Behavior is controlled by neural activity in the brain. The final outcome o
f this neural control may critically depend on the firing reliability of in
dividual neurons. A nearly constant, proportional relationship is usually f
ound between the response mean and response variance. Here we asked whether
lateral interactions within striate cortex that modulate response magnitud
e also proportionately modify the response variance of cortical neurons. In
many cases, response variability depended on stimulus organization: discre
te flankers colinearly placed well outside the neuron's receptive field inc
reased response magnitude without a proportional increase in variance, thus
improving the neuron's response reliability. Since colinear flanker facili
tation is often seen near the neuron's firing threshold, increased response
reliability for weak stimuli may contribute to enhancing perceptual salien
cy.