Galia Avidan

Using fMRI and a psychophysical task involving letter identification Kleinschmidt et al. (2002) (this issue of Neuron) delineate two patterns of neural activation which manifest in different cortical regions: a transient activation correlated with the change of a percept and a longer-term hysteresis correlated with the maintenance of the percept. These findings are provocative and suggest that neural hysteresis is mediated by visual structures that interact with higher-order regions to support longer-term maintenance of a percept.