The current research will take advantage of recently developed high-resolution functional MRI techniques to observe population-level responses in monkeys and humans performing the same covert attention task. Initially, frontal and parietal areas that have topographic maps of the visual field will be identified using more complex cognitive tasks, such as a delayed saccade and a working memory task. Functional regions of interest will be defined from topographic areas in order to investigate their role in visual spatial attention. Both species will perform a covert attention task to identify the network of brain regions involved in attentional processes for each species. Data analysis techniques will include a functional region of interest analysis along with more traditional cluster-level analysis based on whole-brain normalization. The relationship between topographic areas and those recruited during spatially directed attention will be investigated. Areas identified as part of the attentional network will be compared across species, using converging evidence from prior research and the current topographic and attentional studies in order to identify analogous regions. These studies will provide information about target sites for future invasive studies in animals using single-cell physiology or lesion methods. ? ? ?
McMains, Stephanie; Kastner, Sabine (2011) Interactions of top-down and bottom-up mechanisms in human visual cortex. J Neurosci 31:587-97 |
McMains, Stephanie A; Kastner, Sabine (2010) Defining the units of competition: influences of perceptual organization on competitive interactions in human visual cortex. J Cogn Neurosci 22:2417-26 |