Imaging studies of conscious perception using techniques such as masking often show increased neural responses in object processing regions of the brain, and accompany increased awareness of the stimulus. Imaging studies of the attentional blink, an effect where conscious awareness of the stimulus is suppressed through reduction of attentional resources, has tended to show the opposite neural response. This study examines changes in stimulus parameters such that either attention or perceptual information is limited. Findings show that under conditions of limited attention but reduced perception the BOLD response reveals increased activity when the stimulus cannot be reported; however, under conditions of reduced perception but normal attention, more activity is revealed on trials when the stimulus can be reported.
aCentre for Cognitive Neuroscience, University of Wales, Bangor
bMagnetic Resonance & Image Analysis Centre (MARIARC), University of Liverpool, Liverpool, UK
Correspondence to Dr Stephen J. Johnston, Centre for Cognitive Neuroscience, University of Wales, Brigantia Building, Penrallt Road, Bangor, Gwynedd, LL572AS, UK
Tel: +44 1248 382211; e-mail: firstname.lastname@example.org
Received 3 May 2007; accepted 30 May 2007