Disruption of auditory spatial working memory by inactivation of the forebrain archistriatum in barn owls

Barn owls not only localize auditory stimuli with great accuracy, they also remember the locations of auditory stimuli and can use this remembered spatial information to guide their flight and strike. Although the mechanisms of sound localization have been studied extensively, the neurobiological basis of auditory spatial memory has not. Here we show that the ability of barn owls to orient their gaze towards and fly to the remembered location of auditory targets is lost during pharmacological inactivation of a small region in the forebrain, the anterior archistriatum. In contrast, archistriatal inactivation has no effect on stimulus-guided responses to auditory targets. The memory-dependent deficit is evident only for acoustic events that occur in the hemifield contralateral to the side that is inactivated. The data demonstrate that in the avian archistriatum, as in the mammalian frontal cortex, there exists a region that is essential for the expression of spatial working memory and that, in the barn owl, this region encodes auditory spatial memory.