Rod-isolation techniques show that light-adapted human rods detect flicker frequencies as high as 28 hertz, and that the function relating rod critical flicker frequency to stimulus intensity contains two distinct branches. (MLH)

Four experiments examined the ability of infants to form categorical representations for the spatial relations "above" and "below." Found that three- and four-month-olds could form categorical representations for above and below when a diamond-shape was presented above or below a horizontal bar but could not do so when a number…

A visual discrimination task was used to measure concentration among 43 members of Swiss national orienteering teams. Subjects were above average in the number of target objects dealt with and in duration of continuous concentration. For females only, ranking in orienteering performance was related to quality of concentration (ratio of correct to…

In 2 experiments, 9- and 12-month-old infants were shown pictures of males and females with a female or male voice presented simultaneously. Found that infants spent more time looking at pictures of females presented with a female voice than at other stimuli pictures. (BC)

The authors used visual search tasks in which components of the classic flanker task (B. A. Eriksen & C. W. Eriksen, 1974) were introduced. In several experiments the authors obtained evidence of parallel search for a target among distractor elements. Therefore, 2-stage models of visual search predict no effect of the identity of those…

In visual search tasks, if a set of items is presented for 1 s before another set of new items (containing the target) is added, search can be restricted to the new set. The process that eliminates old items from search is visual marking. This study investigates the kind of memory that distinguishes the old items from the new items during search.…

Data are reported from 3,213 research eyewitnesses confirming that accurate eyewitness identifications from lineups are made faster than are inaccurate identifications. However, consistent with predictions from the recognition and search literatures, the authors did not find support for the "10-12-s rule" in which lineup identifications faster…

Confidence-accuracy (CA) calibration was examined for absolute and relative face recognition judgments as well as for recognition judgments from groups of stimuli presented simultaneously or sequentially (i.e., simultaneous or sequential mini-lineups). When the effect of difficulty was controlled, absolute and relative judgments produced…

Methods to automatically convert graphics into tactile representations have been recently investigated, creating either raised-line or relief images. In particular, we briefly review one raised-line method where important features are emphasized. This paper focuses primarily on the effects of such emphasis and on comparing both raised-line and…

The purpose of this study was to examine the progress monitoring and screening accuracy for a set of curriculum-based measures (CBM) of early mathematics skills. Measures included counting objects, selecting numbers, naming numbers, counting, and visual discrimination. Measures were designed to be administered with preschoolers in a short period…

Attention-deficit/hyperactivity disorder (ADHD) is associated with unexplained impairments on speeded naming of coloured stimuli. These deficits may reflect hypofunctioning retinal dopaminergic mechanisms impairing particularly blue-yellow colour discrimination. Colour perception and rapid colour naming ability were investigated in 14 children…

We investigated how within-stimulus heterogeneity affects the ability of rhesus monkeys to order pairs of the numerosities 1 through 9. Two rhesus monkeys were tested in a touch screen task where the variability of elements within each visual array was systematically varied by allowing elements to vary in color, size, shape, or any combination of…

Object substitution masking (OSM) is said to occur when a perceptual object is hypothesized that is mismatched by subsequent sensory evidence, leading to a new hypothesized object being substituted for the first. For example, when a brief target is accompanied by a longer lasting display of nonoverlapping mask elements, reporting of target…

In this study, we investigated relations between infants' understanding of intentional actions and measures of social responsiveness during a transitional period, 9- to 11-months. Infants (N = 52) were tested in visual habituation paradigms tapping their understanding of the relation between a person and the object of her attention. Measures of…

Objective: To examine the ability of the flicker task to demonstrate greater utility in discriminating performance in young adults with and without ADHD compared to the Conners' CPT (CCPT). Method: Flicker task and CCPT performance were compared between an ADHD (n = 28) and control (n = 30) group of college students. Results: This study replicated…