A Neural Decomposition of Visual Search Using Voxel-based Morphometry

Research output: Contribution to journalArticle

Authors

Colleges, School and Institutes

External organisations

  • University of Oxford

Abstract

The ability to search efficiently for visual targets among distractors can break down after a variety of brain lesions, but the specific processes affected by the lesions are unclear. We examined search over space (conjunction search) and over time plus space (preview search) in a consecutive series of patients with acquired brain lesions. We also assessed performance on standard neuropsychological measures of visuospatial short-term memory (Corsi Block), sustained attention and memory updating (the contrast between forward and backward digit span), and visual neglect. Voxel-based morphometry analyses revealed regions in the occipital (middle occipital gyrus), posterior parietal (angular gyrus), and temporal cortices (superior and middle temporal gyri extending to the insula), along with underlying white matter pathways, associated with poor search. Going beyond standard voxel-based morphometry analyses, we then report correlation measures of structural damage in these regions and the independent neuropsychological measures of other cognitive functions. We find distinct patterns of correlation in areas linked to poor search, suggesting that the areas play functionally different roles in search. We conclude that neuropsychological disorders of search can be linked to necessary and distinct cognitive functions, according to the site of lesion.

Details

Original languageEnglish
Pages (from-to)1854-1869
Number of pages16
JournalJournal of Cognitive Neuroscience
Volume27
Issue number9
Publication statusPublished - 31 Jul 2015

Keywords

  • Adult, Aged, Aged, 80 and over, Attention, Brain, Brain Mapping, Executive Function, Female, Humans, Magnetic Resonance Imaging, Male, Memory, Short-Term, Middle Aged, Neuropsychological Tests, Perceptual Disorders, Reaction Time, Signal Processing, Computer-Assisted, Space Perception, Time Perception, Journal Article, Research Support, Non-U.S. Gov't