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The diagnostic criteria for progressive supranuclear palsy (PSP) incorporate two speech-language disturbances (SLDs), non-fluent/agrammatic primary progressive aphasia and progressive apraxia of speech, but overlook the inclusion of other SLDs, including dynamic aphasia (DA). Thus, there is a need to reappraise the broad spectrum of SLDs in PSP to include other presenting phenotypes. Here we report findings from the study of two elderly patients with PSP presenting with DA and irrepressible echolalia. Both patients had markedly impoverished verbal production, but their performance in other tasks (repetition and naming) and auditory comprehension were preserved or only mildly impaired. Experimental tests of DA revealed impaired word and sentence generation in response to verbal and non-verbal stimuli. Additional language and cognitive testing revealed different types of echolalia (mitigated, automatic, and echoing approval) as well as impaired inhibitory control and social cognition (mentalizing). Both patients had negative neuropsychiatric alterations (i.e., apathy, aspontaneity, and indifference/emotional flatness). Brain magnetic resonance imaging in both patients showed atrophy of the midbrain tegmentum and superior medial frontal cortex suggestive of PSP, yet further evaluation of the neural correlates using multimodal neuroimaging and neuropathological data was not performed. However, based on the already known neural basis of DA and echolalia in PSP and stroke, we suggest that, in the present cases, neurodegeneration in the midbrain tegmentum, superior medial frontal lobe, and caudate nucleus was responsible for DA and that decreased activity in these regions may play a permissive role for eliciting verbal echoing via disinhibition of the perisylvian speech-language network.

The acquisition and evolution of speech production, discourse and communication can be negatively impacted by brain malformations. We describe, for the first time, a case of developmental dynamic dysphasia (DDD) in a right-handed adolescent boy (subject D) with cortical malformations involving language-eloquent regions (inferior frontal gyrus) in both the left and the right hemispheres. Language evaluation revealed a markedly reduced verbal output affecting phonemic and semantic fluency, phrase and sentence generation and verbal communication in everyday life. Auditory comprehension, repetition, naming, reading and spelling were relatively preserved, but executive function was impaired. Multimodal neuroimaging showed a malformed cerebral cortex with atypical configuration and placement of white matter tracts bilaterally and abnormal callosal fibers. Dichotic listening showed right hemisphere dominance for language, and functional magnetic resonance imaging (fMRI) additionally revealed dissociated hemispheric language representation with right frontal activation for phonology and bilateral dominance for semantic processing. Moreover, subject D also had congenital mirror movements (CMM), defined as involuntary movements of one side of the body that mirror intentional movements of the other side. Transcranial magnetic stimulation and fMRI during voluntary unimanual (left and right) hand movements showed bilateral motor cortex recruitment and tractography revealed a lack of decussation of bilateral corticospinal tracts. Genetic testing aimed to detect mutations that disrupt the development of commissural tracts correlating with CMM (e.g., Germline DCC mutations) was negative. Overall, our findings suggest that DDD in subject D resulted from the underdevelopment of the left inferior frontal gyrus with limited capacity for plastic reorganization by its homologous counterpart in the right hemisphere. Corpus callosum anomalies probably contributed to hinder interhemispheric connectivity necessary to compensate language and communication deficits after left frontal involvement.

Verbal adynamia (impaired language generation, as during conversation) has not been assessed systematically in parkinsonian disorders. We addressed this in patients with Parkinson’s dementia, progressive supranuclear palsy and corticobasal degeneration. All disease groups showed impaired verbal fluency and sentence generation versus healthy age-matched controls, after adjusting for general linguistic and executive factors. Dopaminergic stimulation in the Parkinson’s group selectively improved verbal generation versus other cognitive functions. Voxel-based morphometry identified left inferior frontal and posterior superior temporal cortical correlates of verbal generation performance. Verbal adynamia warrants further evaluation as an index of language network dysfunction and dopaminergic state in parkinsonian disorders.

Objective: To study whether pressure of speech in jargon aphasia arises out of disturbances to core language or executive processes, or at the intersection of conceptual preparation. Background: Conceptual preparation mechanisms for speech have not been well studied. Several mechanisms have been proposed for jargon aphasia, a fluent, well-articulated, logorrheic propositional speech that is almost incomprehensible. Methods: We studied the vast quantity of jargon speech produced by patient J.A., who had suffered an infarct after the clipping of a middle cerebral artery aneurysm. We gave J.A. baseline cognitive tests and experimental word-and sentencegeneration tasks that we had designed for patients with dynamic aphasia, a severely reduced but otherwise fairly normal propositional speech thought to result from deficits in conceptual preparation. Results: J.A. had cognitive dysfunction, including executive difficulties, and a language profile characterized by poor repetition and naming in the context of relatively intact single-word comprehension. J.A.'s spontaneous speech was fluent but jargon. He had no difficulty generating sentences; in contrast to dynamic aphasia, his sentences were largely meaningless and not significantly affected by stimulus constraint level. Conclusions: This patient with jargon aphasia highlights that voluminous speech output can arise from disturbances of both language and executive functions. Our previous studies have identified three conceptual preparation mechanisms for speech: generation of novel thoughts, their sequencing, and selection. This study raises the possibility that a "brake" to stop message generation may be a fourth conceptual preparation mechanism behind the pressure of speech characteristic of jargon aphasia.

