Human memory is a complex process that determines what information we retain and what we forget. While neurons are known to play a crucial role in the formation of memories, a recent study has revealed that glial cells, specifically astrocytes, also play a critical role in this process. Astrocytes, which surround neurons, are primarily known for their supportive function, but have now been found to have a direct influence on which memories remain and which fade over time.
This finding challenges previous theories about memory consolidation, suggesting that short- and long-term memories are not formed sequentially, but can develop simultaneously. Through techniques such as optogenetics, researchers have been able to manipulate these astrocytes in animal models, demonstrating how their chemical state can determine the persistence or forgetting of memories, especially those that are emotionally charged.
Memory is one of the most fascinating processes of the brain and human cognition, allowing us to store, retrieve and learn from past experiences. Broadly speaking, memories can be divided into two types: short-term and long-term. The former are temporary and last for a few seconds or minutes, while long-term memories have the capacity to last for years, if not a lifetime.
The process of memory consolidation begins when a stimulus or experience is perceived and transmitted through neurons, the cells responsible for communication in the brain. Initially, this information is stored in the hippocampus, a key region for recent memory. However, For a memory to become something lasting, it must go through a consolidation processin which information is restructured and stored in other areas of the brain, such as the cerebral cortex.
In this process, not only neurons are involved. Other brain cells, such as astrocytes, play an essential role in maintaining the neuronal environment. Although they are often considered a simple “support” for neurons, recent research suggests that astrocytes have a direct influence on the formation and consolidation of emotional memories.
What are astrocytes and what is their function?
Astrocytes are a type of glial cell, which are non-neuronal cells in the brain, but play crucial functions for the proper functioning of the nervous system. Although they have traditionally been considered a support for neurons, providing nutrients and helping in tissue repair, more recent research has revealed that their role is much more complex and active in brain processes.
One of the most relevant functions of astrocytes is to regulate the environment of neurons. They maintain the balance of ions, eliminate metabolic waste and participate in the formation of the blood-brain barrier, which protects the brain from external agents. However, its involvement in memory is even more fascinating. Astrocytes influence communication between neurons, modulating the synapses (the connection points between them), which directly affects brain plasticity, an essential process for the formation of new memories.
Recently, it has been discovered that astrocytes also play a determining role in the storage and preservation of emotional memories. In fact, its chemical state, such as its acidity or alkalinity, can influence whether a memory is maintained in long-term memory or quickly forgotten. This opens up new possibilities for understanding how memories are formed and how they can be manipulated.
The experiment and its findings
A recent study by researchers at Tohoku University has revealed surprising discoveries about the role of astrocytes in the persistence of memories, especially emotional ones. The researchers used an innovative technique called optogenetics, which allows the control of specific cells using light. This technique was used to manipulate astrocytes in the brains of mice and study how their chemical changes affect memory, in particular emotional memory related to fear.
In this experiment, scientists induced fear memories in mice by subjecting them to a mild electric shock in a specific chamber. This type of emotional memory is known for its ability to persist over time due to the intensity of the fear experienced. Once fear had been associated with the camera, the mice showed a freezing response when placed back in the same location, a typical behavior associated with traumatic or fear memories.
The researchers, by manipulating astrocytes in the brains of mice, discovered that by acidifying these cells immediately after the electric shock, fear memories disappeared the next day, that is, the mice quickly forgot the event. On the other hand, when astrocytes were alkalinized, emotional memories were maintained even three weeks after the traumatic event. This finding suggests that astrocytes not only modulate memory, but are also responsible for deciding whether a memory is forgotten or preserved long-term.
This study raises a new perspective on how memories are formed and maintained, suggesting that the relationship between neurons and astrocytes is crucial for the consolidation of memories, especially those that have a strong emotional component. Furthermore, these discoveries open the door to possible therapies for disorders such as post-traumatic stress disorder (PTSD), where traumatic memories can be managed or even eliminated.
Implications for understanding emotional memory
Discoveries about the role of astrocytes in the formation and maintenance of emotional memories have profound implications for the treatment of emotional disorders, especially those related to memory, such as post-traumatic stress disorder (PTSD). PTSD is characterized by the appearance of intrusive and disturbing memories of traumatic events, which seriously affect the quality of life of those who suffer from it. These persistent memories often trigger symptoms such as anxiety, insomnia, and intense fear reactions.
The ability to manipulate astrocytes and their influence on the consolidation of emotional memories could offer an innovative approach to the treatment of PTSD. By modifying the chemical state of astrocytes, for example by alkalinizing them, it might be possible to preserve important memories while reducing or even eliminating unwanted traumatic memories. This technology could be a more precise and less invasive alternative to current treatmentswhich generally include cognitive behavioral therapy or the use of medications such as antidepressants.
Furthermore, research suggests that emotional memory is not formed sequentially, as previously thought, but rather that both short- and long-term memories can develop in parallel, opening new avenues for understanding how other types are consolidated. of memories, such as those related to learning. In the future, a deeper understanding of the role of astrocytes could allow the design of more specific and effective therapies, not only for PTSD, but also for other emotional disorders linked to memory.
Possible applications in treatments for memory disorders
This study on the role of astrocytes in emotional memory challenges previous theories about how memories are formed and consolidated. Traditionally, it was believed that short-term memories gradually transitioned into long-term memories, in a sequential process. However, the findings suggest that these two types of memories can develop simultaneously, with astrocytes playing a crucial role in this interaction.
The fact that the acidification of astrocytes prevents memory consolidation, while their alkalinization preserves it, indicates that these chemical changes could be a key to controlling the fate of memories. This new understanding could revolutionize the treatment of disorders such as PTSD, providing tools to manipulate traumatic memories more precisely.
Likewise, this study opens the door to additional research into how astrocytes can influence other types of memory, such as memory related to learning or brain aging. The field of neuroscience is advancing rapidly, and the active role of astrocytes in the formation of memories could be a key element in developing innovative therapies, not only for emotional disorders, but also for neurodegenerative diseases such as Alzheimer’s.
In conclusion, the study of astrocytes and their influence on emotional memory marks a significant advance in neuroscience. These findings challenge previous theories about memory consolidation, suggesting that short- and long-term memories can form in parallel, with astrocytes playing a key role in their fate. This new perspective could open avenues for innovative treatments for emotional disorders such as PTSD, allowing traumatic memories to be manipulated more precisely. As research advances, new therapeutic applications are likely to emerge that improve the treatment of memory-related diseases.
I’m Emily Williams Jones, a psychologist specializing in mental health with a focus on cognitive-behavioral therapy (CBT) and mindfulness. With a Ph.D. in Psychology, my career has spanned research, clinical practice and private counseling. I’m dedicated to helping individuals overcome anxiety, depression and trauma by offering a personalized, evidence-based approach that combines the latest research with compassionate care.
