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During the past 2 decades the collaboration across disciplines and the methodologic and conceptual advances of contemporary neuroscience have brought about a substantial modification of the traditional view of the cerebellum as a mere coordinator of autonomic and somatic motor functions. Growing insights in the neuroanatomy of the cerebellum and its interconnections, evidence from functional neuroimaging and neurophysiological research, and advancements in clinical and experimental neuropsychology have established the view that the cerebellum participates in a much wider range of functions than conventionally accepted. This increase of insight has brought to the fore that the cerebellum modulates cognitive functioning of at least those parts of the brain to which it is reciprocally connected. This article reviews the recently acknowledged role of the cerebellum in cognition and addresses in more detail experimental and clinical data disclosing the modulatory role of the cerebellum in various non-motor language processes such as lexical retrieval, syntax, and language dynamics. In agreement with the findings indicating a topographical organization of the cerebellar structures involved in language pathology we advance the concept of a “lateralized linguistic cerebellum.” In our view crossed cerebral diaschisis processes, reflecting a functional depression of supratentorial language areas due to reduced input via cerebellocortical pathways, might represent the relevant pathomechanism for linguistic deficits associated with cerebellar pathology.

In contrast to the estimated low incidence of crossed aphasia in dextral adults (among 1%), crossed aphasia in children has been considered a common finding for almost a century. However, reviewing the literature on crossed aphasia in dextrals (CAD) and its related topics from 1975 onward, we encountered only 5 children in a corpus of 180 cases (2.7%). Critical analysis rendered three of the reported cases ambiguous and hence not suitable to draw potentially relevant conclusions. In this review, the neurobehavioral manifestations of the two representative childhood CAD cases are analyzed and compared with adult CAD and acquired childhood aphasia (ACA). In the light of our findings, which support the position of innate cerebral specialization for language, the long-standing controversy as to whether lateralized hemispheric specialization for language is innate or develops progressively during maturation is briefly discussed.

Following a dramatic change of its reported incidence, it was only recently recognized that acquired crossed aphasia in dextral children represents a highly exceptional phenomenon. We describe in a three epoch time-frame model the aphasic and neurocognitive manifestations of an additional case and focus briefly on its anatomoclinical configurations. In our patient, a right parietal cortico-subcortical hemorrhagic lesion caused an initially severe aphasia. After remission of the global aphasic symptoms in the acute phase, an adynamic output disorder with relatively severe auditory–verbal comprehension disturbances developed. In addition to the adynamia of self-generated speech, formal language investigations performed 3 weeks postonset, revealed agrammatism, hypertonic dysarthria, and dysprosodia. A substantial improvement of the aphasic disorder was objectified 83 days postonset. Neuropsychological investigations disclosed both dominant and nondominant hemisphere dysfunctions. Reassessment of neurocognitive functions after a 10-year period evidenced discrete residual anomia, confined to visual confrontational naming and a discrete visuo-perceptual syndrome. Given the posterior localization of the lesion, the syndrome shift from global to predominantly adynamic aphasia represents a finding beyond the plausible anatomoclinical expectations holding in general for the uncrossed, classic types of childhood and adult aphasia. As the first representative of crossed aphasia in dextral children with an anomalous lesion–aphasia profile, our case provides evidence to enrich the discussion on lateralization and intrahemispherical organization of language functions in both childhood and adult aphasia.

A normative study of the 60-item version of the Boston Naming Test (BNT) was performed in a group of 200 native Dutch-speaking Flemish elderly. Analysis of test results revealed that BNT performance in Dutch is significantly affected by age, years of education, and gender. Error analysis disclosed verbal semantic paraphasias to occur as the most frequent error type (1/3 errors). “Don't know responses,” verbal semantic paraphasias, and adequate circumlocutions were found on at least 30 different BNT items and constituted the most diffusely distributed error types. Following a careful review of other normative BNT studies, group characteristics rather than cultural differences were found to account for the difference in the overall mean scores. Our study surprisingly revealed that, as far as American–English, Australian–English and Dutch-speaking elderly are concerned, linguistics do not have an impact on the overall mean BNT score. A linguistic impact, however, clearly holds on the qualitative levels of performance, reflected by fundamental differences in the error distribution in different languages. Language-related BNT characteristics therefore stress the need for specific adaptations of norms.