Top-down engagement modulates the neural expressions of visual expertise.
Perceptual expertise is traditionally associated with enhanced brain activity in response to objects of expertise in category-selective visual cortex, primarily face-selective regions. We reevaluated this view by investigating whether the brain activity associated with expertise in object recognition is limited to category-selective cortex and specifically whether the extent of expertise-related activity manifests automatically or whether it can be top-down modulated. We conducted 2 functional magnetic resonance imaging studies comparing changes in hemodynamic activity associated with car expertise in a conventional 1-back task (Experiment 1) and when the task relevance of cars was explicitly manipulated (Experiment 2). Whole-brain analysis unveiled extensive expertise-related activity throughout the visual cortex, starting as early as V1 and extending into nonvisual areas. However, when the cars were task irrelevant, the expertise-related activity drastically diminished, indeed, becoming similar to the activity elicited by cars in novices. We suggest that expertise entails voluntary top-down engagement of multiple neural networks in addition to stimulus-driven activation associated with perceptual mechanisms.
Department of Psychology, Hebrew University of Jerusalem 91905, Jerusalem, Israel. assaf.harel@nih.gov
Assaf
A
Harel
Sharon
S
Gilaie-Dotan
Rafael
R
Malach
Shlomo
S
Bentin
D000328:Adult; D001334:Automobile Driving; D001921:Brain / Q000098:blood supply* / Q000502:physiology*; D001931:Brain Mapping; D004192:Discrimination, Psychological / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D010100:Oxygen / Q000097:blood; D010775:Photic Stimulation / Q000379:methods; D011361:Professional Competence; D011597:Psychomotor Performance / Q000502:physiology; D021641:Recognition, Psychology / Q000502:physiology*; D013997:Time Factors; D014795:Visual Pathways / Q000098:blood supply / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*; D055815:Young Adult
D010100:Oxygen