h1. Cell Types Data

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h1. Searching the Database

With the initial launch of the Allen Cell Types Database, we include electrophysiological recordings from 248 individual cells,



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h2. Filters

h2. Cell Feature Filters

h2. Stimulus Types

h3. ELECTROPHYSIOLOGY STIMULI STRATEGY AND DETAILS

Different sets of stimulation waveforms were used in order to:

{fancy-bullets:image=circle} Interrogate intrinsic membrane mechanisms that underlie the input/output function of neurons
## Linear and non-linear subthreshold properties
## Action potential initiation and propagation
## Afterhyperpolarization/afterdepolarization
# Understand aspects of neural response properties in vivo
## Stimulation frequency dependence (theta vs. gamma) of spike initiation mechanisms
# Ion channel states due to different resting potentials in vivo
# Construct and test computational models of varying complexity emulating the neural response to stereotyped stimuli
## Generalized leaky-integrate-and-fire (GLIF) models
## Biophysically and morphologically realistic conductance-based compartmental models{fancy-bullets}

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h2. Neuronal Models

The Allen Cell Types Database contains two types of neuronal models:  perisomatic biophysical models and generalized leaky integrate-and-fire  (GLIF) models.  These models attempt to mathematically reproduce a  cell's recorded response to a current injection.  The perisomatic  biophysical models take into account dendritic morphological structure,  whereas GLIF models are simple point neuron models which represent the  neuron as a single compartment.

There are five levels of GLIF models with increasing levels of  complexity.  The most basic model is a simple leaky integrate-and-fire  equation.  More advanced GLIFs attempt to model variable spike  threshold, afterspike currents, and threshold adaptation. 
|| Model Name \\ || Description \\ ||
| 1 Leaky Integrate and Fire (LIF) \\ | Standard circuit representation of a resistor and capacitor in parallel with a leaky membrane. \\ |
| 2 LIF + Reset Rules (LIF-R) \\ | LIF with biologically-derived threshold and voltage reset rules in addition to a biologically derived threshold decay. \\ |
| 3 LIF + Afterspike Currents (LIF-ASC) \\ | LIF with spike-induced currents to model long-term effects of voltage-activated ion channels. \\ |
| 4 LIF-R + Afterspike Currents (LIF-R-ASC) \\ | LIF with additional Reset Rules and Afterspike Currents. \\ |
| 5 LIF-R-ASC + Threshold Adaptation (LIF-R-ASC-A) \\ | All of the above, with an additional voltage-dependent component of threshold. \\ |
| Biophysical, perisomatic \\ | Models with active conductances at the soma and passive dendritic morphology based on full 3D reconstruction. |



h3. Generalized Leaky-Integrate-and-Fire (GLIF) Models

h3. Biophysical Models - Perisomatic