Researchers identify a new brain mechanism, essential for the memory
Memory, or access to the stored information in the brain, is a key ability that allows us to adapt our behavior to all sorts of situations. Memories weaken with aging and certain cognitive disorders, such as dementia or autism. However, the brain mechanisms that allow the normal functioning of memory remain very poorly understood. A study led by UB researchers published in Science Advances describes an unidentified neural circuit which is essential for remembering contextual memories, those that allow us to recognize a place or associate it with a life experience.
Memory, or access to the stored information in the brain, is a key ability that allows us to adapt our behavior to all sorts of situations. Memories weaken with aging and certain cognitive disorders, such as dementia or autism. However, the brain mechanisms that allow the normal functioning of memory remain very poorly understood. A study led by UB researchers published in Science Advances describes an unidentified neural circuit which is essential for remembering contextual memories, those that allow us to recognize a place or associate it with a life experience.
Els estudis actuals apunten que lʼactivació de lʼhipocamp és necessària per evocar el record. Aquesta regió del cervell, però, conté una gran diversitat de neurones organitzades en múltiples subxarxes, i alhora rep diverses projeccions dʼaltres nuclis cerebrals, fet que dificulta destriar el paper de cadascun dʼaquests aspectes en el record.
Current studies suggest that the activation of the hippocampus is necessary to recall memory. This region of the brain, however, contains a wide range of neurons organized into multiple substations and at the same time it receives several projections from other brain nuclei, making it difficult to discern the role of the different parts in memory.
To treat this cellular complexity, researchers used mice and state-of-the-art methods such as optogenetics, to selectively manipulate some neural contacts during memory tests. Led by Carles Sindreu, from the Unit of Pharmacology at the Department of Basic Clinical Practice of the UB, the research team showed that the medial septum -a deep region of the brain- allows the activation of the hippocampus so that memories have room.
“The medial septum links sensory regions with cognitive centers where information is highly processed, such as the hippocampus, promoting the reactivation of memory in response to our environment”, notes Sindreu, also member of IDIBAPS. “The way in which the septum works is very odd: its axons silence the cells that inhibit the hippocampus, activating it accordingly. This mechanism activates other neurons that give way to information, causing the memory to be expressed in the form of a behavioural response”, highlights the expert.
The identification of this memory circuit will stimulate the study of medial septum in humans, which is understudied, and will allow researchers to do research on new therapeutic strategies to treat patients with memory deficits.
Article reference:
A. Sans-Dublanc et al. «Septal GABAergic inputs to CA1 govern contextual memory retrieval». Science Advances, October, 2020:, vol. 6, núm. 44, eaba5003.
DOI: 10.1126/sciadv.aba5003