Selective attention and interference from the irrelevant domain are frequently neglected factors in working memory experiments. Here identical stimuli were employed in n-back tasks under spatial and verbal task instructions to test whether information in the irrelevant domain was really irrelevant. The results reveal interference from the irrelevant domain in the replacement sub-process of the ...

This study examined whether there are neural markers of individual differences in working memory (WM) capacity and whether these differences are only manifest when performing a demanding WM task or at all levels of difficulty. Each subject's WM capacity was estimated using a modified digit span task prior to participation in an N-back task that varied difficulty from 1- to 4-back. While perform...

OBJECTIVE Fragile X syndrome is a neurogenetic disorder that is the most common known heritable cause of neurodevelopmental disability. This study examined the neural substrates of working memory in female subjects with fragile X syndrome. Possible correlations among behavioral measures, brain activation, and the FMR1 gene product (FMRP expression), as well as between IQ and behavioral measures...

Performance on perceptual-motor (PM) tasks should not be affected by cognitive workload (CW). Subjects performed a novel task that combined a ”recall” version of the n-back task and a PM distractor task. Subjects’ performance was significantly worse on the PM task when CW was increased. As CW was manipulated, the perceptual and motor requirements of both the n-back task and the PM task remained...

Despite its frequent use, much is unknown about how the nback task is performed and how it relates to working memory. We conducted a detailed analysis of the accuracy and reaction time data from a 4-back version of the task and compared the results with previous results from an adaptive training version of the task. The experiment was also designed to test the novel predictions of a computation...

We report a vibrotactile version of the common n-back task used to study working memory. Subjects wore vibrotactile stimulators on three fingers of one hand, and they responded by pressing a button with the other hand whenever the current finger matched the one stimulated n items back. Experiment 1 showed a steep decline in performance as n increased from 1 to 3; each additional level ofn decre...

The supramarginal gyrus (SMG) is activated for phonological processing during both language and verbal working memory tasks. Using rTMS, we investigated whether the contribution of the SMG to phonological processing is domain specific (specific to phonology) or more domain general (specific to verbal working memory). A measure of phonological complexity was developed based on sonority differenc...