Bach speaks: A cortical "language-network" serves the processing of music

The aim of the present study was the investigation of neural correlates of music processing with fMRI. Chord sequences were presented to the participants, infrequently containing unexpected musical events. These events activated the areas of Broca and Wernicke, the superior temporal sulcus, Heschl's gyrus, both planum polare and planum temporale, as well as the anterior superior insular cortices. Some of these brain structures have previously been shown to be involved in music processing, but the cortical network comprising all these structures has up to now been thought to be domain-specific for language processing. To what extent this network might also be activated by the processing of non-linguistic information has remained unknown. The present fMRI-data reveal that the human brain employs this neuronal network also for the processing of musical information, suggesting that the cortical network known to support language processing is less domain-specific than previously believed

Regional differences of fMR signal changes induced by hyperventilation: Comparison between SE-EPI and GE-EPI at 3-T

PURPOSE: To evaluate whether reproducible signal change of brain tissues by hyperventilation (HV) can be seen on spin-echo (SE)-echo planar imaging (EPI) at 3-T and to examine the sensitivity of SE-EPI for measuring vascular reactivity in regions of the brain, such as the hippocampal formation, that are difficult to visualize with gradient-echo (GE)-EPI due to susceptibility artifacts. MATERIALS AND METHODS: Six healthy human subjects performed a voluntary HV task. The task design was as follows: two minutes normal breathing (rest) followed by two minutes HV, giving a basic four-minute block that was repeated three times for a total scan time of 12 minutes for one run. Each subject performed the run both for SE-EPI and GE-EPI. Statistical analysis was performed to detect the area with significant cerebrovascular reactivity. The percentage signal change was also obtained for each cerebral region. RESULTS: Both GE-EPI and SE-EPI showed globally significant signal decreases in the cerebral cortex. In GE-EPI, the frontal cortex showed a larger signal decrease than the other gray matter tissues (P < 0.05). In SE-EPI, the differences among gray matter tissues except for the hippocampal formation were not significant. The hippocampal formation showed the largest signal change (P < 0.05) in SE-EPI, but no significant signal change was observed in GE-EPI due to the presence of susceptibility artifacts. CONCLUSION: HV using SE-EPI at 3-T provides robust and reproducible signal decreases and may make the evaluation of the vascular reactivity in hippocampal formation feasible

Nonlinear optical properties of push–pull polyenes for electro-optics

Improved nonlinear organic chromophores of varying conjugation length with either thiobarbituric acid or 3-dicyanomethylene-2,3-dihydrobenzothiophene-1,1-dioxide (FORON® Blue) acceptors have been synthesized and investigated for their nonlinear optical properties. Very large quadratic hyperpolarizabilities β(−2ω; ω, ω) have been found, up to 25,700×10^(−48) esu at λ=1.91 μm. In a guest–host polymer very high electro-optic (EO) coefficients, of up to 55 pm/V, have been determined at λ=1.31 μm with 20-wt % chromophore loading. We find good agreement between molecular parameters evaluated by electric-field-induced second-harmonic generation (EFISH) and the measurements of guest–host solid–solid solutions. The latter method is well suited to the determination of the product of dipole moment μ and hyperpolarizability β quickly and reliably at the wavelength of interest for EO applications without the complications associated with EFISH measurements

Wavelet statistics of functional MRI data and the general linear model

PURPOSE: To improve the signal-to-noise ratio (SNR) of functional magnetic resonance imaging (fMRI) data, an approach is developed that combines wavelet-based methods with the general linear model. MATERIALS AND METHODS: Ruttimann et al. (1) developed a wavelet-based statistical procedure to test wavelet-space partitions for significant wavelet coefficients. Their method is applicable for the detection of differences between images acquired under two experimental conditions using long blocks of stimulation. However, many neuropsychological questions require more complicated event-related paradigms and more experimental conditions. Therefore, in order to apply wavelet-based methods to a wide range of experiments, we present a new approach that is based on the general linear model and wavelet thresholding. RESULTS: In contrast to a monoresolution filter, the application of the wavelet method increased the SNR and showed a set of clearly dissociable activations. Furthermore, no relevant decrease of the local maxima was observed. CONCLUSION: Wavelet-based methods can increase the SNR without diminishing the signal amplitude, while preserving the spatial resolution of the image. The anatomical localization is strongly improved

Within-subject variability of BOLD response dynamics

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Reengineered helmet coil for human brain studies at 3 tesla

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Near-infrared spectroscopy can detect brain activity during a color-word matching Stroop task in an event-related design

