Throwback Thoughts: Unpacking the Neuroscience of Nostalgia
Picture from the I Spy Series, a staple of our childhoods. (I never found the man on the bike)
What is Nostalgia?
Not everything we remember is pleasant. Whether it is getting rejected by the prettiest girl in your class that one time during 7th grade recess, or ripping a fat one in the middle of a packed college library (no particular reason why those two come to mind…), we all have uncomfortable memories that we would like to forget. If all you have are bad memories, reading this article should be the least of your concerns. But chances are, we all have some distant event in our lives that brings a tremendous sense of ease and calmness whenever it crawls into our consciousness. This feeling of nostalgia can have many downstream effects that drastically alter our attitude and physical sensations. In this article, we will discuss the psychological effects of nostalgia through a neuroscience lens and highlight the complex emotional response we have towards pleasant memories.
Nostalgia is a complex feeling of multiple emotions; it’s not as cut and dry as it seems. Taken generally, nostalgia is a predominantly positive feeling that is centered around memories of your past, which are called autobiographical memories. Feelings of nostalgia often provide an escape and allow you to revisit important memories of your past. But what does nostalgia look like in the brain?
Neural Circuits of Nostalgia
Nostalgia can be seen as having four key components; self-reflection processing, autobiographical memories, emotional regulation, and reward, with each core component having many different brain regions associated with it. Researchers have postulated that these four elements are what lead to feelings of nostalgia in our everyday lives. These regions are scattered throughout our brains and work together to produce this feeling within. Some of these regions include the medial and ventromedial prefrontal cortex (MPFC and VMPFC, respectively), the anterior cingulate cortex (ACC), the hippocampus (HPC), the striatum, and the substantia nigra/ventral tegmental area (SN/VTA). All of these regions were more strongly activated in nostalgic conditions compared to control ones, and can be seen in this diagram. (Yang et al., 2022)
Looking at some of these regions in-depth, the MPFC is located right in the front of our brains and can be perceived as one of the hubs of nostalgia, as it is shown to play important roles in tasks that involve self-reflection. Additionally, this region has a role in three out of the four core components of nostalgia, being vital for autobiographical memory and emotional regulation as well (Yang et al., 2022). Another important region to talk about briefly is the hippocampus, which is a seahorse-like structure deep in our brain that plays key roles in memory. Given the nature of nostalgia, it’s no surprise that a brain region so deeply intertwined with memory is involved. Regions such as the Striatum, SN, and VTA are key components of our reward circuitry and a target of many of the addictive psychoactive drugs that are prevalent in society. The main neurotransmitter released by these regions is dopamine, which is crucial for reward processing and feelings of pleasure. Feelings of nostalgia act on these regions to produce the positive sensations of our past that we all know and love.
Individual Studies Concerning Nostalgia
The research on nostalgia is sparse, but individual studies do exist that help to elucidate some cognitive mechanisms of this feeling. In one study, participants underwent fMRI (functional magnetic resonance imaging) sessions, which allows researchers to measure changes in blood flow in specific regions of the brain. An increase in blood flow to certain areas indicates that these areas are more active during a given task. Participants were presented with nostalgic images, such as an elementary school bulletin board, or control images, like a bulletin board at a train station, and their patterns of brain activation were measured. Researchers found significant hippocampus and reward-related area activity between the nostalgic vs. control picture groups, and that these regions were co-activated during nostalgic experiences elicited by visual stimuli. This reinforces the framework that we mentioned in the previous paragraph: these regions all work together! (Oba et al., 2016)
To complement this, there is evidence that nostalgic sensations can have analgesic (pain inhibition) effects. One study exposed participants to pictures of scenes/objects from their childhood and immediately exposed them to painful stimuli of different intensities. Not only did the “nostalgic participants,” experience lower overall pain relative to controls, but fMRI imaging indicated that they also had lower activation in pain-sensitive areas of the brain. While it is challenging to directly point to a specific network that causes this effect, the thalamus (a key part of the brain that receives and transmits pain information) plays a massive role. Nostalgia likely affects our top-down processing of nociceptive (pain) stimuli, ultimately resulting in a blunted sensation. (Yang et al., 2022)
Final Thoughts
Nostalgia is one of those feelings that you never want to go away. It sucks that time moves on, but those positive memories and the feelings associated with them will always be there. According to the great Ferris Bueler, “Life moves pretty fast. If you don’t stop and look around once in a while you could miss it.” Sometimes, all you need is that little feeling of nostalgia to help you take a break to slow down and enjoy what’s around you.
Sources:
Oba, K., Noriuchi, M., Atomi, T., Moriguchi, Y., & Kikuchi, Y. (2016). Memory and reward systems coproduce 'nostalgic' experiences in the brain. Social cognitive and affective neuroscience, 11(7), 1069–1077. https://doi.org/10.1093/scan/nsv073
Yang, Z., Izuma, K., & Cai, H. (2023). Nostalgia in the brain. Current Opinion in Psychology, 49, 101523. https://doi.org/10.1016/j.copsyc.2022.101523
Yang, Z., Wildschut, T., Izuma, K., Gu, R., Luo, Y. L. L., Cai, H., & Sedikides, C. (2022). Patterns of brain activity associated with nostalgia: a social-cognitive neuroscience perspective. Social cognitive and affective neuroscience, 17(12), 1131–1144. https://doi.org/10.1093/scan/nsac036
