title: Wide-fieldin vivoneocortical calcium dye imaging using a convection-enhanced loading technique combined with simultaneous multiwavelength imaging of voltage-sensitive dyes and hemodynamic signals.
abstract: In vivocalcium imaging is an incredibly powerful technique that provides simultaneous information on fast neuronal events, such as action potentials and subthreshold synaptic activity, as well as slower events that occur in the glia and surrounding neuropil. Bulk-loading methods that involve multiple injections can be used for single-cell as well as wide-field imaging studies. However, multiple injections result in inhomogeneous loading as well as multiple sites of potential cortical injury. We used convection-enhanced delivery to create smooth, continuous loading of a large area of the cortical surface through a solitary injection site and demonstrated the efficacy of the technique using confocal microscopy imaging of single cells and physiological responses to single-trial events of spontaneous activity, somatosensory-evoked potentials, and epileptiform events. Combinations of calcium imaging with voltage-sensitive dye and intrinsic signal imaging demonstrate the utility of this technique in neurovascular coupling investigations. Convection-enhanced loading of calcium dyes may be a useful technique to advance the study of cortical processing when widespread loading of a wide-field imaging is required.
authors.affiliation: Weill Cornell Medical College, New York Presbyterian Hospital, Department of Neurological Surgery, Brain and Mind Research Institute, Brain and Spine Center, 525 East 68th Street, Box 99, New York, New York 10021.
authors.forename: Hongtao
authors.initials: H
authors.lastname: Ma
authors.affiliation: Weill Cornell Medical College, New York Presbyterian Hospital, Department of Neurological Surgery, Brain and Mind Research Institute, Brain and Spine Center, 525 East 68th Street, Box 99, New York, New York 10021 ; University of Sheffield, Department of Psychology, Sheffield S10 2TN, United Kingdom.
authors.forename: Samuel
authors.initials: S
authors.lastname: Harris
authors.affiliation: Weill Cornell Medical College, New York Presbyterian Hospital, Department of Neurological Surgery, Brain and Mind Research Institute, Brain and Spine Center, 525 East 68th Street, Box 99, New York, New York 10021 ; Geisel School of Medicine at Dartmouth, Hanover, New Hampshire 03755.
authors.forename: Redi
authors.initials: R
authors.lastname: Rahmani
authors.affiliation: Columbia University, Department of Neuroscience, New York, New York 10032.
authors.forename: Clay O
authors.initials: CO
authors.lastname: Lacefield
authors.affiliation: Weill Cornell Medical College, New York Presbyterian Hospital, Department of Neurological Surgery, Brain and Mind Research Institute, Brain and Spine Center, 525 East 68th Street, Box 99, New York, New York 10021.
authors.forename: Mingrui
authors.initials: M
authors.lastname: Zhao
authors.affiliation: Weill Cornell Medical College, New York Presbyterian Hospital, Department of Neurological Surgery, Brain and Mind Research Institute, Brain and Spine Center, 525 East 68th Street, Box 99, New York, New York 10021.
authors.forename: Andy G S
authors.initials: AG
authors.lastname: Daniel
authors.affiliation: Weill Cornell Medical College, New York Presbyterian Hospital, Department of Neurological Surgery, Brain and Mind Research Institute, Brain and Spine Center, 525 East 68th Street, Box 99, New York, New York 10021.
authors.forename: Zhiping
authors.initials: Z
authors.lastname: Zhou
authors.affiliation: Columbia University, Department of Neuroscience, New York, New York 10032.
authors.forename: Randy M
authors.initials: RM
authors.lastname: Bruno
authors.affiliation: University of Sheffield, Department of Psychology, Sheffield S10 2TN, United Kingdom.
authors.forename: Jason
authors.initials: J
authors.lastname: Berwick
authors.affiliation: Weill Cornell Medical College, New York Presbyterian Hospital, Department of Neurological Surgery, Brain and Mind Research Institute, Brain and Spine Center, 525 East 68th Street, Box 99, New York, New York 10021.
authors.forename: Theodore H
authors.initials: TH
authors.lastname: Schwartz
keywords: calcium imaging; convection-enhanced loading; intrinsic optical imaging; neurovascular coupling; optical recording