Independent spatiotemporal effects of spatial attention and background clutter on human object location representations

• Published in: NeuroImage (Orlando, Fla.) Fla.), 2023-05, Vol.272, p.120053-120053, Article 120053
• Main Authors: Graumann, Monika, Wallenwein, Lara A., Cichy, Radoslaw M.
• Format: Article
• Language: English
• Subjects: Attention; Cognitive ability; Decoding; EEG; Experiments; fMRI; Functional magnetic resonance imaging; Humans; Hypotheses; Information processing; Localization; Magnetic Resonance Imaging; Multivariate pattern analysis; Object recognition; Pattern Recognition, Visual; Visual Cortex; Visual Perception
• ISSN: 1053-8119; 1095-9572
• DOI: 10.1016/j.neuroimage.2023.120053

•Attention modulates object location representations during late processing stages.•Clutter in an object's background did not affect the processing stage of attention.•EEG revealed attentional modulation in a late in time window (>150 ms).•fMRI shows the locus to be in higher level ventral stream areas. Spatial attention helps us to efficiently localize objects in cluttered environments. However, the processing stage at which spatial attention modulates object location representations remains unclear. Here we investigated this question identifying processing stages in time and space in an EEG and fMRI experiment respectively. As both object location representations and attentional effects have been shown to depend on the background on which objects appear, we included object background as an experimental factor. During the experiments, human participants viewed images of objects appearing in different locations on blank or cluttered backgrounds while either performing a task on fixation or on the periphery to direct their covert spatial attention away or towards the objects. We used multivariate classification to assess object location information. Consistent across the EEG and fMRI experiment, we show that spatial attention modulated location representations during late processing stages (>150 ms, in middle and high ventral visual stream areas) independent of background condition. Our results clarify the processing stage at which attention modulates object location representations in the ventral visual stream and show that attentional modulation is a cognitive process separate from recurrent processes related to the processing of objects on cluttered backgrounds.