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An area within the ventral occipitotemporal cortex (vOTC), the "visual word form area" (VWFA), typically exhibits a strongly left-lateralized response to orthographic stimuli in skilled readers. While individual variation in VWFA lateralization has been observed, the behavioral significance of laterality differences remains unclear. Here, we test the hypothesis that differences in VWFA lateralization reflect differing preferences for holistic orthographic analysis. To examine this hypothesis, we implemented a new multivariate method that uses machine learning to assess functional lateralization, along with a traditional univariate lateralization method. We related these neural metrics to behavioral indices of holistic orthographic analysis (inversion sensitivity). The multivariate measure successfully detected the lateralization of orthographic processing in the VWFA, and as hypothesized, predicted behavioral differences in holistic orthographic analysis. An exploratory whole brain analysis identified further regions with a relationship between inversion sensitivity and lateralization: one near the junction of the inferior frontal and precentral sulci, and another along the superior temporal gyrus. We conclude that proficient native readers of English exhibit differences in cortical lateralization of the VWFA that have significant implications for reading behavior., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Quitting smoking is the single best change in behavior that smokers can make to improve their health and extend their lives. Although most smokers express a strong desire to stop using cigarettes, the vast majority of quit attempts end in relapse. Relapse is particularly likely when smokers encounter cigarette cues. A striking number of relapses occur very quickly, with many occurring within as little as 24h. Characterizing what distinguishes successful quit attempts from unsuccessful ones, particularly just after cessation is initiated, is a research priority. We addressed this significant issue by examining the association between functional connectivity during cigarette cue exposure and smoking behavior during the first 24h of a quit attempt. Functional MRI was used to measure brain activity during cue exposure in nicotine-deprived daily smokers during the first day of a quit attempt. Participants were then given the opportunity to smoke. Using data collected in two parent studies, we identified a subset of participants who chose to smoke and a matched subset who declined (n=38). Smokers who were able to resist smoking displayed significant functional connectivity between the left anterior insula and the dorsolateral prefrontal cortex, whereas there was no such connectivity for those who chose to smoke. Notably, there were no differences in mean levels of activation in brain regions of interest, underscoring the importance of assessing interregional connectivity when investigating the links between cue-related neural responses and overt behavior. To our knowledge, this is the first study to link patterns of functional connectivity and actual cigarette use during the pivotal first hours of attempt to change smoking behavior., (Copyright © 2016 Elsevier Inc. All rights reserved.)

The striatum has been shown to be a key region in the processing of reward-related information. The head of the caudate nucleus has been implicated in processing performance feedback, or in other words, information about the outcomes of one's actions. However, feedback provides multiple types of information, and it is not clear which of these types of information drive a caudate response. We sought to determine whether the signal in the caudate differed when feedback was informative but only arbitrarily related to performance versus when it provided information about goal achievement. To do this, we used functional magnetic resonance imaging (fMRI) to examine caudate activation during a feedback-based paired associate word-learning task. During an initial round of 60 distinct trials, participants chose one of two responses on each trial and received feedback about whether their responses were correct. On the subsequent two rounds, the 60 trials were repeated and participants chose their responses based on their memory of the correct answer. The caudate nuclei were strongly engaged only during the second two rounds, when feedback reflected the accuracy of memory. These results support the idea that feedback-based caudate activation is context dependent: the caudate can be engaged in feedback-based declarative memory tasks, but it is more strongly engaged when feedback is "earned" by performance than when it is informative but not tied to goal achievement.

Neuroimaging studies of working memory have revealed two sites in the left supramarginal gyrus that may support the short-term storage of phonological information. Activation in the left dorsal aspect of the inferior parietal cortex (DIPC) has been observed in contrasts of working memory load, whereas activation in the ventral aspect of the inferior parietal cortex (VIPC) has been found primarily in contrast of information type (verbal vs. nonverbal). Our goal was to determine whether these two areas are functionally distinct or if instead they are part of a homogeneous region with large variations in the focus of peak activity. Toward this end, we used fMRI to assess the neural response in two working memory tasks (N-back and item recognition) in which we also manipulated memory load and the type of information to be recalled (verbal vs. nonverbal). We found both DIPC and VIPC activation in the same group of subjects and further demonstrated that they have differential sensitivity to our experimental factors. Only the DIPC showed robust load effects, whereas only the VIPC showed reliable effects of information type. These results help to account for the differences observed in between-subject comparisons, and they indicate that the two regions are functionally dissociable. In contrast to the DIPC, activity of the VIPC was also recruited in the fixation and low-load conditions, a surprising result that has not been fully explored in prior studies. Despite their distinctive patterns of performance, neither of these regions displayed a pattern of activity that entirely corresponds to common assumptions of a dedicated phonological short-term store (STS). Instead, we hypothesize that the DIPC may support domain-general executive processes, while the VIPC may support phonological encoding-recoding processes central to a variety of language tasks.

Working memory, as defined by Baddeley and Hitch, is an interactive set of cognitive processes responsible for holding information online and available for analysis. Part of that system is a specialized subsystem devoted to maintaining verbal information; the verbal "slave" subsystem has as a core component a phonological store. For many years, the anatomical locus of the phonological store has been thought to be in the supramarginal and angular gyri of the speech dominant hemisphere, and functional neuroimaging studies provide broad support for this localization. However, a finer grained analysis of published experiments reveals two possible foci for the phonological store within the parietal lobe, neither of which has a pattern of functional activation that is fully consistent with the Baddeley and Hitch model. The purpose of the present paper is to review several studies relevant to the question of the localization of the phonological store and to suggest possible reasons the results are discrepant., (Copyright 1999 Academic Press.)