The intervals at which homogeneous flashes recover masked targets.
The recovery effect may be induced by the introduction of a homogeneous blank flash after a patterned mask. It is not clear which parameters optimize the effect. In this study, the effect of systematical variation of the different interstimulus intervals on performance was investigated. Conditions in which the blank flash preceded the patterned mask were included. The important parameter is shown to be the interval between Mask 1 and Mask 2. For optimal recovery, this value has to be 0–20 msec. It is argued that these results, as well as a number of other recovery findings, can be explained by the suppressing influence of homogeneous flashes on contour processing channels in the visual system.
It is the purpose of this paper to introduce a novel estimator for the extremal index of an instantaneous function {f(Xn)}n of a regenerative Harris Markov chain X, based on the renewal properties of the latter. The estimate proposed may be viewed as a "regenerative version" of the runs estimator, insofar as it measures the clustering tendency of high threshold exceedances within regeneration cycles. Strong consistency of this estimator is established under mild stochastic stability assumptions and a simulation result is displayed in the case when the underlying chain is the waiting process related to a simple M/M/1 queue.