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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.

The study presented here investigated the effects of emotional valence on the memory for words by assessing both memory performance and pupillary responses during a recognition memory task. Participants had to make speeded judgments on whether a word presented in the test phase of the experiment had already been presented ("old") or not ("new"). An emotion-induced recognition bias was observed: Words with emotional content not only produced a higher amount of hits, but also elicited more false alarms than neutral words. Further, we found a distinct pupil old/new effect characterized as an elevated pupillary response to hits as opposed to correct rejections. Interestingly, this pupil old/new effect was clearly diminished for emotional words. We therefore argue that the pupil old/new effect is not only able to mirror memory retrieval processes, but also reflects modulation by an emotion-induced recognition bias.

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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.