title: Early visual cortex reflects initiation and maintenance of task set.
abstract: The human brain is able to process information flexibly, depending on a person's task. The mechanisms underlying this ability to initiate and maintain a task set are not well understood, but they are important for understanding the flexibility of human behavior and developing therapies for disorders involving attention. Here we investigate the differential roles of early visual cortical areas in initiating and maintaining a task set. Using functional Magnetic Resonance Imaging (fMRI), we characterized three different components of task set-related, but trial-independent activity in retinotopically mapped areas of early visual cortex, while human participants performed attention demanding visual or auditory tasks. These trial-independent effects reflected: (1) maintenance of attention over a long duration, (2) orienting to a cue, and (3) initiation of a task set. Participants performed tasks that differed in the modality of stimulus to be attended (auditory or visual) and in whether there was a simultaneous distractor (auditory only, visual only, or simultaneous auditory and visual). We found that patterns of trial-independent activity in early visual areas (V1, V2, V3, hV4) depend on attended modality, but not on stimuli. Further, different early visual areas play distinct roles in the initiation of a task set. In addition, activity associated with maintaining a task set tracks with a participant's behavior. These results show that trial-independent activity in early visual cortex reflects initiation and maintenance of a person's task set.
authors.affiliation: Neurobiology Department, University of Alabama at Birmingham, CIRC 111D, 1530 3(RD) Avenue South, Birmingham, AL 35294, USA. Electronic address: elkhital@uab.edu.
authors.forename: Abdurahman S
authors.initials: AS
authors.lastname: Elkhetali
authors.affiliation: Neurobiology Department, University of Alabama at Birmingham, CIRC 111D, 1530 3(RD) Avenue South, Birmingham, AL 35294, USA. Electronic address: rjvaden@uab.edu.
authors.forename: Ryan J
authors.initials: RJ
authors.lastname: Vaden
authors.affiliation: Biomedical Engineering, University of Alabama at Birmingham, 1530 3(RD) Avenue South, Birmingham, AL 35294, USA. Electronic address: spool626@uab.edu.
authors.forename: Sean M
authors.initials: SM
authors.lastname: Pool
authors.affiliation: Neurobiology Department, University of Alabama at Birmingham, CIRC 111D, 1530 3(RD) Avenue South, Birmingham, AL 35294, USA; Biomedical Engineering, University of Alabama at Birmingham, 1530 3(RD) Avenue South, Birmingham, AL 35294, USA; Psychology Department, University of Alabama at Birmingham, 1530 3(RD) Avenue South, Birmingham, AL 35294, USA. Electronic address: kmv@uab.edu.
authors.forename: Kristina M
authors.initials: KM
authors.lastname: Visscher
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D001288:Attention / Q000502:physiology; D001307:Auditory Perception / Q000502:physiology; D003071:Cognition / Q000502:physiology; D003463:Cues; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D010775:Photic Stimulation; D011597:Psychomotor Performance / Q000502:physiology*; D012160:Retina / Q000502:physiology; D012684:Sensory Thresholds; D014793:Visual Cortex / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology; D055815:Young Adult
keywords: Attentional set; Cognitive control; Intrinsic activity; Task set; Trial-independent; Visual cortex