Adaptive modulation of color salience contingent upon global form coding and task relevance

Abstract

Extensive research on local color aftereffects has revealed perceptual consequences of opponent color coding in the retina and the LGN, and of orientation-and/or spatial-frequency-contingent color coding in early cortical visual areas (e.g., V1 and V2). Here, we report a color aftereffect that depends crucially on global-form-contingent color processing. Brief viewing of colored items (passively viewed, ignored, or attended) reduced the salience of the previewed color in a subsequent task of color-based visual search. This color-salience aftereffect was relatively insensitive to variations (between color preview and search) in local image features, but was substantially affected by changes in global configuration (e.g. the presence or absence of perceptual unitization); the global-form dependence of the aftereffect was also modulated by task demands. The overall results suggest that (1) color salience is adaptively modulated (from fixation to fixation), drawing attention to a new color in visual-search contexts, and (2) these modulations seem to be mediated by global-form-and-color-selective neural processing in mid to late stages of the ventral visual pathway (e.g., V4 and IT), in combination with task-dependent feedback from higher cortical areas (e.g., prefrontal cortex).

Intertrial inhibition of focused attention in pop-out search

“…In other words, selective attention is required for negative priming to take place. In contrast, previous studies Ariga, Lleras, & Kawahara, 2004;Goolsby et al, 2005) have shown that selective attention is not required for the DPE to occur. For example, Ariga et al showed that a DPE could be observed even when the target-present display contained only one item.…”

“…Similarly, Goolsby et al (2005), using the same color stimuli used in the present study, also showed a dissociation between these two effects by showing that priming of pop-out was due to attention-based color segmentation (which occurs when there is no pop-out item on the preceding trial but the attended/ignored color segmentation is repeated between trials), whereas the DPE was due to processing of uniformly colored items. Thus, the DPE can take place in the absence of priming of pop-out.…”

“…For instance, imagine a trial with a display of six stimuli, three red and three green. If participants are directed to attend to the red items, and on the subsequent trial a red pop-out target appears within a set of green distractors, a positive bias to attend to the red target is observed in comparison with a trial in which the target is a green pop-out item among a set of red distractors (Goolsby, Grabowecky, & Suzuki, 2005). In other words, priming of pop-out seems to reflect a positive attentional bias toward a previously attended color when this color is repeatedly presented in the context of the same distractor color.…”

“…Goolsby and Suzuki (2001a; see also Goolsby et al, 2005) and used a modified version of Maljkovic and Nakayama's (1994) methodology in which both target-present and target-absent trials were intermixed. Target-present trials consisted of conventional pop-out search displays-one color-oddball item (the popout target) among two items of a second color.…”

Exploring the contributions of spatial and non-spatial working memory to priming of pop-out

“…The DPE reflects a tendency to be much slower and less accurate to select a target on a target-present trial (e.g., a red oddball item) when its target-defining characteristic (red) was associated with the absence of targets in the preceding target-absent trial (i.e., when all items in the preceding trial were red). See Goolsby, Grabowecky, and Suzuki (2005) and Lleras, Kawahara, Wan, and Ariga (2008). The effect is observed in temporal tasks, as well (Lleras, Kawahara, & Levinthal, 2009), and transfers across spatial and temporal tasks (Levinthal & Lleras, 2008).…”