This is a repository copy of Complete revascularization with multivessel PCI for myocardial infarction.

Abstract& We investigated the hypothesis that increased prefrontal activations in older adults are compensatory for decreases in medial-temporal activations that occur with age.

IntroductionPosttraumatic stress disorder (PTSD) is a debilitating psychiatric disorder characterized by symptoms of re-experiencing, hyperarousal, emotional numbing and avoidance; 1 however, exact brain mechanisms involved in the generation of PTSD symptoms or in PTSD pathophysiology have yet to be elucidated. Converging neuroimaging research points to a potentially critical role for disrupted emotion neurocircuitry in individuals with PTSD, and whereas many studies have delineated patterns of activations during face viewing or symptom provocation (for a review, see Shin and Liberzon 2 ), relatively few have examined patterns of connectivity in the brains of patients with PTSD at rest, a potentially powerful method for illuminating brain network structure. 3,4 Most PTSD neuroimaging studies to date have described abnormalities in emotion-generation regions, such as the amygdala or insula, and emotion-regulation regions, including the anterior cingulate cortex (ACC) and medial prefrontal cortex (mPFC). This is consistent with the known role of the amygdala as a key region in threat detection, 5 fear conditioning 6 and emotional salience, 7 and of the mPFC as a modulatory region interconnected with limbic structures 8 and involved in emotion regulation.9 Taken together, functional magnetic resonance imaging (fMRI) studies of individuals with PTSD suggest patterns of hyperactivation of the amygdala and insula to emotion-related stimuli and corresponding hypoactivation of ventromedial prefrontal and rostral anterior cingulate cortices.2 This pattern of amygdala hyperactivity and mPFC hypoactivity was recently confirmed by a meta-analysis of 15 PTSD neuroimaging studies 10 and is generally understood to reflect a lack of regulatory control over emotion in individuals with PTSD.Studies of functional connectivity, however, can provide additional and potentially more direct information about regu latory relationships between the mPFC and amygdala. The amygdala has tight structural connections and reciprocal feedback loops with the mPFC and orbitofrontal cortex 11 as well as with the dorsolateral PFC 12 and ACC. 13 As amygdala Background: Converging neuroimaging research suggests altered emotion neurocircuitry in individuals with posttraumatic stress disorder (PTSD). Emotion activation studies in these individuals have shown hyperactivation in emotion-related regions, including the amygdala and insula, and hypoactivation in emotion-regulation regions, including the medial prefrontal cortex (mPFC) and anterior cingulate cortex (ACC). However, few studies have examined patterns of connectivity at rest in individuals with PTSD, a potentially powerful method for illuminating brain network structure. Methods: Using the amygdala as a seed region, we measured resting-state brain connectivity using 3 T functional magnetic resonance imaging in returning male veterans with PTSD and combat controls without PTSD. Results: Fifteen veterans with PTSD and 14 combat controls enrolled in our study. Compared with controls, veterans with ...

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The cerebellum plays a role in a wide variety of complex behaviors. In order to better understand the role of the cerebellum in human behavior, it is important to know how this structure interacts with cortical and other subcortical regions of the brain. To date, several studies have investigated the cerebellum using resting-state functional connectivity magnetic resonance imaging (fcMRI; Krienen and Buckner, 2009; O'Reilly et al., 2010; Buckner et al., 2011). However, none of this work has taken an anatomically-driven lobular approach. Furthermore, though detailed maps of cerebral cortex and cerebellum networks have been proposed using different network solutions based on the cerebral cortex (Buckner et al., 2011), it remains unknown whether or not an anatomical lobular breakdown best encompasses the networks of the cerebellum. Here, we used fcMRI to create an anatomically-driven connectivity atlas of the cerebellar lobules. Timecourses were extracted from the lobules of the right hemisphere and vermis. We found distinct networks for the individual lobules with a clear division into “motor” and “non-motor” regions. We also used a self-organizing map (SOM) algorithm to parcellate the cerebellum. This allowed us to investigate redundancy and independence of the anatomically identified cerebellar networks. We found that while anatomical boundaries in the anterior cerebellum provide functional subdivisions of a larger motor grouping defined using our SOM algorithm, in the posterior cerebellum, the lobules were made up of sub-regions associated with distinct functional networks. Together, our results indicate that the lobular boundaries of the human cerebellum are not necessarily indicative of functional boundaries, though anatomical divisions can be useful. Additionally, driving the analyses from the cerebellum is key to determining the complete picture of functional connectivity within the structure.