The effects of attention and object configuration on the neural responses to short-lag visual image repetition
were investigated with fMRI. Attention to one of two object images in a prime display was cued spatially. The
images were either intact or split vertically; a manipulation that negates the influence of view-based
representations. A subsequent single intact probe image was named covertly. Behavioural priming observed
as faster button presses was found for attended primes in both intact and split configurations, but only for
uncued primes in the intact configuration. In a voxel-wise analysis, fMRI repetition suppression (RS) was
observed in a left mid-fusiform region for attended primes, both intact and split, whilst a right intraparietal
region showed repetition enhancement (RE) for intact primes, regardless of attention. In a factorial analysis
across regions of interest (ROIs) defined from independent localiser contrasts, RS for attended objects in the
ventral stream was significantly left-lateralised, whilst repetition effects in ventral and dorsal ROIs correlated
with the amount of priming in specific conditions. These fMRI results extend hybrid theories of object
recognition, implicating left ventral stream regions in analytic processing (requiring attention), consistent
with prior hypotheses about hemispheric specialisation, and implicating dorsal stream regions in holistic
processing (independent of attention)