title: Functional magnetic resonance imaging of single motor events reveals human presupplementary motor area.
abstract: Conventional functional imaging paradigms use periods of repetitive task performance to generate sustained functional signal changes. We have developed a technique of imaging the small, transient signal changes that occur after single cognitive events. The technique uses echo-planar imaging at 3 T to generate functional images of the whole brain with a temporal resolution of 3 seconds. It uses a signal averaging technique to create time sweeps of functional activity. After a single cognitive event, widely distributed patterns of brain activation can be detected and their time course measured. This technique enables the individual cognitive tasks that constitute a paradigm to be analyzed separately and compared. We describe the application of this new technique to separate the cognitive elements in a simple "go/no-go" motor paradigm. Comparison of activation patterns during "go" and "no-go" responses reveals hierarchical subdivision of the medial premotor cortex into an anterior region (presupplementary motor area) involved in movement decision making and a posterior region (supplementary motor area proper) directly involved in motor execution.
authors.affiliation: Division of Clinical Neurology, Queens Medical Centre, Nottingham, UK.
authors.forename: M
authors.initials: M
authors.lastname: Humberstone
authors.forename: G V
authors.initials: GV
authors.lastname: Sawle
authors.forename: S
authors.initials: S
authors.lastname: Clare
authors.forename: J
authors.initials: J
authors.lastname: Hykin
authors.forename: R
authors.initials: R
authors.lastname: Coxon
authors.forename: R
authors.initials: R
authors.lastname: Bowtell
authors.forename: I A
authors.initials: IA
authors.lastname: Macdonald
authors.forename: P G
authors.initials: PG
authors.lastname: Morris
mesh_terms: D000328:Adult; D019054:Evoked Potentials, Motor / Q000502:physiology*; D005260:Female; D005625:Frontal Lobe / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009044:Motor Cortex / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology