Entanglement contains one of the most interesting features of quantum mechanics, often named quantum non-locality [1,2]. This means entangled states are not separable regardless of the spatial separation of their components. Measurement results on one particle of a two-particle entangled state define the state of the other particle instantaneously with neither particle enjoying its own well-defined state before the measurement.So far experimental confirmation of entanglement has been restricted to qubits, i.e. two-state quantum systems including recent realization of three- [3,4] and four-qubit [5,6] entanglements. Yet, an ever increasing body of theoretical work calls for entanglement in quantum system of higher dimensions [7,8]. For photons one is restricted to qubits as long as the entanglement is realized using the photons polarization. Here we report the first realization of entanglement exploiting the orbital angular momentum of photons,

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The importance of the left occipitotemporal cortex for visual word processing is highlighted by numerous functional neuroimaging studies, but the precise function of the Visual Word Form Area (VWFA) in this brain region is still under debate. The present fMRI study varied orthographic familiarity independent from phonological-semantic familiarity by presenting orthographically familiar and orthographically unfamiliar forms (pseudohomophones) of the same words in a phonological lexical decision task. Consistent with orthographic word recognition in the VWFA, we found lower activation for familiar compared to unfamiliar forms, but no difference between pseudohomophones and pseudowords. This orthographic familiarity effect in the VWFA differed from the phonological familiarity effect in left frontal regions, where phonologically unfamiliar pseudowords led to higher activation than phonologically familiar pseudohomophones. We suggest that the VWFA not only computes letter string representations but also hosts word specific orthographic representations. These representations function as recognition units with the effect that letter strings, which readily match with stored representations lead to less activation than letter strings which do not.

Functional neuroimaging studies have consistently demonstrated less activation of the left occipitotemporal cortex in dyslexic readers. This region is considered critical for skilled reading and damage to it in adult readers leads to severe deficits in reading ability. In contrast to these findings, structural abnormalities in the occipitotemporal cortex were not consistently found to date. We used optimized Voxel Based Morphometry with T1 weighted MR images to investigate gray matter volume in 13 dyslexic and 15 nonimpaired reading adolescents (age 14-16). Less gray matter volume for dyslexic readers was found in the left and right fusiform gyrus, the bilateral anterior cerebellum and in the right supramarginal gyrus. Decreased gray matter volume in the left and right fusiform gyrus of dyslexic readers highlights the importance of this brain region for developmental dyslexia. The structural abnormalities in the right occipitotemporal cortex suggest that dyslexia may be such a persistent disorder because an occipitotemporal reading area, critical for skilled reading, cannot develop in any hemisphere. The extended areas of reduced gray matter volume in dyslexic readers in the cerebellum suggest that structural abnormalities in the cerebellum are also strongly associated with dyslexia and warrant further investigation.

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