Intentional mechanisms play an important role in complex self-initiated actions, such as language and gesturing. Deficits demonstrated in nonfluent aphasia may be a result of a disconnection between or damage to the initiation (intention) and production mechanisms in the left hemisphere. In chronic nonfluent aphasias, damaged language production mechanisms in the left hemisphere may switch to h...

The pathophysiology of primary progressive aphasias remains poorly understood. Here, we addressed this issue using activation fMRI in a cohort of 27 patients with primary progressive aphasia (nonfluent, semantic, and logopenic variants) versus 15 healthy controls. Participants listened passively to sequences of spoken syllables in which we manipulated 3-key auditory speech signal characteristic...

BACKGROUND Primary progressive aphasia (PPA) is a degenerative disease that presents as progressive decline of language ability with preservation of other cognitive functions in the early stages. Three subtypes of PPA are known: progressive nonfluent aphasia, semantic dementia, and logopenic aphasia (LPA). PATIENTS AND METHODS We report the case of a 77-year-old patient with PPA whose clinica...

Background Frontotemporal dementia (FTD) is one of the most frequent dementia types in patients under 65 years of age. Currently, no therapy can effectively improve the cognitive deficits associated with FTD. Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive method of inducing brain plasticity with therapeutic potential in neurodegenerative diseases. The purpose of this study...

Abnormal responsiveness to salient sensory signals is often a prominent feature of dementia diseases, particularly the frontotemporal lobar degenerations, but has been little studied. Here we assessed processing of one important class of salient signals, looming sounds, in canonical dementia syndromes. We manipulated tones using intensity cues to create percepts of salient approaching ("looming...

The title compound, [Ni(C(14)H(16)N(5)O(3))(2)](n) or [Ni(ppa)(2)](n), where ppa is 8-ethyl-5-oxo-2-(piperazin-1-yl)-5,8-dihydro-pyrido[2,3-d]pyrimidine-6-carboxyl-ate, was synthesized under hydro-thermal conditions. The Ni(II) atom (site symmetry ) exhibits a distorted trans-NiN(2)O(4) octa-hedral geometry defined by two monodentate N-bonded and two bidentate O,O'-bonded ppa monoanions. The ex...

OBJECTIVE A brief speech expression protocol that can be administered and scored without special training would aid in the differential diagnosis of the 3 principal forms of primary progressive aphasia (PPA): nonfluent/agrammatic PPA, logopenic variant PPA, and semantic variant PPA. METHODS We used a picture-description task to elicit a short speech sample, and we evaluated impairments in spe...