Canonical neurons and their parts
 This database
stores experimental data for each of the main parts of a neuronal type. Because
neurons display a variety of shapes, it makes a logical and universally
applicable classification of their parts very difficult. The approach taken here
is to use a simplified representation based on the idea of a canonical form,
e.g., the simplest form that represents the main neuronal regions. The
abbreviations for the canonical parts of a neuron are: D, dendrite; S, soma
(cell body); AH, axon hillock-initial segment of the axon; A, axon; T, axon
terminal.
Representation of canonical forms of different neurons
requires, in addition, a way of representing the diversity of their dendritic
trees. The simplest case is a single dendrite, represented as an equivalent
cylinder (e) consisting of a chain of three compartments, designated as (p)
proximal, (m) middle, and (d) distal with respect to the cell body. More
complicated are various multipolar branching patterns. The approach taken here
is to follow Rall and Shepherd (1968) in representing these patterns as
equivalent dendrites, with corresponding p, m and d compartments. This is
appropriate for most experimental data, which are reported in terms of these
three critical regions. More complicated still are the dendritic trees of
neurons with apical and basal dendritic trees. These are each represented here
by apical (a) and basal (b) equivalent dendrites, each with its p, m, and d
compartments. Variations on these basic forms may be noted in the annotation
boxes.
These categories are the basis for organizing the
submission and the viewing of the experimental data relevant to the neurons in
this database.
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