Journal Article


Mark A Bellgrove
Redmond G O'Connell
Simon P Kelly
Gerard M Loughnane
Daniel P Newman



future evolution processes detection psychology neural mechanisms motion cognitive psychology

Visuospatial Asymmetries Arise from Differences in the Onset Time of Perceptual Evidence Accumulation (2017)

Abstract Healthy subjects tend to exhibit a bias of visual attention whereby left hemifield stimuli are processed more quickly and accurately than stimuli appearing in the right hemifield. It has long been held that this phenomenon arises from the dominant role of the right cerebral hemisphere in regulating attention. However, methods that would enable more precise understanding of the mechanisms underpinning visuospatial bias have remained elusive. We sought to finely trace the temporal evolution of spatial biases by leveraging a novel bilateral dot motion detection paradigm. In combination with electroencephalography, this paradigm enables researchers to isolate discrete neural signals reflecting the key neural processes needed for making these detection decisions. These include signals for spatial attention, early target selection, evidence accumulation, and motor preparation. Using this method, we established that three key neural markers accounted for unique between-subject variation in visuospatial bias: hemispheric asymmetry in posterior α power measured before target onset, which is related to the distribution of preparatory attention across the visual field; asymmetry in the peak latency of the early N2c target-selection signal; and, finally, asymmetry in the onset time of the subsequent neural evidence-accumulation process with earlier onsets for left hemifield targets. Our development of a single paradigm to dissociate distinct processing components that track the temporal evolution of spatial biases not only advances our understanding of the neural mechanisms underpinning normal visuospatial attention bias, but may also in the future aid differential diagnoses in disorders of spatial attention.
Collections Ireland -> National College Ireland -> Status = Published
Ireland -> National College Ireland -> Subject = B Philosophy. Psychology. Religion: Psychology: Cognitive psychology
Ireland -> National College Ireland -> Type = Article
Ireland -> National College Ireland -> Subject = B Philosophy. Psychology. Religion: Psychology

Full list of authors on original publication

Mark A Bellgrove, Redmond G O'Connell, Simon P Kelly, Gerard M Loughnane, Daniel P Newman

Experts in our system

Mark A. Bellgrove
Trinity College Dublin
Total Publications: 39
Redmond G O'Connell
Trinity College Dublin
Total Publications: 59
Simon P Kelly
University College Dublin
Total Publications: 48
Gerard M Loughnane
National College Ireland
Total Publications: 17
Daniel P Newman
National College Ireland
Total Publications: 9