title: The hemodynamic impulse response to a single neural event.
abstract: This article investigates the relation between stimulus-evoked neural activity and cerebral hemodynamics. Specifically, the hypothesis is tested that hemodynamic responses can be modeled as a linear convolution of experimentally obtained measures of neural activity with a suitable hemodynamic impulse response function. To obtain a range of neural and hemodynamic responses, rat whisker pad was stimulated using brief (</=2 seconds) electrical stimuli consisting of single pulses (0.3 millisecond, 1.2 mA) combined both at different frequencies and in a paired-pulse design. Hemodynamic responses were measured using concurrent optical imaging spectroscopy and laser Doppler flowmetry, whereas neural responses were assessed through current source density analysis of multielectrode recordings from a single barrel. General linear modeling was used to deconvolve the hemodynamic impulse response to a single "neural event" from the hemodynamic and neural responses to stimulation. The model provided an excellent fit to the empirical data. The implications of these results for modeling schemes and for physiologic systems coupling neural and hemodynamic activity are discussed.
authors.affiliation: Psychology Department, University of Sheffield, Western Bank Sheffield, UK. a.j.martindale@sheffield.ac.uk
authors.forename: John
authors.initials: J
authors.lastname: Martindale
authors.forename: John
authors.initials: J
authors.lastname: Mayhew
authors.forename: Jason
authors.initials: J
authors.lastname: Berwick
authors.forename: Myles
authors.initials: M
authors.lastname: Jones
authors.forename: Chris
authors.initials: C
authors.lastname: Martin
authors.forename: Dave
authors.initials: D
authors.lastname: Johnston
authors.forename: Peter
authors.initials: P
authors.lastname: Redgrave
authors.forename: Ying
authors.initials: Y
authors.lastname: Zheng
mesh_terms: D000818:Animals; D002560:Cerebrovascular Circulation / Q000502:physiology*; D004594:Electrophysiology; D005260:Female; D017078:Laser-Doppler Flowmetry; D016018:Least-Squares Analysis; D016014:Linear Models; D008955:Models, Cardiovascular; D009474:Neurons / Q000502:physiology; D051381:Rats; D011919:Rats, Inbred Strains; D013003:Somatosensory Cortex / Q000098:blood supply* / Q000166:cytology / Q000502:physiology*