In a recent study conducted by researchers from the Netherlands Institute for Neuroscience, it has been discovered that chandelier cells, a specific type of brain cell, become active during unexpected situations. This finding sheds light on the functionality of these cells, which has been a subject of curiosity among researchers for a long time.
The study aimed to understand how the brain signals and processes unexpected changes, as well as which cells are involved in this process. To delve deeper into this phenomenon, the researchers, led by Koen Seignette from Christiaan Levelt’s lab, joined forces with colleagues from the Kole lab and Roelfsema lab. Together, they focused on a unique type of brain cell called chandelier cells, which are found in small numbers in the cortex.
Unlike other inhibitory brain cells, chandelier cells inhibit only one spot of other cells. However, little is known about the exact function and timing of these cells. Therefore, the researchers developed a mouse model wherein the chandelier cells were fluorescently labeled, enabling live imaging and determining their activity.
The team began their investigation by analyzing how chandelier cells in the visual cortex respond to various stimuli. They observed that the specific type of stimulus did not matter as much as the element of surprise. Whether the mouse was running or visual stimuli were presented, the chandelier cells showed a strong reaction during unexpected events. Interestingly, they also noticed that habituation and change occurred, similar to the example of the new building in the city. Initially, the cells reacted strongly, but with repeated exposure, their activity became weaker.
This adaptability of the cells demonstrates plasticity, which is the ability to change and adjust based on new information. Moreover, the researchers observed structural changes in the synapses formed by chandelier cells on other brain cells, further highlighting the concept of plasticity.
The significance of this study lies in its comprehensive examination of chandelier cells in the visual cortex, providing insights into their response patterns, connectivity with other brain cells, and influence on brain function. Understanding the role of inhibitory neurons like chandelier cells is crucial for various processes, including learning from unexpected circumstances. It is a widely known fact that individuals remember things better when they surprise them, with incorrect predictions offering valuable information. Plasticity is essential for updating insights, and chandelier cells could play a role in facilitating this process.
Chandelier cells, so named because of their resemblance to chandeliers, are inhibitory brain cells that focus on the starting point of electrical signals in pyramidal cells, which are the most common cells in the cortex. Previous assumptions suggested that chandelier cells exert strong control over pyramidal cells by blocking action potentials. However, the recent research demonstrates that the inhibitory effect of chandelier cells is actually weak, contradicting previous conclusions.
This study marks a significant advancement in our understanding of chandelier cells and their role in reacting to unexpected situations. Further research in this area will undoubtedly contribute to our knowledge of brain function and its implications for learning and adaptation.
