72 1024x768 normal 0 false false false en-us x-none ar-sa background : by providing a picture from published articles in a field, bibliometric studies can inform policy-makers in their challenging research funding decisions. in this regard, we applied bibliometric analysis to the iranian pediatrics articles published in pubmed indexed journals between 1975 and 2007. methods : we evaluated all p...

Displays of eight capital letters were presented in a circular arrangement around a central fixation point at tachistoscopic durations. Under different experimental conditions, one or two indicators, presented either 250 msec before, simultaneously with, or after the display, designated the letters that S was to report. The arrangement of conditions permitted inferences as to the order in which...

Information about the order of items in a sequence can be conveyed either spatially or temporally. In the present investigation, we examined whether these different modes of presentation map onto compatible mental representations of serial order. We examined this issue in three immediate serial-recall experiments, in which participants recalled lists of letters in the temporal order in which th...

Dual-task research has revealed a response-selection bottleneck: response selection cannot occur simultaneously in two different tasks, though perceptual processing may overlap response selection (Welford, 1952; Pashler & Johnston, 1989). In serial performance with preview, the same task is performed repeatedly, but stimuli are available well before response. Does the dual-task bottleneck limit...

BACKGROUND The question of how the brain encodes letter position in written words has attracted increasing attention in recent years. A number of models have recently been proposed to accommodate the fact that transposed-letter stimuli like jugde or caniso are perceptually very close to their base words. METHODOLOGY Here we examined how letter position coding is attained in the tactile modali...

Visual word identification requires readers to code the identity and order of the letters in a word and match this code against previously learned codes. Current models of this lexical matching process posit context-specific letter codes in which letter representations are tied to either specific serial positions or specific local contexts (e.g., letter clusters). The spatial coding model descr...

It was suggested that some discrimination tasks (e.g. discrimination between the letters T and L) require serial search by scrutinizing each letter (target) with a small aperture of focal attention. Here we examine the effect of intertarget distance on discrimination performance, using two targets. We find reduction in performance at short distances, in agreement with masking studies, but const...

Four experiments investigated whether a highly salient color singleton can be ignored during serial search. Observers searched for a target letter among nontarget letters and were instructed to ignore an irrelevant, highly salient color singleton that was either compatible or incompatible with the response to the target letter. The results indicate that it was possible to prevent attentional ca...