Show Reference: "Multiplicative computation in a visual neuron sensitive to looming"

Multiplicative computation in a visual neuron sensitive to looming Nature, Vol. 420, No. 6913. (21 November 2002), pp. 320-324, doi:10.1038/nature01190 by Fabrizio Gabbiani, Holger G. Krapp, Christof Koch, Gilles Laurent
    abstract = {Multiplicative operations are important in sensory processing, but their biophysical implementation remains largely unknown. We investigated an identified neuron (the lobula giant movement detector, {LGMD}, of locusts) whose output firing rate in response to looming visual stimuli has been described by two models, one of which involves a multiplication. In this model, the {LGMD} multiplies postsynaptically two inputs (one excitatory, one inhibitory) that converge onto its dendritic tree; in the other model, inhibition is presynaptic to the {LGMD}. By using selective activation and inactivation of pre- and postsynaptic inhibition, we show that postsynaptic inhibition has a predominant role, suggesting that multiplication is implemented within the neuron itself. Our pharmacological experiments and measurements of firing rate versus membrane potential also reveal that sodium channels act both to advance the response of the {LGMD} in time and to map membrane potential to firing rate in a nearly exponential manner. These results are consistent with an implementation of multiplication based on dendritic subtraction of two converging inputs encoded logarithmically, followed by exponentiation through active membrane conductances.},
    address = {Division of Biology, California Institute of Technology, Pasadena, California 91125, USA.},
    author = {Gabbiani, Fabrizio and Krapp, Holger G. and Koch, Christof and Laurent, Gilles},
    day = {21},
    doi = {10.1038/nature01190},
    issn = {0028-0836},
    journal = {Nature},
    keywords = {ann, biology, neural-multiplication, visual},
    month = nov,
    number = {6913},
    pages = {320--324},
    pmid = {12447440},
    posted-at = {2012-10-02 08:23:28},
    priority = {2},
    title = {Multiplicative computation in a visual neuron sensitive to looming},
    url = {},
    volume = {420},
    year = {2002}

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Verschure says neurons don't seem to multiply. Gabbiani et al. say they might.