MemoryCodes · Time and experience dependent evolution of hippocampal memory codes
7РП — „Хора“ (Действия „Мария Кюри“)
- Период
- 2014-06-01 → 2018-05-31
- Финансиране от ЕС
- 100 000 €
- Участници
- 1
- Схема
- MC-CIG
Линиите свързват координатора с партньорите.
Накратко на български
Невронните кодове в хипокампуса на мишки се променят според времето и опита, например при посещение на различни места. Това помага да се разбере как мозъкът маркира събитията във времето, за да формира дългосрочна памет.
Кратко обяснение, генерирано от езиков модел по текста на CORDIS. Оригиналът е по-долу.
Резултати накратко
Time and experience dependent evolution of hippocampal memory codes
Project MemoryCodes aimed to characterize how time and experience interact to drive changes in hippocampal memory codes. To study neural coding of long-term memory we combined miniature fluorescence microscopes, microendoscope lenses, and genetically encoded indicators of neuronal activity to perform chronic Ca2+-imaging in the hippocampus of a freely behaving mice. We recently developed CellReg, a probabilistic method that automatically registers cells across multiple sessions and estimates the registration confidence for each registered cell (Sheintuch et al, Cell Reports 2017). Using large-scale Ca2+ imaging data recorded over weeks from the hippocampus and cortex of freely behaving mice, we showed that CellReg performs more accurate registration than previously used routines, yielding estimated error rates <5%, and that the registration is scalable for many sessions. Thus, our method allows reliable longitudinal analysis of the same neurons over long time periods, which is essential for studying neural coding of long-term memory. In another study (Rubin et al, eLife 2015), we performed time-lapse imaging of thousands of neurons over weeks in the hippocampal CA1 of mice as they repeatedly visited two distinct environments. Longitudinal analysis exposed ongoing environment independent evolution of episodic representations, despite stable place field locations and constant remapping between the two environments. These dynamics time-stamped experienced events via neuronal ensembles that had cellular composition and activity patterns unique to specific points in time. Temporally close episodes shared a common timestamp regardless of the spatial context in which they occurred. Temporally remote episodes had distinct timestamps, even if they occurred within the same spatial context. Our results suggest that days-scale hippocampal ensemble dynamics could support the formation of a mental timeline in which experienced events could be mnemonically associated or dissociated based on their temporal distance.
Текст от CORDIS, на английски · Данни: CORDIS, © Европейски съюз
Цел на проекта
Following initial learning, information stored in memory undergoes a time- and experience-dependent evolution. Currently, the nature of this evolution at the neuronal ensemble level remains largely unknown. To obtain insight into this dynamic process there is a need to follow memory-associated neuronal representations in large populations of single cells over long periods of time. However, until recently it has been nearly technically impossible to obtain the requisite data. In my postdoctoral work I have developed an experimental system that enables such investigation by longitudinally imaging neuronal activity in more than 1,000 neurons simultaneously in the hippocampus of freely behaving rodents over the course of months. To enable high-speed imaging at cellular resolution in deep brain structures, my system combines four recent technical advances: (i) miniaturized head-mounted fluorescence microscopes for use in freely behaving mice; (ii) microendoscope probes, for high-resolution imaging of cells in deep brain structures pertinent to long-term memory; (iii) a chronic mouse preparation that permits longitudinal imaging over months of individual neurons lying deep in the brain; (iv) genetically encoded Ca2+ indicators to report neuronal activity. To investigate the principles of neural coding of long-term memory and their underlying biological mechanisms, my lab will combine this imaging methodology with genetic tools for manipulating neuronal activity in specific hippocampal cell types, and novel computational methods for analyzing data from large-scale neuronal populations. This proposal aims to determine how hippocampal place coding evolves as a function of learning and passage of time, and how adult neurogenesis shapes hippocampal information processing. Our results may have profound implications to our understanding of long-term memory and to the study of brain disorders, such as Alzheimer disease and age-related memory loss.
Оригинален текст от CORDIS (на английски).
Участници
- WEIZMANN INSTITUTE OF SCIENCE · RehovotКоординаторИзраел
Връзки
Данни: CORDIS, © Европейски съюз