idw – Informationsdienst Wissenschaft

Nachrichten, Termine, Experten

Grafik: idw-Logo
Grafik: idw-Logo

idw - Informationsdienst
Wissenschaft

Science Video Project
idw-Abo

idw-News App:

AppStore

Google Play Store



Instance:
Share on: 
04/13/2011 18:00

Spatial Memory: Place cells lie in wait

Johannes Faber Bernstein Koordinationsstelle
Nationales Bernstein Netzwerk Computational Neuroscience

    Researchers at the Bernstein Center Berlin and the Humboldt University discover cells to prepare early for their spatial memory task

    Memories, places and actions are stored in our brain. But what determines for a certain task the contribution of specific nerve cells out of billions of cells? For a long time scientists debated whether the cell’s activation in a specific brain region during a particular case is random or not. Jèrôme Epsztein, Michael Brecht, and Albert K. Lee of the Bernstein Center Berlin and the Humboldt University of Berlin now proved clearly that the cells are not chosen randomely. At the example of spatial memory in rats they showed that later active cells differ early from their quiet neighbors. Their findings push the understanding of memory formation a major step forward.
    If we move in an unknown environment, a neuronal map is created in our brain. Particularly well understood is the memory function in rats. Cells of the rat’s hippocampus ensure that an animal always knows its location. Each of these so-called place cells is particularly active when the rat is in a certain area; the cell “fires”. Thus, each site is coded by specific cells. However, in the corresponding region of the brain are also cells that do not fire, they are "silent". This activity pattern and the selection of active cells is very specific for a particular environment.

    Using a sophisticated method Jèrôme Epsztein, Michael Brecht, and Albert K. Lee succeeded for the first time measuring the electrical properties within individual cells of the hippocampus, while the animals were freely moving. They studied the electrical base line and the current level from which individual cells responded with a stimulus response - the so-called threshold. The scientists measured cell activity before, during and after exploration. Therefore they could compare the behavior of silent cells and place cells before the first site-specific activity. They found that place cells showed from the outset a lower threshold and different discharge patterns.

    The scientists assume cell-intrinsic properties to be responsible for these differences. This triggers a series of new questions: What factors account for the differences? How are these cell properties set? Are these properties changed if other cells are active in a different environment? In humans, the hippocampus is central for the transformation of content of the short-term into the long-term memory. Dysfunctions in this brain region result in anterograde amnesia. In such cases, memories remain, but new information cannot be permanently stored. With their results, scientists contribute to a better understanding of our memory.

    The Bernstein Center Berlin is part of the Bernstein Network Computational Neuroscience (NNCN) in Germany. The NNCN was established by the German Federal Ministry of Education and Research with the aim of structurally interconnecting and developing German capacities in the new scientific discipline of computational neuroscience. It was named in honor of the German physiologist Julius Bernstein (1835–1917).

    Original Publication:
    Epsztein et al., Intracellular Determinants of Hippocampal CA1 Place and Silent Cell Activity in a Novel Environment,
    Neuron (2011), doi:10.1016/j.neuron.2011.03.006

    For further information please contact:
    Prof. Michael Brecht, Bernstein Center Berlin and Humboldt University Berlin, michael.brecht@bccn-berlin.de, Tel.:030-2093 6772


    More information:

    http://www.bccn-berlin.de Bernstein Center Berlin
    http://www.nncn.de National Bernstein Network Computational Neuroscience


    Images

    When the animal crosses area A, specific cells are active, whereas others "fire" while crossing area B. These so-called place cells are the basis of spatial memory.
    When the animal crosses area A, specific cells are active, whereas others "fire" while crossing area ...
    Graphic: BCOS, mod. after Epsztein et al. 2011
    None


    Criteria of this press release:
    Journalists, Scientists and scholars, all interested persons
    Biology, Medicine, Zoology / agricultural and forest sciences
    transregional, national
    Research results
    English


     

    Help

    Search / advanced search of the idw archives
    Combination of search terms

    You can combine search terms with and, or and/or not, e.g. Philo not logy.

    Brackets

    You can use brackets to separate combinations from each other, e.g. (Philo not logy) or (Psycho and logy).

    Phrases

    Coherent groups of words will be located as complete phrases if you put them into quotation marks, e.g. “Federal Republic of Germany”.

    Selection criteria

    You can also use the advanced search without entering search terms. It will then follow the criteria you have selected (e.g. country or subject area).

    If you have not selected any criteria in a given category, the entire category will be searched (e.g. all subject areas or all countries).