The first steps in the process of reading a printed word belong to the domain of visual object perception. They culminate in a representation of letter strings as an ordered set of abstract letter ...identities, a representation known as the Visual Word Form (VWF). Brain lesions in patients with pure alexia and functional imaging data suggest that the VWF is subtended by a restricted patch of left-hemispheric fusiform cortex, which is reproducibly activated during reading. In order to determine whether the operation of this Visual Word Form Area (VWFA) depends exclusively on the visual features of stimuli, or is influenced by language-dependent parameters, brain activations induced by words, consonant strings and chequerboards were compared in normal subjects using functional MRI (fMRI). Stimuli were presented in the left or right visual hemifield. The VWFA was identified in both a blocked-design experiment and an event-related experiment as a left-hemispheric inferotemporal area showing a stronger activation to alphabetic strings than to chequerboards, and invariant for the spatial location of stimuli. In both experiments, stronger activations of the VWFA to words than to strings of consonants were observed. Considering that the VWFA is equally activated by real words and by readable pseudowords, this result demonstrates that the VWFA is initially plastic and becomes attuned to the orthographic regularities that constrain letter combination during the acquisition of literacy. Additionally, the use of split-field stimulation shed some light on the cerebral bases of the classical right visual field (RVF) advantage in reading. A left occipital extrastriate area was found to be activated by RVF letter strings more than by chequerboards, while no symmetrical region was observed in the right hemisphere. Moreover, activations in the precuneus and the left thalamus were observed when subjects were reading RVF versus left visual field (LVF) words, and are likely to reflect the attentional component of the RVF advantage.
Few cases of human papillomavirus (HPV) diseases have been reported in multiple sclerosis (MS) patients treated with fingolimod. We describe a case series of 16 MS patients (11 women, 5 men) ...developing HPV lesions after the onset of fingolimod, without previous HPV history. Fingolimod had to be discontinued in six patients. Six patients received vaccination for HPV, with good tolerance. Our report highlights that systematic HPV screening and discussion about HPV vaccination before fingolimod onset are crucial. In case of occurrence of HPV lesions during fingolimod treatment, a comprehensive workup of HPV disease is necessary, with discussion of HPV vaccination to prevent secondary lesions. Prevalence studies of HPV lesions are needed in MS patients with the different disease-modifying therapies.
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