that the right hippocampus responds to the retrieval success more strongly than the left (and the left IFG responses more strongly than the right) (p. 487). Since the right hippocampus showed significant response in the music retrieval success, it proves the ongoing declaration made by scientists for years, that the right side of the brain is more “artsy.” Jourdain (1997) himself, claims that the “right hemisphere excels in making sense of melodies” (p. 83) while the “left hemisphere is prominent in analyzing the rhythmic patterns found in melodies.” (p. 84)
These researches unfortunately do not link together, the complete aspects and functions of the hippocampus, but continues to reveal the complexity of the hippocampi in the brain. The hippocampus may affect mental illnesses and the memory retrieval of musicians, and yet, the specifics of how the hippocampus is affect remains unknown. On the other hand, Herderner et. al. discovers functional changes of the adult hippocampus in humans related to musical training. In their journal, “Musical Training Induces Functional Plasticity In Human Hippocampus” (2010), they found a correlation of hippocampal sensitivity to temporal novelty with musical abilities. Based on their imaging and behavioral data, the changes in hippocampal activity in musicians represent tuning of aural skills related to time interval perception. In addition, Herderner et. al. finds evidence showing that lesions of the left hippocampus in humans impair performance related to time interval discrimination, supporting the behavioural relevance of the left hippocampus for temporal novelty detection in the acoustic modality.
The music-related research of the hippocampus overall, remains constant of Jourdain’s claims almost two decades ago. The possible change since will be the discovery of hippocampus activity within PTSD patients. This is of value to me due to my interest in music with those in conflict countries. In a war-torn country such as Afghanistan, many people are struck with depression and PTSD (locals and foreigners alike). Afghans have expressed to me that music heals their heart. They continue to produce music (whether allowed or not), because it brings them comfort. Music continues to hold nationalistic pride as they sing folk tunes, and increasingly popular with young Afghans’ interest in western pop music. Music is their healing. With that said, the continuous need for scientific research in music and the brain with victims of post-traumatic stress disorders is needed in order to form solid information for music therapists.
Sources:
Bonne, O., Brandes, D., Gilboa, A., Moshe Gomori, J., Shenton, Martha E., Pitman, Roger K., and Shalev, Arieh Y. “Longitudinal MRI Study of Hippocampal Volume in Trauma Survivors With PTSD." American Journal of Psychiatry (2001): 1248-251.
Groussard, Mathilde, Renaud La Joie, Géraldine Rauchs, Brigitte Landeau, Gaël Chételat, Fausto Viader, Béatrice Desgranges, Francis Eustache, Hervé Platel, and André Aleman. "When Music And Long-Term Memory Interact: Effects Of Musical Expertise On Functional And Structural Plasticity In The Hippocampus." PLoS ONE (2010): E13225.
Herdener, M., F. Esposito, F. Di Salle, C. Boller, C. C. Hilti, B. Habermeyer, K. Scheffler, S. Wetzel, E. Seifritz, and K. Cattapan-Ludewig. "Musical Training Induces Functional Plasticity In Human Hippocampus." Journal of Neuroscience (2010): 1377-384.
Jourdain, Robert. Music, the Brain, and Ecstasy: How Music Captures Our Imagination. New York: W. Morrow, 1997.
Shin, L. M., Rauch, S. L. and Pitman, R. K. "Amygdala, Medial Prefrontal Cortex, And Hippocampal Function In PTSD." Annals of the New York Academy of Sciences (2006): 67-79.
Watanabe, Takamitsu, Sho Yagishita, and Hideyuki Kikyo. "Memory of Music: Roles of Right Hippocampus and Left Inferior Frontal Gyrus." NeuroImage (2008): 483-91
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