Attentional Modulation and Processing Architecture in Perceptual Categorization

The processing architecture underlying perceptual categorization can be modulated by the spatial arrangement of features. While separable dimensions are typically processed serially when presented in distinct spatial locations, overlapping or spatially adjacent features may allow for parallel processing. This study investigates how spatial proximity influences the deployment of attention and, consequently, the architecture of cognitive processing. We conducted two experiments that systematically varied the spatial separation of two diagnostic features (saturation and orientation) embedded within schematic stimuli. Using the logical rules paradigm and Systems Factorial Technology (SFT), we assessed whether processing was best described by serial, parallel, or mixed-model architectures. Results revealed that increased spatial separation biased processing toward serial architectures, while overlapping and adjacent features led to mixtures of serial and parallel processing. These findings support the notion that attentional allocation is sensitive to spatial layout, and they highlight how perceptual organization constrains the architecture of information processing during categorization. Implications for models of visual attention and perceptual decision-making are discussed.