Researchers at the University of British Columbia (UBC) in Vancouver, Canada, have discovered which cells are responsible for remembering the objects around us in our daily lives. Brain cells that were previously unknown: ovoid neurons.
Published in the journal Nature Communications, this work could help improve the understanding of certain diseases such as epilepsy (chronic neurological disease, characterized by spontaneous seizures, caused by the hyperactivity of a group of neurons in the brain) or Alzheimer's (a neurodegenerative disease, mainly affecting the memory and cognitive functions of patients).
In experiments conducted on mice, the ovoid neurons therefore come into action when they come into contact with a new object. Thus, even months after being exposed to it, the mice remember it. Since the ovoid cells no longer activate when they encounter the same object again, this shows that " that they play a primary role in its recording, but not in its recognition", explains to Science and Future Mark Cembrowski, lead author of the study.
In order to prove this postulate, he and his team, during their research, carried out numerous tests. One of them consisted of " to light up " And " turn off " artificially ovoid neurons, in order to accurately determine their function in the brain. In this way, when they were " "extinguished", the mice were unable to register the objects presented to them. In contrast, when the ovoid cells were " lit » According to the researchers, the mice were again intrigued by objects that were already familiar to them.
Read also: Discovery: It’s not just neurons that play a role in memory!
A neuron with multiple functions
Mark Cembrowski points out that the ovoid neurons could have other functions. Indeed, they would also serve " cognitive alarm » according to the researcher. This means that these cells could potentially have a role in " controlling what mice pay attention to"They would therefore make it possible to detect certain dangers. "Further studies and research remain to be done to fully understand this alarm role", the researcher specifies.
Furthermore, and according to this study, abnormal activity of these hippocampal neurons could also cause epileptic seizures. They are caused by hyperactivity of certain neurons in the brain. According to the researcher, " Ovoid cells may play a crucial role in triggering seizures. However, the link between the two is not yet understood and remains to be studied.".
Finally, ovoid neurons also seem to participate in the development of Alzheimer's disease. Indeed, a deterioration in their function would lead to a lack of recognition of objects surrounding patients. One of the characteristics of this disease. In addition, Mark Cembrowski adds that this disease is characterized by an abnormal accumulation of certain proteins in the brain and that " ovoid neurons have different responses to these proteins". Studying these reactions could help us understand " where this surplus of proteins comes from,” according to the researcher.
Read also: Alzheimer's: How brain waves and light flashes restore memory
A surprising neuron
"These cells are surprising because of their complex functions, reduced to a simple structure," precise Mark Cembrowski. Indeed, although they have a key function in memory, ovoid neurons have a fairly simple structure. Furthermore, also somewhat surprisingly for researchers, although these cells are located in the hippocampus (a region of the brain that plays a central role in memory and spatial navigation), it would seem that they do not participate in spatial awareness. "A first" according to Mark Cembrowski.
"Many further studies remain to be done to improve the understanding of the full role of ovoid neurons as well as to demonstrate their similar functions in humans," concludes the researcher. In addition, understanding these neurons could allow us to develop treatments and therapies, particularly to combat epileptic seizures and Alzheimer's disease.
English 
French