Estimation of the variance of the variance: implications for multiple-probability fluctuation analysis at central synapses

Chiara Saviane; R. Angus Silver

doi:10.1117/12.546767

25 May 2004 Estimation of the variance of the variance: implications for multiple-probability fluctuation analysis at central synapses

Chiara Saviane, R. Angus Silver

Author Affiliations +

Proceedings Volume 5467, Fluctuations and Noise in Biological, Biophysical, and Biomedical Systems II; (2004) https://doi.org/10.1117/12.546767
Event: Second International Symposium on Fluctuations and Noise, 2004, Maspalomas, Gran Canaria Island, Spain

Abstract

Synapses play a crucial role in information processing in the brain. Amplitude fluctuations of synaptic responses can be used to extract information about the mechanisms underlying synaptic transmission and its modulation. In particular, multiple-probability fluctuation analysis uses the variance and mean amplitude of postsynaptic responses, recorded at different probabilities, to estimate the number of functional releasing sites, the mean probability of release and the amplitude of single quantal responses. We investigated the best estimators of the variance of the variance in order to improve the estimates of quantal parameters. We used simulations of synaptic transmission to test the accuracy and reliability of estimators under different experimental conditions. For central synapses, which generally have a low number of releasing sites, the amplitude distribution of synaptic responses is not normal, thus the use of a theoretical variance of the variance based on the normal assumption is not a good approximation. However, appropriate estimators can be derived for the population and for limited sample sizes using a more general expression that involves higher moments and introducing unbiased estimators based on the h-statistics. Our results are likely to be relevant for various applications of fluctuation analysis when few channels or releasing sites are present.

Citation Download Citation

Chiara Saviane and R. Angus Silver "Estimation of the variance of the variance: implications for multiple-probability fluctuation analysis at central synapses", Proc. SPIE 5467, Fluctuations and Noise in Biological, Biophysical, and Biomedical Systems II, (25 May 2004); https://doi.org/10.1117/12.546767

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available