  Cells constantly need to monitor the state of the environment to detect
changes and timely respond. The detection of concentration changes of a ligand
by a set of receptors can be cast as a problem of hypothesis testing, and the
cell viewed as a Neyman-Pearson detector. Within this framework, we investigate
the role of receptor cooperativity in improving the cell's ability to detect
changes. We find that cooperativity decreases the probability of missing an
occurred change. This becomes especially beneficial when difficult detections
have to be made. Concerning the influence of cooperativity on how fast a
desired detection power is achieved, we find in general that there is an
optimal value at finite levels of cooperation, even though easy discrimination
tasks can be performed more rapidly by noncooperative receptors.

Quantitative Methods;Statistical Mechanics;Biological Physics;Molecular Networks