Katie Pham is a Neuroscience Ph.D. student interested in visual processing and memory research. She was born in Hanoi, Vietnam, and raised in Northern California. Outside of the lab, she enjoys spending time with her cats, watching Family Guy and reading literary fiction.
Published almost five decades ago, Missing Person stands as one of Patrick Modiano’s most refined works. From its opening sentences, the novel establishes a hazy and melancholic tone, enveloping readers in an atmosphere of loss and despair. Adopting a detective novel style, the narrative follows an amnesiac protagonist on a journey back to his roots, seeking to unravel the mysteries of his past. However, the fragments he uncovers do not coalesce into a conclusive whole. Amidst his odyssey, he makes a poignant statement: “In life, it’s not the future that counts, but the past.” Modiano suggests that our identity is shaped by our memories. Accordingly, to solidify our sense of self, we must spend time thinking backward, embracing nostalgia and contemplating the trajectory of our lives.
Modiano would go on to create many more fictional worlds in dreamlike prose, immersing his adult protagonists in deep reflections on crucial events of their past. His dedication to the theme of memory led to his Nobel Prize in Literature in 2014, awarded to him “for the art of memory with which he has evoked the most ungraspable human destinies.”
Memory emerges as a central theme in the works of other Nobel laureates, such as Annie Ernaux and Kazuo Ishiguro. With her 2022 award acknowledging her “acuity in uncovering the roots, estrangements and collective restraints of personal memory,” Ernaux’s narratives delve into her childhood, offering a meticulous dissection of the emotions associated with growing up that is relatable beyond their late 20th-century France social context.
While Modiano and Ernaux’s narrators are dedicated to searching for the truth in their memory, Ishiguro uses unreliable narrators to explore how we examine our lives through the foggy filter of our memory and the stories we tell ourselves, often laden with self-deception. A Pale View of the Hills, for example, is narrated by a British Japanese mother whose daughter has just committed suicide. She reflects on her youth when she was still living in Japan and taking care of a young girl living with her recently widowed mother on an isolated, misty hilltop. Throughout the novel, the girl becomes increasingly disturbed by her isolation while her mother is occupied with finding ways to marry an American man in an attempt to improve their living conditions. At the end of the novel, it is revealed that the narrator has been lying to both the readers and herself, and that the widow’s story was her own.
The essence of Ishiguro’s novels is often encapsulated in their titles and the stories set out to understand the naivete of good intent. His narratives delve into the concluding moments of the narrators’ lives, examining how they reflect on the principles that shaped their journey. The Nobel Prize in Literature was awarded in 2017 to Ishiguro, “who, in novels of great emotional force, has uncovered the abyss beneath our illusory sense of connection with the world.”
The recurrent theme of memory in the works of these laureates raises the question: what makes their content worthy of this award? Since its establishment, the Nobel Prize in Literature has been dedicated to recognizing exceptional works that move in an idealistic direction. What “idealistic” means to the committee has evolved over the years. Yet, authors who manage to capture the most heartfelt version of our humanity are almost always favored. Looking beyond the political and social factors influencing the award’s bestowal, an exploration of the chosen content reveals a consistent focus on the exploration of emotional memory as a fundamental aspect of the human experience. The profound processing of these memories shapes not only momentary emotions and actions but also defines fundamental identity. Thus, being able to skillfully represent these emotional memories in literature is perhaps what made these authors deserving of the award.
Yet, how do our emotions affect the encoding of our memories? As authors of literary fiction probe the impact of these memories in our lives, neuroscientists have provided mechanistic insights underlying their creation, storage and retrieval in our minds. Exploring these mechanisms enhances our understanding of how our emotional memories come to constitute our identity, complementing the pattern of thinking unveiled in the works of these laureates.
Neuroscience research has divided the path our memories take through our brain into four sequential stages: encoding, consolidation, storage and retrieval. Memory encoding begins when various senses (touch, hearing, smell, etc.) in the environment trigger the activity of the brain regions specialized in their processing. These cortical regions send their output to the multisensory parts of the brain, where these signals converge and integrate. These multisensory regions then send information directly to various sites of memory consolidation and storage. When triggered by proper environmental cues, these memories can be retrieved from storage and brought to the forefront of our minds to be used in making decisions.
Not all memories get encoded and retrieved to the same degree, however, and multiple theories have been proposed to explain what type or features of memory get prioritized during each stage of their processing. Interestingly, numerous studies offer compelling evidence regarding the profound impact of emotion on memory processing1,2. Memory encoding and consolidation are notably enhanced when associated with emotionally salient stimuli, defined as those that induce heightened arousal. Meanwhile, emotion’s effect on memory retrieval is more nuanced, with both enhancement and hindrance reported in different cases.
