<p>It is generally not possible to measure where a single calcium ion is in three dimensional space. However, it is possible to measure <em>relative</em> calcium ion concentration across a population of neurons using Two-Photon-Microscopy.</p>

<p>I stress relative because it does not give you an exact concentration of Calcium in terms of micro-molar concentration. However it is good enough to extract relative spike times of a individual neurons within the population. </p>

<p>The way "Calcium Imaging" works is the experimenter loads a neuron or population of neurons with a fluorescing dye that "lights up"  in the presence of calcium. There are many such chemicals which are listed in this article <a href="http://www.sciencedirect.com/science/article/pii/S0896627312001729" rel="nofollow">here</a>. The one I personally see being used in articles a lot is FURA-2. </p>

<p>As for frequency it depends on the experiment typically range from 60Hz to <a href="http://www.sciencedirect.com/science/article/pii/S0896627312001729" rel="nofollow">490 Hz</a>.Be aware however the faster the sample rate is the more noise in the measurements. </p>

<p>Do note that these methods are highly invasive, and require brain slices <em>in vitro</em> or opening the skull <em>in vivo</em>. As far as I am aware no study has been done on live humans. Typically rats are used.</p>

CC BY-SA 3.0
2015-02-08T01:11:29.913Z
2015-02-08T01:11:29.913Z
xelo747
<p>Is it possible to determine the position of a single calcium ion or its population in the context of a three dimensional space with relatively good time frequency, say 1 Hz, taking into account possible dense presence of the other types of ions in the neighborhood?</p>

<p>The qeustion is asked in the strong relation to the nervous system, but any pure-theory or computer-simulation driven concepts are also welcome.</p>

<neuroscience><theoretical-neuroscience><computational-modeling>
Determining the position of the calcium ion in the three dimensional space
bluevoxel
# Determining the position of the calcium ion in the three dimensional space

(Asked by: username_0 on 2014-10-16)

Is it possible to determine the position of a single calcium ion or its population in the context of a three dimensional space with relatively good time frequency, say 1 Hz, taking into account possible dense presence of the other types of ions in the neighborhood?

The qeustion is asked in the strong relation to the nervous system, but any pure-theory or computer-simulation driven concepts are also welcome.

**Tags:** neuroscience, theoretical-neuroscience, computational-modeling


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## 1 answers

### Answer by username_1 on 2015-02-08. Score: 1

It is generally not possible to measure where a single calcium ion is in three dimensional space. However, it is possible to measure *relative* calcium ion concentration across a population of neurons using Two-Photon-Microscopy.

I stress relative because it does not give you an exact concentration of Calcium in terms of micro-molar concentration. However it is good enough to extract relative spike times of a individual neurons within the population.

The way "Calcium Imaging" works is the experimenter loads a neuron or population of neurons with a fluorescing dye that "lights up" in the presence of calcium. There are many such chemicals which are listed in this article [here](http://www.sciencedirect.com/science/article/pii/S0896627312001729). The one I personally see being used in articles a lot is FURA-2.

As for frequency it depends on the experiment typically range from 60Hz to [490 Hz](http://www.sciencedirect.com/science/article/pii/S0896627312001729).Be aware however the faster the sample rate is the more noise in the measurements.

Do note that these methods are highly invasive, and require brain slices *in vitro* or opening the skull *in vivo*. As far as I am aware no study has been done on live humans. Typically rats are used.


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