title: An fMRI Investigation of Preparatory Set in the Human Cerebral Cortex and Superior Colliculus for Pro- and Anti-Saccades.
abstract: Previous studies have identified several cortical regions that show larger BOLD responses during preparation and execution of anti-saccades than pro-saccades. We confirmed this finding with a greater BOLD response for anti-saccades than pro-saccades during the preparation phase in the FEF, IPS and DLPFC and in the FEF and IPS in the execution phase. We then applied multi-voxel pattern analysis (MVPA) to establish whether different neural populations are involved in the two types of saccade. Pro-saccades and anti-saccades were reliably decoded during saccade execution in all three cortical regions (FEF, DLPFC and IPS) and in IPS during saccade preparation. This indicates neural specialization, for programming the desired response depending on the task rule, in these regions. In a further study tailored for imaging the superior colliculus in the midbrain a similar magnitude BOLD response was observed for pro-saccades and anti-saccades and the two saccade types could not be decoded with MVPA. This was the case both for activity related to the preparation phase and also for that elicited during the execution phase. We conclude that separate cortical neural populations are involved in the task-specific programming of a saccade while in contrast, the SC has a role in response preparation but may be less involved in high-level, task-specific aspects of the control of saccades.
authors.affiliation: Royal Holloway University of London, Egham Hill, Egham, Surrey, TW20 0EX, United Kingdom.
authors.forename: Michele
authors.initials: M
authors.lastname: Furlan
authors.affiliation: Royal Holloway University of London, Egham Hill, Egham, Surrey, TW20 0EX, United Kingdom.
authors.forename: Andrew T
authors.initials: AT
authors.lastname: Smith
authors.affiliation: Royal Holloway University of London, Egham Hill, Egham, Surrey, TW20 0EX, United Kingdom.
authors.forename: Robin
authors.initials: R
authors.lastname: Walker
mesh_terms: D000328:Adult; D002540:Cerebral Cortex / Q000000981:diagnostic imaging / Q000502:physiology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009415:Nerve Net / Q000000981:diagnostic imaging / Q000502:physiology; D012438:Saccades / Q000502:physiology*; D013477:Superior Colliculi / Q000000981:diagnostic imaging / Q000502:physiology; D014796:Visual Perception / Q000502:physiology*