This paper provides an introduction to mixed-effects models for the analysis of repeated measurement data with subjects and items as crossed random effects. A worked-out example of how to use recent software for mixed-effects modeling is provided. Simulation studies illustrate the advantages offered by mixed-effects analyses compared to traditional analyses based on quasi-F tests, by-subjects analyses, combined by-subjects and by-items analyses, and random regression. Applications and possibilities across a range of domains of inquiry are discussed

Bilinguals have been shown to outperform monolinguals in a variety of tasks that do not tap into linguistic processes. The origin of this bilingual advantage has been questioned in recent years. While some authors argue that the reason behind this apparent advantage is bilinguals' enhanced executive functioning, inhibitory skills and/or monitoring abilities, other authors suggest that the locus of these differences between bilinguals and monolinguals may lie in uncontrolled factors or incorrectly matched samples. In the current study we tested a group of 180 bilingual children and a group of 180 carefully matched monolinguals in a child-friendly version of the ANT task. Following recent evidence from similar studies with children, our results showed no bilingual advantage at all, given that the performance of the two groups in the task and the indices associated with the individual attention networks were highly similar and statistically indistinguishable.

The relationship between semantic and grammatical processing in sentence comprehension was investigated by examining event-related potential (ERP) and event-related power changes in response to semantic and grammatical violations. Sentences with semantic, phrase structure, or number violations and matched controls were presented serially (1.25 words/s) to 20 participants while EEG was recorded. Semantic violations were associated with an N400 effect and a theta band increase in power, while grammatical violations were associated with a P600 effect and an alpha/beta band decrease in power. A quartile analysis showed that for both types of violations, larger average violation effects were associated with lower relative amplitudes of oscillatory activity, implying an inverse relation between ERP amplitude and event-related power magnitude change in sentence processing.

We report two experiments that investigate practice effects on Stroop color-word interference in older and younger adults. Both experiments employed a computerized, single-item version of the Stroop task with a voice response, and both involved practice over hundreds of trials. Both experiments showed generally similar practice patterns, including a practice-related reduction in the size of the color-word interference effect. However, the older group continued to show a larger interference effect throughout practice. These findings indicate that older adults show the same trend in practice-related improvement on the Stroop task as younger adults.As is true for the cognitive literature in general (cf. MacLeod, 1991), the Stroop effect is a mainstay of research on age-related differences in selective attention, automaticity, inhibitory processes, and executive control. A major focus of the aging research has been on the relative size of Stroop interference effects in younger and older adults. The typical finding is that, relative to a baseline condition involving the naming of colors of neutral stimuli (e.g., strings of X's), older adults show a greater increase in reaction time and/or errors in naming of the print colors of incongruent color words than do younger adults (Cohen, Dustman, & Bradford, 1984;Comalli, Wapner, & Werner, 1962;Houx, Jolles, & Vreeling, 1993;Kieley & Hartley, 1997;Li & Bosman, 1996;Spieler, Balota, & Faust, 1996;Vakil, Manovich, Ramati, & Blachstein, 1996; but see Verhaeghen & De Meersman, 1998). Although these data have sometimes been attributed to general slowing effects (Verhaeghen & De Meersman, 1998), others have argued that the larger Stroop effects in older than in younger adults support views proposing age deficits in particular cognitive processes (e.g., the inhibition deficit view of Hasher & Zacks, 1988) or neural mechanisms (e.g., the frontal lobe dysfunction view; Perfect, 1997;Stuss, Eskes, & Foster, 1994;West, 1996). With respect to this last point, there is considerable current interest in relating age differences in the Stroop effect and on other measures of executive function (e.g., task switching; cf. Kramer, Hahn, & Gopher, 1999) to neuroanatomical and neuroimaging findings suggesting that aging particularly affects functions served by prefrontal areas of the brain. For example, a recent fMRI study by Milham et al. (2002) found differences in the patterns of neural activity associated with Stroop performance between younger and older adults, including less extensive activity in the dorsolateral prefrontal cortex in the older group. MacLeod (1991) stressed that the role of practice is critical for understanding the Stroop interference effect and how the Stroop effect can be used to study selective attention. Theoretical accounts of Stroop performance often link interference from incongruent color words to a presumed greater automaticity of (or familiarity with) word reading as compared to color naming. Prolonged practice of color naming should reverse this discr...

Telling time is an exercise in coordinating language production with visual perception. By coupling different ways of saying times with different ways of seeing them, the performance of time-telling can be used to track cognitive transformations from visual to verbal information in connected speech. To accomplish this, we used eyetracking measures along with measures of speech timing during the production of time expressions. Our findings suggest that an effective interface between what has been seen and what is to be said can be constructed within 300 ms. This interface underpins a preverbal plan or message that appears to guide a comparatively slow, strongly incremental formulation of phrases. The results begin to trace the divide between seeing and saying -or thinking and speaking- that must be bridged during the creation of even the most prosaic utterances of a language