Introduction The symptomatology of transcortical motor aphasia (TMA) or dynamic aphasia (Luria & Tsvetkova, 1970) allows the clinician to investigate “the particularly interesting stage in transition from initial thought to final verbal expression” and “to study in pure form the lack of speech initiative” (Rubens, 1976,p. 302). The symptoms described in the literature include: difficulty initiating speech, limited spontaneous speech, intact repetition, good auditory comprehension. In contrast, agrammatic sentence production is associated with Broca’s aphasia. Language data from a participant presenting with TMA and also agrammatic symptoms who showed a good recovery are analyzed. The aim of this presentation is to tease apart the observed language features to arrive at a better understanding of the nature of specific symptoms and their impact on language processing. Methods Participant GS: a 17-year-old carpenter’s apprentice, suffered a massive stroke. A complete occlusion of the left anterior-cerebral-artery was diagnosed. Procedure From 4 weeks to 10 months post onset GS was administered standardized language tests and tasks covering all linguistic levels. A matched control person (MH) was also tested. Results Selected results and examples are given in Table 1. GS’s initiation of spontaneously produced speech is captured by his slow rate of production and verbal output for texts in comparison to control MH. As shown in Table 1, specific syntactic features showed impairment. At six months his aphasia had evolved into a mild impairment. Discussion The utterances produced by a classical TMA patient are usually grammatical. In part, this applies to G.S. However, he also reveals the following difficulties: simplification of syntactic structure, substitutions and omissions of articles, frequent omission of prepositions, verb agreement and selection errors, and reversal of subject and object noun phrases various sentence and discourse level tasks. GS’s difficulties initiating spontaneous speech in comparison to the relative sparing of speech evoked through external stimulation – especially repetition of spoken language, visual confrontation naming and good auditory comprehension skills can be distinguished from the agrammatic symptomatology by classifying GS as presenting with the third type of transcortical motor aphasia put forward by Freedman, Alexander, & Naeser (1984): “TMA during recovery from Broca’s aphasia”. Kleist (1934) provides support for this third type of TMA; he stressed that patients with ‘adynamic language’ revealed difficulty producing sentences to the point of agrammatism. Based on analyses of GS’s initial symptoms and the evolution of his language skills, those features associated with TMA can be distinguished from the Broca’s agrammatic symptoms. The agrammatic deficits are considered in part to stem from an Impairment of automatic processing. Due to the long latencies in initiating his utterances those categories particularly affected in GS, namely the omission of articles and prepositions, are exactly those features put forward by Whitaker (1976) to be automatically processed. On the other hand, the reversal errors are associated with an impairment of the linear scheme of the phrase observed in dynamic aphasia. In summary, despite an initial massive lesion, GS showed a remarkable recovery as shown by his language profile at six months post onset.

BACKGROUND: Idiopathic basal ganglia calcification (IBGC), also known as Fahr's disease, is a rare disorder characterized by widespread cerebral calcifications, an autosomal dominant pattern of inheritance and clinical and genetic heterogeneity. The recently identified IBGC gene, SLC20A2, encodes for type III sodium-dependent phosphate transporter 2 and its loss-of-function mutations may lead to the regional accumulation of inorganic phosphate in the brain, causing calcium phosphate deposition. OBJECTIVE: To describe the clinical, neuroimaging and genetic findings in an Italian family with IBGC. METHODS: The family members underwent clinical and radiological examination in order to diagnose IBGC according to standard criteria and screening for SLC20A2 gene mutations. The affected subjects also underwent neuropsychological longitudinal assessments and functional neuroimaging investigations. RESULTS: The 2 affected family members harbored a novel missense mutation, G1618A, in the SLC20A2 gene, leading to gly540-to-arg (G540R) substitution in a highly conserved residue. This is the first SLC20A2 gene mutation associated with familial IBGC reported in the Italian population and is damaging according to all prediction programs. In the index case we observed a fair correlation between cortical areas with no calcifications but with significant hypometabolism at [18F]FDG-PET (inferior frontal premotor cortex) and the neuropsychological picture dominated by dynamic aphasia and buccofacial apraxia. CONCLUSION: These findings expand the catalog of SLC20A2 mutations identified to date and add dynamic aphasia to the spectrum of neuropsychological deficits reported in IBGC, supporting the use of functional neuroimaging studies for better investigation of genotype-phenotype correlations.