Re: colocalization between confocal and two-photon: voxel matching

Posted by Jeremy Adler-4 on
URL: http://confocal-microscopy-list.275.s1.nabble.com/xyzt-image-tp7580102p7580115.html

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Surprisingly actually measuring colocalization is surprisingly tricky  
- there are far too many coefficients and nonsense to several decimal  
places is still nonsense.

It is also important to appreciate that colocalization addresses two  
separate questions (1) cooccurence, are the molecules in the same  
pixels and (2) correlation, is there any relationship between the  
intensities. These cannot be measured with a single coefficient.

It is also important to appreciate that the quality, meaning noise, of  
the individual images seriously alters the measured colocalization.  
Try taking a second image and comparing it to the first - they are  
unlikely to be identical and for a correlation measurement this noise  
creates a difference between the measured and the true (noise free)  
correlation. A solution to the problem of noise is available for  
correlation measurements.

look at

http://diva-portal.org/smash/record.jsf?searchId=11&pid=diva2:563664


Jeremy Adler
IGP
Rudbeckslaboratoriet
Daghammersköljdsväg 20
751 85 Uppsala
Sweden

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