Williams Syndrome (WS) is a developmental disorder typified by deficits in visuospatial cognition. To understand the nature of this deficit, we characterized how people with WS perceive visual orientation, a fundamental ability related to object identification. We compared WS participants to typically developing children (3-6 years of age) and…

In 2 experiments, the interplay of action perception and action production was investigated in 6-month-old infants. In Experiment 1, infants received 2 versions of a means-end task in counterbalanced order. In the action perception version, a preferential looking paradigm in which infants were shown an actor performing means-end behavior with an…

Five experiments examined 79 newborns' ability to discriminate and categorize a spatial relation, defined by the left-right spatial position of a blinking object-target with respect to a vertical landmark-bar. Three-day-old infants discriminated the up versus low position of an object located on the same side of the landmark-bar (Experiment 1) and…

Audio-visual stimulus pairs presented at various relative delays, are commonly judged as being "synchronous" over a range of delays from about -50 ms (audio leading) to +150 ms (video leading). The center of this range is an estimate of the point of subjective simultaneity (PSS). The judgment boundaries, where "synchronous" judgments yield to a…

Can infants use interposition and line junction cues to infer three-dimensional (3D) structure? Previous work has shown that in a task that required 4-month-olds to discriminate between static two-dimensional (2D) pictures of possible and impossible cubes, infants exhibited a spontaneous preference for displays of the impossible cube but left open…

Both classical and recent reports suggest a right-hemisphere superiority for color discrimination. Testing highly-trained normal subjects and taking care to eliminate asymmetries from the testing situation, we found no significant differences between left and right hemifields or between upper and lower hemifields. This was the case for both of the…

Previous studies have shown that as a group 6-month-old infants successfully discriminate numerical changes when the values differ by at least a 1:2 ratio but fail at a 2:3 ratio (e.g. 8 vs. 16 but not 8 vs. 12). However, no studies have yet examined individual differences in number discrimination in infancy. Using a novel numerical change…

Plaut and McClelland (2010) and Quian Quiroga and Kreiman both challenged my characterization of localist and distributed representations. They also challenged the biological plausibility of grandmother cells on conceptual and empirical grounds. This reply addresses these issues in turn. The premise of my argument is that grandmother cells in…

Two experiments examined the effects of multimodal presentation and stimulus familiarity on auditory and visual processing. In Experiment 1, 10-month-olds were habituated to either an auditory stimulus, a visual stimulus, or an auditory-visual multimodal stimulus. Processing time was assessed during the habituation phase, and discrimination of…

Recent evidence from adult pronoun comprehension suggests that semantic factors such as verb transitivity affect referent salience and thereby anaphora resolution. We tested whether the same semantic factors influence pronoun comprehension in young children. In a visual world study, 3-year-olds heard stories that began with a sentence containing…

In Experiment 1, "more" and "less" relations were trained for arbitrary Stimuli A1 and A2 with 3 children with autism. The following conditional discriminations were then trained: A1-B1, A2-B2, B1-C1, B2-C2. In subsequent tests, participants showed derived more-less mands (mand with C1 for more and mand with C2 for less). A training procedure…

We [Lazareva, O. F., Freiburger, K. L., & Wasserman, E. A. (2004). "Pigeons concurrently categorize photographs at both basic and superordinate levels." "Psychonomic Bulletin and Review," 11, 1111-1117] previously trained four pigeons to classify color photographs into their basic-level categories (cars, chairs, flowers, or people) or into their…

In two experiments children with autism and two groups of controls matched for either chronological or non-verbal mental age were tested on tasks of colour discrimination and memory. The results from experiment 1 showed significantly poorer colour discrimination in children with autism in comparison to typically developing chronological age…

There is evidence that, from an early age, humans are sensitive to spatial information such as simple landmarks and the size of objects. This study concerns the ability to represent a particular kind of spatial information, namely, the "geometry" of an enclosed layout--an ability present in older children, adults, and nonhuman animals (e.g.,…

Features from stimuli presented at a high rate in a single spatial position (Rapid Serial Visual Presentation, RSVP) can migrate forming a wrong combination or illusory conjunction. Several serial and parallel models have been proposed to explain the generation of this type of errors. The behavioral results fit better the two-stage parallel model…