AM Angioy

Christopher L Buckley

D Schneider

DJ Mar

P Duchampviret

Thomas Nowotny

BMC Neuroscience

Christopher Buckley (4461583)

Thomas Nowotny (4462033)

Sussex Research Online

Moving beyond convergence in the pheromone system of the moth

Crossref

Springer - Publisher Connector

BioMed CentralBMC Neuroscience
ssOpen AccePoster presentation
Moving beyond convergence in the pheromone system of the moth
Christopher L Buckley* and Thomas Nowotny
Address: CCNR, Informatics, University of Sussex, Falmer, BN1 9QJ, UK
Email: Christopher L Buckley* - c.l.buckley@sussex.ac.uk
* Corresponding author    
Introduction
Male moths can sense and locate conspecific females
releasing small amounts of pheromone from more than a
mile away [1]. Integral to this behavior is the extraordi-
nary sensitivity of the male moths olfactory apparatus to
pheromone molecules. This apparatus involves the trans-
duction of molecular binding events in large populations
of olfactory receptor neurons (ORNs) and their conver-
gent projections onto relatively small numbers of neurons
in the macro glomerular complex (MGC). Schneider cal-
culated a behavioral threshold of the pheromone system
of 200 molecular binding events at the antennae [1].
Recently Angioy et al. have reported that fluctuations of
the male moths cardiac rhythm were elicited with a calcu-
lated 6 molecular events at the antennae [2]. While it has
been demonstrated that ORN are capable of producing
spikes after only a single molecular binding event the
overall sensitivity of the systems is limited by noise in the
from Eighteenth Annual Computational Neuroscience Meeting: CNS*2009
Berlin, Germany. 18–23 July 2009
Published: 13 July 2009
BMC Neuroscience 2009, 10(Suppl 1):P187 doi:10.1186/1471-2202-10-S1-P187
<supplement> <title> <p>Eighteenth Annual Computational Neuroscience Meeting: CNS*2009</p> </title> <editor>Don H Johnson</editor> <note>Meeting abstracts – A single PDF containing all abstracts in this Supplement is available <a href="http://www.biomedcentral.com/content/files/pdf/1471-2202-10-S1-full.pdf">here</a>.</note> <url>http://www.biomedcentral.com/content/pdf/1471-2202-10-S1-info.pdf</url> </supplement>
This abstract is available from: http://www.biomedcentral.com/1471-2202/10/S1/P187
© 2009 Buckley and Nowotny; licensee BioMed Central Ltd. 
Figure 1Page 1 of 2
(page number not for citation purposes)
BMC Neuroscience 2009, 10(Suppl 1):P187 http://www.biomedcentral.com/1471-2202/10/S1/P187Publish with BioMed Central   and  every 
scientist can read your work free of charge
"BioMed Central will be the most significant development for 
disseminating the results of biomedical research in our lifetime."
Sir Paul Nurse, Cancer Research UK
Your research papers will be:
available free of charge to the entire biomedical community
peer reviewed and published immediately upon acceptance
cited in PubMed and archived on PubMed Central 
yours — you keep the copyright
Submit your manuscript here:
http://www.biomedcentral.com/info/publishing_adv.asp
BioMedcentral
ORNs. The statistical properties of the convergence path-
ways from ORNs to the neurons of the MGC have been
suggested as a possible solution to this problem [3]. In
this work we analyze a statistical model in order to inves-
tigate whether the signal to noise (SNR) enhancement
properties of convergent projections are sufficient to
explain the sensitivity of moths to low pheromone con-
centrations.
Model and conclusion
The model comprises of an ensemble of N binary ele-
ments (representing the 17000 ORNs in the moth) that
are activated with probability Pn (1600/17000) and Pn+Ps
((1600+Ps)/17000) in presence or absence of pheromone,
respectively. The output of these units converges on a
McCulloch and Pitts neuron. Figure 1 shows the number
of false positives (positive behavioral response in the
absence of pheromone) against the convergence rate for
three different Ps values. Simulated (symbols) and analyt-
ical results assuming Poisson statistics (lines) are shown.
The data demonstrates that for a biologically plausible
convergence rate of 1000 the number of false positives
exceeds that found in experiments (zero in 30 subjects)
[1]. The solid line in Figure 2 shows the SNR against the
convergence rate. It shows that SNR calculated in moth
cannot be explained by simple convergence phenomena
for a convergence rate of 1000. In conclusion, the statisti-
cal properties of convergence may not be enough to
explain the sensitivity of the moth pheromone system.
The dashed line in Figure 2 gives the SNR for noise shap-
ing [4] which has been put forward as a candidate mech-
anism to explain the olfactory sensitivity of the moth.
Acknowledgements
This work was funded by the Biotechnology and Biological Sciences 
Research Council (grant no. BB/F005113/1).
References
1. Schneider D: Olfactory receptors for the sexual attractant
(bombykol) the silk moth.  In The Neurosciences Second Study Pro-
gram Rockefeller Univ Press; 1970:511-518. 
2. Angioy AM, Desogus A, Barbarossa IT, Anderson P, Hansson BS:
Extreme sensitivity in an olfactory system.  Chem Senses 2003,
28:279-284.
3. Duchampviret P, Duchamp A, Vigouroux M: Amplifying role of
convergence in olfactory system a comparative study of
receptor cell and 2nd-order neuron sensitivities.  J Neurophys
1989, 61:1085-1094.
4. Mar DJ, Chow CC, Gerstner W, Adams RW, Collins LL: Noise
shaping in populations of coupled model neurons.  PNAS 1999,
96:10450-10455.
Figure 2Page 2 of 2
(page number not for citation purposes)


file:///data/remote/core/dit/data/Springer-OA/pdf/58c/aHR0cDovL2xpbmsuc3ByaW5nZXIuY29tLzEwLjExODYvMTQ3MS0yMjAyLTEwLVMxLVAxODcucGRm.pdf

Moving beyond convergence in the pheromone system of the moth

Abstract

Similar works

Full text

Available Versions

Sussex Research Online

Crossref

Springer - Publisher Connector

Springer - Publisher Connector