Categorical perception effects reflect differences in typicality on within-category trials

Abstract

Many studies have shown better discrimination of two stimuli that cross a category boundary than of two stimuli belonging to the same category. This finding, known as categorical perception, is generally assumed to reflect consistently good performance on cross-category trials, relative to within-category trials. However, Roberson, D., Damjanovic, L., and Pilling, M. (Memory & Cognition, 35, 1814-1829 revealed that performance on withincategory pairs of morphed facial expressions matched performance on cross-category trials when the target was a good exemplar of its category. Here, we investigate the generality of that finding by conducting new analyses of data from a series of studies of categorical perception in facial identity and color domains with speakers of different languages. Consistent with Roberson et al. (2007), the new analyses demonstrate that performance for central targets on within-category trials is as good as performance on crosscategory trials. Participants perform badly on withincategory items only when the target is closer to the category boundary than is the distractor. These results provide no support for the view that categorical perception is associated with increased perceptual sensitivity at category boundaries.

Categorical encoding of color in the brain

“…Also debated is the extent to which color categories affect how color is perceived. Some have argued that color categories affect the cognitive or attentional strategies of perceptual color judgments (7,8), or that color categories affect early stages of color processing even when colors are not attended (9)(10)(11)(12). However, others have argued that noncategorical sensory models of color encoding are sufficient to account for how color is perceived (13).…”

“…The origin and nature of such color categories has been extensively debated across the cognitive sciences (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12). Traditionally, debate has focused on whether color categories are biologically constrained (2,3), or whether they are arbitrary linguistic constructs that arise out of culture and communication (4).…”

Absolute Judgment of Musical Interval Width

“…When a stimulus moves away from a prototype, the difference is easier to detect than an equivalent change in the opposite direction. This asymmetry occurs in multiple domains (Bharucha & Pryor, 1986;Hanley & Roberson, 2011) and has been observed for musical intervals (Schellenberg & Trehub, 1994). In musical terms, a prototype musical sound is considered ''well-tuned,'' and moving away from a prototype represents a change from better tuning to worse tuning.…”

Language and Culture

“…Nonetheless, within-category discrimination improves when the target color is a good exemplar of the color category and the distractor a poor exemplar, compared to the situation in which the target color is a poor exemplar of the category and the distractor a better exemplar (Hanley & Roberson, 2011). This evidence provides further support for the effect language categorization on color perception, suggesting that discriminating colors from different color categories is like discriminating a good exemplar of a category from a distractor color that is at boundary of the color category.…”

“…According to dual system model of language and culture (Regier, Kay, & Khetarpal, 2007;Roberson, in press), the left hemisphere of the brain has Figure 4. A dual system model of language and cognition when the target color is a good exemplar of the color category and the distractor a poor plar, compared to the situation in which the target color is a poor exemplar of the category and the distractor a better exemplar (Hanley & Roberson, 2011). This evidence provides further support for the effect language categorization on color perception, suggesting that discriminating colors from different color categories is like discriminating a good exemplar of a category from a distractor color that is at boundary of the color More important, in a subsequent study, when a verbal interference procedure was introduced to prevent subvocal encoding of the stimuli, the effect of categorical perception of colors on color memory disappeared .…”