Name: Squid Giant Axon Membrane Potential
Published: April 15, 2016
License: https://opendatacommons.org/licenses/by/index.html

Database Open Access

Published: April 15, 2016. Version: 1.0.0

New Database Added: SGAMP (April 15, 2016, 1 a.m.)

The Squid Giant Axon Membrane Potential database contains single-unit neuronal recordings of squid giant axons in response to stimulus currents. The membrane potential and stimulus current are given for a total of 170 trials across 8 different axons.

When using this resource, please cite the original publication:

Paydarfar D, Forger DB, Clay JC. Noisy Inputs and the Induction of On–Off Switching Behavior in a Neuronal Pacemaker. Journal of Neurophysiology, 96:3338-3348, 2006.

Please include the standard citation for PhysioNet: (show more options)
Goldberger, A., Amaral, L., Glass, L., Hausdorff, J., Ivanov, P. C., Mark, R., ... & Stanley, H. E. (2000). PhysioBank, PhysioToolkit, and PhysioNet: Components of a new research resource for complex physiologic signals. Circulation [Online]. 101 (23), pp. e215–e220.

APA	Goldberger, A., Amaral, L., Glass, L., Hausdorff, J., Ivanov, P. C., Mark, R., ... & Stanley, H. E. (2000). PhysioBank, PhysioToolkit, and PhysioNet: Components of a new research resource for complex physiologic signals. Circulation [Online]. 101 (23), pp. e215–e220.
MLA	Goldberger, A., et al. "PhysioBank, PhysioToolkit, and PhysioNet: Components of a new research resource for complex physiologic signals. Circulation [Online]. 101 (23), pp. e215–e220." (2000).
CHICAGO	Goldberger, A., L. Amaral, L. Glass, J. Hausdorff, P. C. Ivanov, R. Mark, J. E. Mietus, G. B. Moody, C. K. Peng, and H. E. Stanley. "PhysioBank, PhysioToolkit, and PhysioNet: Components of a new research resource for complex physiologic signals. Circulation [Online]. 101 (23), pp. e215–e220." (2000).
HARVARD	Goldberger, A., Amaral, L., Glass, L., Hausdorff, J., Ivanov, P.C., Mark, R., Mietus, J.E., Moody, G.B., Peng, C.K. and Stanley, H.E., 2000. PhysioBank, PhysioToolkit, and PhysioNet: Components of a new research resource for complex physiologic signals. Circulation [Online]. 101 (23), pp. e215–e220.
VANCOUVER	Goldberger A, Amaral L, Glass L, Hausdorff J, Ivanov PC, Mark R, Mietus JE, Moody GB, Peng CK, Stanley HE. PhysioBank, PhysioToolkit, and PhysioNet: Components of a new research resource for complex physiologic signals. Circulation [Online]. 101 (23), pp. e215–e220.

Abstract

The SGAMP database contains single-unit neuronal recordings of North Atlantic squid (Loligo pealei) giant axons in response to stimulus currents. The membrane potential and stimulus current are given for a total of 170 trials across 8 different axons.

Data Desciption

The applied stimulus current profiles can be divided into two groups: Stochastically summated polysynaptic currents (PSCs), and individual current pulses. Refer to the original publication for technical details, and see the Recording-Info.ods spreadsheet for information about each trial. In addition, the Irms file contains the root mean squared stimulus current values in uA/cm2. This only applies to stochastic current records when the stimulation is on; current pulse records are marked 'PULSE'.

The files in the raw directory contain the original raw values captured by the DATAQ Instruments capturing device (translated into MIT format). Both channels are given in volts, and have not been calibrated or translated into their physical units. In order to convert the raw recorded values into physical units:

For the membrane potential channel (1), multiply the values by 0.1 to remove the instrumentation gain. This gives the membrane potential in volts.
For the stimulus current channel (2), apply the physical unit conversion, 1V = 5uA/cm2 to get the stimulus current in uA/cm2. Note that current recordings may have a DC offset due to the recording instrumentation, which does not reflect an offset of applied current. When the stimulation current is off, the baseline should be zero.

File names are in the form aXtY, where X is the axon number and Y is the trial number for that axon. Each record lasts in the order of several seconds and is sampled at 125KHz.

References

The data set is also used in

Forger DB, Paydarfar D, Clay JR, Optimal Stimulus Shapes for Neuronal Excitation.PLoS Computational Biology 7(7):e1002089, 2011.
Clay JR, Forger DB, Paydarfar D, Ionic Mechanism Underlying Optimal Stimuli for Neuronal Excitation: Role of Na+ Channel Inactivation. PLoS One 7(9):e45983, 2012.
Bod’ová K, Paydarfar D, Forger DB, Characterizing Spiking in Noisy Type II Neurons. Journal of Theoretical Biology 365:40-54, 2015.

Access

Access Policy:
Anyone can access the files, as long as they conform to the terms of the specified license.

License (for files):
Open Data Commons Attribution License v1.0

Discovery

DOI (version 1.0.0):
https://doi.org/10.13026/C25C73

Topics:
neuron neuroelectric

Corresponding Author

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Files

Total uncompressed size: 901.7 MB.

Access the files

Download the ZIP file (901.7 MB)
Access the files using the Google Cloud Storage Browser here. Login with a Google account is required.
Access the data using the Google Cloud command line tools (please refer to the gsutil documentation for guidance):
```
gsutil -m -u YOUR_PROJECT_ID cp -r gs://sgamp-1.0.0.physionet.org DESTINATION
```

Download the files using your terminal:

wget -r -N -c -np https://physionet.org/files/sgamp/1.0.0/

Download the files using AWS command line tools:

aws s3 sync --no-sign-request s3://physionet-open/sgamp/1.0.0/ DESTINATION

Visualize waveforms

Folder Navigation:

Name	Size	Modified
raw
Irms.txt (download)	2.6 KB	2016-04-16
RECORDS (download)	1.7 KB	2016-04-16
Recording-Info.ods (download)	54.1 KB	2016-04-16
SHA256SUMS.txt (download)	26.5 KB	2019-02-20

Squid Giant Axon Membrane Potential

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