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This study assesses the interest of a simple fMRI rhyme detection paradigm to determine hemispheric predominance for language in epileptic patients. Nineteen patients were examined. The findings derived from the fMRI examinations were compared with those obtained on the same patients using the Wada test, stereotactic intracerebral EEG stimulations and recordings, and/or video‐EEG recordings. For the seventeen patients for whom language dominance could be assessed by means of at least one of the latter procedures, the fMRI examination provided concordant results in sixteen. In two patients, the hemispheric predominance for language could only be determined by fMRI. Nine patients underwent surgery subsequent to the fMRI examination. None of them exhibited any aphasic problems following surgery. The rhyme detection task used in the fMRI examination generates robust responses in the language areas, permits easy monitoring of the patient's task performance and can be easily undertaken by the epileptic patients. Thus, this study demonstrates that the fMRI rhyme detection paradigm is particularly well‐suited for determining hemispheric language predominance in epileptic candidates for surgery.

Patients with Alzheimer's disease (AD) produce a high rate of semantic errors when naming to confrontation. This is considered to be one of the many consequences of their semantic memory deficit. However, it has been shown, in aphasic patients with focal lesions, that semantic errors could arise from impairment to any one of the levels in the naming process. To check this hypothesis in AD, we assessed in 15 patients the capacity to name and access semantic knowledge (by multiple-choice probe questions) about 14 objects presented successively in the visual, tactile, auditory, and verbal modalities. In the visual naming task, 33 errors were recorded: 26 (78.8%) were semantic and 7 (21.2%) were unrelated errors. Of the 26 semantic errors, 8 were related to a deficit of the semantic knowledge related to the item and 17 to a deficit in the retrieval of the phonological form of the word. One was associated with a deficit of access to semantic knowledge in the visual modality. The 7 unrelated errors were associated with a loss of semantic knowledge for 4 and deficit of access to the phonological form for 3. In conclusion, this study shows that semantic errors do not systematically reflect a deficit of semantic knowledge in Alzheimer's disease. It also seems that unrelated errors are more frequently related to semantic deficits than semantic errors in this population.

Following cerebral anoxia, EC, a 55-year-old patient, exhibited a severe and clear-cut pattern of semantic impairments without general intellectual deficit or perceptual difficulty. EC demonstrated a complex neuropsychological picture including a massive visual agnosia and a complete lack of imagery, both of which involved all categories of objects (living and non living) and a category-specific word comprehension deficit limited to animal names. Findings are discussed in the light of the theoretical frameworks currently available in the area of neuropsychology. It is argued that neither the single nor the multiple view of semantics fully succeed in providing a satisfactory account of the data and a tentative interpretation of the whole pattern of impairment is proposed in the general framework of non abstractive conceptions of meaning.