Summary: *Correspondence address. Volen Center for Complex Systems, Brandeis University, 415 South Street
MS013 Waltham, MA 02454 USA. Tel.: #1-781-736-3134; fax: #1-781-736-3142.
E-mail address: firstname.lastname@example.org (M.S. Goldman).
Neurocomputing 32}33 (2000) 141}146
Dependence of "ring pattern on intrinsic ionic conductances:
Sensitive and insensitive combinations
Mark S. Goldman *, Jorge Golowasch , Eve Marder , L.F. Abbott
Volen Center for Complex Systems, Brandeis University, 415 South Street MS013 Waltham, MA 02454 USA
Department of Physics, Harvard University, Cambridge, MA 02138 USA
Accepted 13 January 2000
We construct maps of the intrinsic "ring state (silent, tonically "ring, or bursting) of a model
neuron as a function of its maximal ionic conductances. The "ring properties vary signi"cantly
only in response to changes in particular, sensitive combinations of conductances that may
serve as targets for neuromodulation. Less sensitive combinations de"ne directions along which
neuronal conductances may drift without triggering signi"cant changes in "ring activity. This
suggests that neurons may have similar functional properties despite widely varying conduc-
tance densities. 2000 Elsevier Science B.V. All rights reserved.
Keywords: Conductance-based model; Activity-dependent regulation; Neuromodulation;