Improved data acquisition and processing strategies for blood oxygenatlon level-dependent (BOlO)-conlrast funcllona1 magnetie resonaneo imaging (fMRI), wllich enhance the functional eontrast-to-nolse ratio (CNR) by sampllng multiple echo limes In a single shot, are descrlbed. The dependence of Ihe CNR on Ti, Ihe image encoding time, and Ihe number of samplod oeho titnes are Investigated for exponentia1 fitting, echo summation, welghled echo summation, and averaglng of corrolalion maps oblainod at different echo limes. The mothod is validated In vlvo using visual stimulation and turbo proton echoplanar speelroseopie imaging (turbo-PEPSI), a new single-shot multi-slice MR spoclroscoplc Imaging teehnlque, whlch acqulres up 10 12 consocutive ochoplanar images wlth echo limes ranging from 1210213 msec. Quantitative Ti-mapplng slgnificanUy increasos Ihe measured extent of aetivatJon and the mean correlalion coefficient compared wilh convenlional echoplanar imaging. The sensltlvity gain with echo summation, wllicll is compulationally efficiet:'lt provides similar sensitivity as fitting. For all data processing methods sensltivlty is optimum wh on echo limes IIp 10 3.2 T 2 are sampled. This molhodology has implications for comparing functional sonsitivity at different magnetie field strengths and between braln regions with different magnetic field inhomogeneitics.

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A brain-computer interface (BCI) based on functional magnetic resonance imaging (fMRI) records noninvasively activity of the entire brain with a high spatial resolution. We present a fMRI-based BCI which performs data processing and feedback of the hemodynamic brain activity within 1.3 s. Using this technique, differential feedback and self-regulation is feasible as exemplified by the supplementary motor area (SMA) and parahippocampal place area (PPA). Technical and experimental aspects are discussed with respect to neurofeedback. The methodology now allows for studying behavioral effects and strategies of local self-regulation in healthy and diseased subjects.

These data provide evidence for two levels of speech motor control bound, most presumably, to motor preparation and execution processes. They also help to explain clinical observations such as an unimpaired or even accelerated speaking rate in Parkinson disease and slowed speech tempo, which does not fall below a rate of 3 Hz, in cerebellar disorders.

A classical tenet of clinical neurology proposes that cerebellar disorders may give rise to speech motor disorders (ataxic dysarthria), but spare perceptual and cognitive aspects of verbal communication. During the past two decades, however, a variety of higher-order deficits of speech production, e.g., more or less exclusive agrammatism, amnesic or transcortical motor aphasia, have been noted in patients with vascular cerebellar lesions, and transient mutism following resection of posterior fossa tumors in children may develop into similar constellations. Perfusion studies provided evidence for cerebello-cerebral diaschisis as a possible pathomechanism in these instances. Tight functional connectivity between the language-dominant frontal lobe and the contralateral cerebellar hemisphere represents a prerequisite of such long-distance effects. Recent functional imaging data point at a contribution of the right cerebellar hemisphere, concomitant with language-dominant dorsolateral and medial frontal areas, to the temporal organization of a prearticulatory verbal code ('inner speech'), in terms of the sequencing of syllable strings at a speaker's habitual speech rate. Besides motor control, this network also appears to be engaged in executive functions, e.g., subvocal rehearsal mechanisms of verbal working memory, and seems to be recruited during distinct speech perception tasks. Taken together, thus, a prearticulatory verbal code bound to reciprocal right cerebellar/left frontal interactions might represent a common platform for a variety of cerebellar engagements in cognitive functions. The distinct computational operation provided by cerebellar structures within this framework appears to be the concatenation of syllable strings into coarticulated sequences.

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Video games are an exciting part of new media. Although game play has been intensively studied, the underlying neurobiology is still poorly understood. Flow theory is a well-established model developed to describe subjective game experience. In 13 healthy male subjects, we acquired fMRI data during free play of a video game and analyzed brain activity based on the game content. In accordance with flow theory, we extracted the following factors from the game content: (i) balance between ability and challenge; (ii) concentration and focus; (iii) direct feedback of action results; (iv) clear goals; and (v) control over the situation/activity. We suggest that flow is characterized by specific neural activation patterns and that the latter can be assessed-at least partially-by content factors contributing to the emergence of flow. Each of the content factors was characterized by specific and distinguishable brain activation patterns, encompassing reward-related midbrain structures, as well as cognitive and sensorimotor networks. The activation of sensory and motor networks in the conjunction analyses underpinned the central role of simulation for flow experience. Flow factors can be validated with functional brain imaging which can improve the understanding of human emotions and motivational processes during media entertainment.

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