Case studies of patients with damage to a brain region called the amygdala have revealed it to be a key center for emotion processing in the brain. Interestingly, the amygdala is intricately connected with brain regions crucial for processing various memory types, such as working memory in the prefrontal cortex or declarative memory in the medial temporal lobe. Damage to the medial temporal lobe hinders the recall of memories of events or episodes previously experienced, and the interconnected networks between it and the amygdala enable tagging each episodic memory with its associated emotion1.
Determining how each stage of memory processing gets a boost from emotion-evoked activity in the amygdala is an ongoing research topic. Functional brain imaging of healthy subjects during memory encoding reveals heightened amygdala activity in response to emotionally arousing stimuli. This correlated positively with later stimulus recall and recognition — a phenomenon not observed for emotionally neutral stimuli3.
Consolidation of encoded emotional memory has also been revealed to be dependent on the activity of the amygdala. In response to emotionally arousing stimuli, the amygdala triggers the release of stress hormones onto itself as well as sites of memory consolidation and storage to enhance memory processing. By blocking the action of stress hormones in the amygdala of mice, researchers have shown a corresponding loss of emotion-enhanced memory consolidation4. Recently, a study involving recording from the human amygdala and medial temporal lobe immediately following the creation of emotional memory has found specific neural activity patterns that were previously proven to be crucial for the consolidation of spatial memory in rats. It was thought that such neural activity is associated with the replay of the recently encoded memory, which could enable the brain to evaluate its emotional content to strengthen its consolidation process. Indeed, the emotionally salient stimuli that triggered these neural activities were later retrieved at a higher rate by the participants5. Retrieval does not always benefit from being associated with emotionally arousing stimuli, however. Chronic elevations in stress hormones in older high-stress individuals or those with depression and PTSD have been shown to result in declarative memory deficits and subsequent impairment of recall1.
Memory retrieval is also shaped by the emotional context of their recall. While two memories encoded close in time can be linked together through various mechanisms, memory linking is also subjected to emotional binding. Memory engrams with similar emotional valence can selectively interact and integrate even if they do not share close temporal proximity. Such selective interaction between memory engrams biases the memory we can recall toward those with an emotional valence similar to our current emotional state6.
In the climactic moment of Missing Person, Modiano’s protagonist reflects on his futile search, lamenting that only scraps are the fruits of his efforts and perhaps emblematic of what a life amounts to. As he posits that any attempt at recollection will yield only fleeting fragments colored by the context prompting their recall, we are once again reminded of how our emotions act as the volume knob that determines how loudly each memory gets embedded into our minds at every stage of its processing. In light of the considerable cognitive resources dedicated to our emotional memories, it might be reasonable to assert that such memory constitutes the central aspect of our humanity and explains the Nobel Prize’s consistent recognition of literary works centered upon it.
Ultimately, if the thoughts and emotions of these laureates’ narrators are meant to represent humanity at large, then the number of pages spent dwelling on their pasts may suggest a diminished sense of agency in shaping our identities. Yet, it is crucial to distinguish between emphasizing the significance of memories and asserting that they exclusively define us. In the later stages of his career, Ishiguro, in particular, departed from a singular focus on memory to explore the importance of learning to forget and forgive as a means of moving on. In his only post-Nobel Prize novel to date, Klara and the Sun, Ishiguro revisits the mother-and-daughter relationship dynamics previously explored in A Pale View of the Hills. This time, in addition to highlighting the intimacy of this bond, he also emphasizes the necessity of letting go of the memory of one’s daughter when circumstances demand it. Much like Klara seeking guidance from the Sun, the underlying message may be that, regardless of the memories that have shaped the person we are today, even if they were filled with pain and mistakes, there will always be a tomorrow to keep moving toward, with good faith and good intent.
References:
- LaBar, K. S., & Cabeza, R. (2006). “Cognitive neuroscience of emotional memory.” Nature Reviews Neuroscience, 7(1), 54-64.
- Qasim, S. E., Mohan, U. R., Stein, J. M., & Jacobs, J. (2023). “Neuronal activity in the human amygdala and hippocampus enhances emotional memory encoding.” Nature Human Behaviour, 1-11.
- Dolcos, F., LaBar, K. S., & Cabeza, R. (2004). “Interaction between the amygdala and the medial temporal lobe memory system predicts better memory for emotional events.” Neuron, 42(5), 855-863.
- Liang, K. C., Juler, R. & McGaugh, J. L. “Modulating effects of posttraining epinephrine on memory: involvement of the amygdala noradrenergic system.” Brain Res. 368, 125–133 (1986).
- Zhang, H., Skelin, I., Ma, S., Paff, M., Mnatsakanyan, L., Yassa, M. A., ... & Lin, J. J. (2024). “Awake ripples enhance emotional memory encoding in the human brain.” NatureCommunications, 15(1), 215.
- Choucry, A., Nomoto, M., & Inokuchi, K. (2024). “Engram mechanisms of memory linking and identity.” Nature Reviews Neuroscience, 1-18.
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