In quantity discrimination tasks, adults, infants and animals have been sometimes observed to process number only after all continuous variables, such as area or density, have been controlled for. This has been taken as evidence that processing number may be more cognitively demanding than processing continuous variables. We tested this hypothesis…

Categorical perception (CP) is said to occur when a continuum of equally spaced physical changes is perceived as unequally spaced as a function of category membership (Harnad, S. (Ed.) (1987). Psychophysical and cognitive aspects of categorical perception: A critical overview. Cambridge: Cambridge University Press). A common suggestion is that CP…

In previous studies, children disoriented in small enclosures used room shape, but not wall colors, to find hidden objects. Their reorientation was said to depend solely on a "geometric module" informationally encapsulated with respect to color. We argue that previous studies did not fully evaluate children's use of color owing to a bias in the…

Viewing a threatening stimulus can bias visual attention toward that location. Such effects have typically been investigated only in the visual modality, despite the fact that many threatening stimuli are most dangerous when close to or in contact with the body. Recent multisensory research indicates that a neutral visual stimulus, such as a light…

This study demonstrates that non-human primates can categorize the direction of the pitch change of tones in a sequence. Two "Macaca fascicularis" were trained in a positive-reinforcement behavioral paradigm in which they listened to sequences of a variable number of different acoustic items. The training of discriminating pitch direction was…

Compared the performance of children with and without autism in object-based positive and negative priming tasks within a visual search procedure. Found object-based positive and negative priming effects in both groups, with no group differences in the magnitude of the effects. Compared to typically developing children, children with autism were…

Two experiments examined 6-month-olds' ability to discriminate between visual displays of various number of dots varying in size and position, and with controls for other extraneous variables. Findings indicated that infants could discriminate between large sets on the basis of numerosity if they differed by a large ratio (8 versus 16, but not 8…

Two experiments compared 6-month-olds' numerosity discrimination performance on both large numbers and small numbers with both total filled area and total contour length controlled. Results showed that infants succeeded in discriminating 4 from 8 elements, but failed to discriminate 2 from 4 elements, providing evidence for the existence of two…

Familiarized 6- and 8-month-olds with speech sounds from a phonetic continuum, exhibiting a bimodal or unimodal frequency distribution. Found that only infants in the bimodal condition discriminated tokens from the endpoints of the continuum. Results demonstrate that infants are sensitive to the statistical distribution of speech sounds in the…

Presented neonates with lexical and grammatical words prepared from natural maternal speech. Found that neonates could categorically discriminate the sets based on a constellation of perceptual cues that distinguished them. Suggested that this ability to discriminate words on basis of multiple acoustic/phonological cues provides a perceptual base…

To trace how age and language experience shape the discrimination of native and non-native phonetic contrasts, we compared 4-year-olds learning either English or French or both and simultaneous bilingual adults on their ability to discriminate the English /d-[delta]/ contrast. Findings show that the ability to discriminate the native English…

Examined the ability of bilingual college students from Catalonia, Spain to learn a new vowel contrast as indicated by classifying the vowel, discriminating two vowels, and judging its "category-goodness." Found a lack of behavioral plasticity and that early, extensive exposure to a second language was sufficient to attain the…

This brief report attempts to resolve the claim that infants preferentially attend to continuous variables over number [e.g. Psychol. Sci. 10 (1999) 408; Cognit. Psychol.44 (2002) 33] with the finding that when continuous variables are controlled, infants as young as 6-months of age discriminate large numerical values [e.g. Psychol. Sci. 14 (2003)…