Brai nactivit ycanbemonitore dnon-invasivel ybynear-infrare dspectroscop y(NIRS) ,whic hhas severa ladvantage sincompariso nwit hothe rimagin gmethods ,suc hasflexibility ,portability ,low cost an dbiochemica lspecificity .Moreover ,patient san dchildre ncanberepetitivel yexamined .Therefore ,the objectiv eofthestud ywa stotes tthefeasibilit yofNIR Sfortheevent-relate dapproac hinfunctiona lbrain activatio nstudie swit hcognitiv eparadigms .Thus ,change sintheconcentratio nofoxy- ,deoxy- ,an dtotal hemoglobi nwer emeasure d byNIR Sin14health ysubject swhil eperformin ga color–wor d matching Stroo p tas k in an event-relate d design .Th ehemodynami crespons e(increas ein theconcentratio n of oxy-/tota lhemoglobi n an d decreas ein theconcentratio n ofdeoxy-hemoglobin )wa sstronge rduring incongruen tcompare dtocongruen tan dneutra ltrial softheStroo ptas kinthelatera lprefronta lcortex bilaterally .Thi sstronge rhemodynami crespons ewa sinterprete dasa stronge rbrai nactivatio nduring incongruen ttrial softheStroo ptask ,du etointerference .A ne w metho dforNIR Sdat aevaluatio nthat enable stheanalysi softhehemodynami crespons etoeac hsingl etria lisintroduced .Eac hhemodynamic respons ewa scharacterize dbytheparameter sgain ,lagan ddispersio nofa Gaussia nfunctio nfitte dby nonlinea rregression .Specifi cdifference sbetwee ntheincongruen tan dneutra lconditio nwer efoun dfor gai nan dlag .Further ,thes eparameter swer ecorrelate dwit hthebehaviora lperformance .Inconclusion, brai nactivit yma ybestudie d byNIR Susin gcognitiv estimul iinanevent-relate d design

Challenges and insights in the exploration of the low abundance human ocular surface microbiome.

PURPOSE The low microbial abundance on the ocular surface results in challenges in the characterization of its microbiome. The purpose of this study was to reveal factors introducing bias in the pipeline from sample collection to data analysis of low-abundant microbiomes. METHODS Lower conjunctiva and lower lid swabs were collected from six participants using either standard cotton or flocked nylon swabs. Microbial DNA was isolated with two different kits (with or without prior host DNA depletion and mechanical lysis), followed by whole-metagenome shotgun sequencing with a high sequencing depth set at 60 million reads per sample. The relative microbial compositions were generated using the two different tools MetaPhlan3 and Kraken2. RESULTS The total amount of extracted DNA was increased by using nylon flocked swabs on the lower conjunctiva. In total, 269 microbial species were detected. The most abundant bacterial phyla were Actinobacteria, Firmicutes and Proteobacteria. Depending on the DNA extraction kit and tool used for profiling, the microbial composition and the relative abundance of viruses varied. CONCLUSION The microbial composition on the ocular surface is not dependent on the swab type, but on the DNA extraction method and profiling tool. These factors have to be considered in further studies about the ocular surface microbiome and other sparsely colonized microbiomes in order to improve data reproducibility. Understanding challenges and biases in the characterization of the ocular surface microbiome may set the basis for microbiome-altering interventions for treatment of ocular surface associated diseases

The emergence of the unmarked: A new perspective on the language-specific function of Broca's Area

A number of neuroimaging studies have implicated an involvement of Broca's area, particularly of the pars opercularis of the left inferior frontal gyrus (IFG), in the processing of complex (permuted) sentences. However, functional interpretations of this region's role range from very general (e.g., in terms of working memory) to highly specific (e.g., as supporting particular types of syntactic operations). A dissociation of these competing accounts is often impossible because in most cases, the language internal complexity of permuted sentence structures is accompanied invariably by increasing costs of a more general cognitive nature (e.g., working memory, task difficulty, and acceptability). We used functional magnetic resonance imaging to explore the precise nature of the pars opercularis activation in the processing of permuted sentences by examining the permutation of pronouns in German. Although clearly involving a permutation operation, sentences with an initial object pronoun behave like simple, subject-initial sentences (e.g., in terms of acceptability) because of a rule stating that pronouns should generally precede non-pro-nominal arguments. The results of the experiment show that in contrast to non-pro-nominal permutations, sentences with a permuted pronoun do not engender enhanced pars opercularis activation. Our findings therefore speak against both language-related working memory and transformation-based accounts of this region's role in sentence comprehension. Rather, we argue that the pars opercularis of the left IFG supports the language-specific linearization of hierarchical linguistic dependencies

The neural implementation of multi-attribute decision making: A parametric fMRI study with human subjects

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