title: Extended dynamic clamp: controlling up to four neurons using a single desktop computer and interface.
abstract: The dynamic clamp protocol allows an experimenter to simulate the presence of membrane conductances in, and synaptic connections between, biological neurons. Existing protocols and commercial ADC/DAC boards provide ready control in and between < or =2 neurons. Control at >2 sites is desirable when studying neural circuits with serial or ring connectivity. Here, we describe how to extend dynamic clamp control to four neurons and their associated synaptic interactions, using a single IBM-compatible PC, an ADC/DAC interface with two analog outputs, and an additional demultiplexing circuit. A specific C++ program, DYNCLAMP4, implements these procedures in a Windows environment, allowing one to change parameters while the dynamic clamp is running. Computational efficiency is increased by varying the duration of the input-output cycle. The program simulates < or =8 Hodgkin-Huxley-type conductances and < or =18 (chemical and/or electrical) synapses in < or =4 neurons and runs at a minimum update rate of 5 kHz on a 450 MHz CPU. (Increased speed is possible in a two-neuron version that does not need auxiliary circuitry). Using identified neurons of the crustacean stomatogastric ganglion, we illustrate on-line parameter modification and the construction of three-member synaptic rings.
authors.affiliation: Institute for Nonlinear Science, University of California, San Diego, 9500 Gilman Dr. #0402, La Jolla, CA 92093-0402, USA. reynaldo@ucsd.edu
authors.forename: R D
authors.initials: RD
authors.lastname: Pinto
authors.forename: R C
authors.initials: RC
authors.lastname: Elson
authors.forename: A
authors.initials: A
authors.lastname: Szücs
authors.forename: M I
authors.initials: MI
authors.lastname: Rabinovich
authors.forename: A I
authors.initials: AI
authors.lastname: Selverston
authors.forename: H D
authors.initials: HD
authors.lastname: Abarbanel
mesh_terms: D000465:Algorithms; D000818:Animals; D003199:Computer Systems; D003445:Crustacea / Q000502:physiology; D017952:Ganglia, Invertebrate / Q000502:physiology; D008564:Membrane Potentials / Q000502:physiology*; D008838:Microcomputers / Q000592:standards / Q000639:trends; D008959:Models, Neurological; D009415:Nerve Net / Q000502:physiology*; D009434:Neural Pathways / Q000502:physiology*; D018408:Patch-Clamp Techniques / Q000295:instrumentation*; D009435:Synaptic Transmission / Q000502:physiology*; D014584:User-Computer Interface