Between 1 July 2010 and 31 July 2011 we recruited all patients who presented to the Department of Neurology with a speech and language disorder suspected to be secondary to a degenerative process. Only subjects over the age of 18, with an informant to provide independent evaluation of functioning, and who spoke English as their primary language, were included. All subjects underwent detailed speech and language examination, neurological evaluation, neuropsychological testing and neuroimaging analysis over a span of 48–72 h. Clinical diagnosis of PPAOS was rendered based solely on data from speech and language assessments without any reference to neurological, neuropsychological or neuroimaging results at a consensus meeting held 1–2 months after enrolment. All subjects had video and audio recordings of their entire comprehensive, formal speech and language assessment, as well as general conversation and performance on a measure of oral praxis.
Diagnosis was made according to operational definitions, after review of the video and audio recordings and review of speech and language test scores as described below. In order to be included in this study all subjects must have been diagnosed with PPAOS; any evidence suggesting aphasia could not be more than equivocal. Dysarthria could be present. Therefore, any subject with even mild (but unequivocal) evidence of aphasia was excluded. Subjects with concurrent illnesses that could account for the speech deficits, such as traumatic brain injury, stroke or developmental syndromes, and subjects meeting criteria for another neurodegenerative disease, such as Alzheimer’s type dementia (McKhann et al., 1984 (link)), dementia with Lewy bodies (McKeith et al., 2005 (link)), behavioural variant frontotemporal dementia (Neary et al., 1998 (link)), probable progressive supranuclear palsy (Litvan et al., 1996 (link)), corticobasal syndrome (Boeve et al., 2003 (link)), multiple system atrophy (Gilman et al., 2008 (link)), or motor neuron degeneration (Brooks et al., 2000 (link)) were excluded. Subjects were also excluded if MRI was contraindicated (metal in head, cardiac pace maker, etc.), if there was severe claustrophobia or conditions that might confound brain imaging studies (e.g. structural abnormalities, including subdural haematoma or intracranial neoplasm), or if they were medically unstable or were on medications that might affect brain structure or metabolism, (e.g. chemotherapy).
During this period, 40 subjects were screened of which 37 were recruited and three excluded (Supplementary Fig. 1 ). One subject was excluded due to a tiny chronic lacunar infarct in the left centrum semiovale and left subinsular white matter, one as a result of having a pacemaker, and one who was determined to meet clinical criteria for Alzheimer’s disease (McKhann et al., 1984 (link)).
The study was approved by the Mayo Clinic institutional review board and all subjects consented for enrolment into the study.
Diagnosis was made according to operational definitions, after review of the video and audio recordings and review of speech and language test scores as described below. In order to be included in this study all subjects must have been diagnosed with PPAOS; any evidence suggesting aphasia could not be more than equivocal. Dysarthria could be present. Therefore, any subject with even mild (but unequivocal) evidence of aphasia was excluded. Subjects with concurrent illnesses that could account for the speech deficits, such as traumatic brain injury, stroke or developmental syndromes, and subjects meeting criteria for another neurodegenerative disease, such as Alzheimer’s type dementia (McKhann et al., 1984 (link)), dementia with Lewy bodies (McKeith et al., 2005 (link)), behavioural variant frontotemporal dementia (Neary et al., 1998 (link)), probable progressive supranuclear palsy (Litvan et al., 1996 (link)), corticobasal syndrome (Boeve et al., 2003 (link)), multiple system atrophy (Gilman et al., 2008 (link)), or motor neuron degeneration (Brooks et al., 2000 (link)) were excluded. Subjects were also excluded if MRI was contraindicated (metal in head, cardiac pace maker, etc.), if there was severe claustrophobia or conditions that might confound brain imaging studies (e.g. structural abnormalities, including subdural haematoma or intracranial neoplasm), or if they were medically unstable or were on medications that might affect brain structure or metabolism, (e.g. chemotherapy).
During this period, 40 subjects were screened of which 37 were recruited and three excluded (
The study was approved by the Mayo Clinic institutional review board and all subjects consented for enrolment into the study.
