title: Frontal-parietal synchrony in elderly EEG for visual search.
abstract: Aging involves selective changes in attentional control. However, its precise effect on visual attention is difficult to discern from behavioural studies alone. In this paper, we employ a recently developed phase-locking measure of synchrony as an indicator of top-down/bottom-up control of attention to assess attentional control in the elderly. Fourteen participants (63-74 years) searched for a target item (coloured, oriented rectangular bar) among a display set of distractors. For the feature search condition, where none of the distractors shared a feature with the target, search time did not increase with display set size (two, or four items). For the conjunctive search condition, where each distractor shared either a colour or orientation feature with the target, search time increased with display size. Phase-locking analysis revealed a significant increase in high gamma-band (36-56 Hz) synchrony indicating greater bottom-up control for feature than conjunctive search. In view of our earlier study on younger (21-32 years) adults (Phillips and Takeda, 2009), these results suggest that older participants are more likely to use bottom-up control of attention, possibly triggered by their greater susceptibility to attentional capture, than younger participants.
authors.affiliation: Neuroscience Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba Central 2, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 Japan. a.w.keizer@uva.nl
authors.forename: Steven
authors.initials: S
authors.lastname: Phillips
authors.forename: Yuji
authors.initials: Y
authors.lastname: Takeda
mesh_terms: D000367:Age Factors; D000368:Aged; D000375:Aging; D000704:Analysis of Variance; D001288:Attention / Q000502:physiology; D001931:Brain Mapping; D003463:Cues; D004569:Electroencephalography; D005106:Exploratory Behavior / Q000502:physiology*; D005133:Eye Movements / Q000502:physiology; D005260:Female; D005625:Frontal Lobe / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009415:Nerve Net / Q000502:physiology; D009483:Neuropsychological Tests; D009949:Orientation / Q000502:physiology; D010296:Parietal Lobe / Q000502:physiology*; D010775:Photic Stimulation; D012815:Signal Processing, Computer-Assisted; D014796:Visual Perception / Q000502:physiology*