TY - JOUR T1 - Deterministic Multiplicative Gain Control with Active Dendrites JF - The Journal of Neuroscience JO - J. Neurosci. SP - 9968 LP - 9977 DO - 10.1523/JNEUROSCI.2682-05.2005 VL - 25 IS - 43 AU - W. Hamish Mehaffey AU - Brent Doiron AU - Leonard Maler AU - Ray W. Turner Y1 - 2005/10/26 UR - http://www.jneurosci.org/content/25/43/9968.abstract N2 - Multiplicative gain control is a vital component of many theoretical analyses of neural computations, conferring the ability to scale neuronal firing rate in response to synaptic inputs. Many theories of gain control in single cells have used precisely balanced noisy inputs. Such noisy inputs can degrade signal processing. We demonstrate a deterministic method for the control of gain without the use of noise. We show that a depolarizing afterpotential (DAP), arising from active dendritic spike backpropagation, leads to a multiplicative increase in gain. Reduction of DAP amplitude by dendritic inhibition dilutes the multiplicative effect, allowing for divisive scaling of the firing rate. In contrast, somatic inhibition acts in a subtractive manner, allowing spatially distinct inhibitory inputs to perform distinct computations. The simplicity of this mechanism and the ubiquity of its elementary components suggest that many cell types have the potential to display a dendritic division of neuronal output. ER -