Neologistic jargon aphasia and agraphia in primary progressive aphasia

The terms 'jargon aphasia' and 'jargon agraphia' describe the production of incomprehensible language containing frequent phonological, semantic or neologistic errors in speech and writing, respectively. Here we describe two patients with primary progressive aphasia (PPA) who produced neologistic jargon either in speech or writing. We suggest that involvement of the posterior superior temporal-inferior parietal region may lead to a disconnection between stored lexical representations and language output pathways leading to aberrant activation of phonemes in neologistic jargon. Parietal lobe involvement is relatively unusual in PPA, perhaps accounting for the comparative rarity of jargon early in the course of these diseases.

Generalized and symptom-specific insight in behavioral variant frontotemporal dementia and primary progressive aphasia

Behavioral variant frontotemporal dementia (FTD) and primary progressive aphasia (PPA) are related dementias with different presenting symptoms but with increasing symptom overlap as they progress. Loss of insight is associated with early behavioral variant FTD, but not PPA. This study used the Frontal Behavioral Inventory to compare patient and caregiver concepts of symptom presence and severity. Patients with behavioral variant FTD were found to have worse insight overall than PPA patients. However, the PPA group showed reduced insight into behavioral symptoms, and the behavioral variant FTD groups had intact insight into some language symptoms. Theoretical and clinical implications are discussed.

Neuropsychiatric symptoms in behavioral variant frontotemporal dementia and primary progressive aphasia

Neuropsychiatric symptoms are well defined in behavioral variant frontotemporal dementia but are not as well studied in primary progressive aphasia. This study compared caregiver reported neuropsychiatric symptoms in these 2 forms of dementia at short and long disease duration. Patients with behavioral variant frontotemporal dementia had more symptoms than patients with primary progressive aphasia. However, when divided by duration of disease, patients with primary progressive aphasia with long duration had a similar number of symptoms to patients with behavioral variant frontotemporal dementia at either duration. Furthermore, this group of patients with primary progressive aphasia had more symptoms typical of behavioral variant frontotemporal dementia and less mood-related symptoms which were more common in patients with primary progressive aphasia with shorter duration. This study illustrates the emergence of neuropsychiatric symptoms as primary progressive aphasia progresses and highlights the increasing overlap with behavioral variant frontotemporal dementia because the disease affects areas outside of the language network.

Correlative studies of structural and functional imaging in primary progressive aphasia

RATIONALE

To compare and contrast structural and functional imaging in primary progressive aphasia (PPA).

METHODS

A cohort of 8 patients diagnosed with PPA presenting with nonfluency were prospectively evaluated. All patients had structural imaging in the form of MRI and in 1 patient CAT scanning on account of a cardiac pacemaker. All patients had single-photon emission computed tomography (SPECT) and positron emission tomography (PET) imaging.

RESULTS

SPECT and PET imaging had 100% correlation. Anatomical imaging was abnormal in only 6 of the 8 patients. Wernicke's area showed greater peak Z score reduction and extent of area affected than Broca's area (McNemar paired test: P = .008 for Z score reduction; P = .0003 for extent). PET scanning revealed significant involvement of the anterior cingulum.

CONCLUSION

Functional imaging in PPA: (a) identified more patients correctly than anatomic imaging highlighting the importance of SPECT and PET in the diagnosis; and (b) demonstrated the heterogeneous involvement of disordered linguistic networks in PPA suggesting its syndromic nature.

Progressive aphasia secondary to Alzheimer disease vs FTLD pathology

BACKGROUND

The pathology causing progressive aphasia is typically a variant of frontotemporal lobar degeneration, especially with ubiquitin-positive inclusions (FTLD-U). Less commonly the underlying pathology is Alzheimer disease (AD).

OBJECTIVE

To compare clinicopathologic and MRI features of subjects with progressive aphasia and AD pathology to subjects with aphasia and FTLD-U pathology and subjects with typical AD.

METHODS

We identified 5 subjects with aphasia and AD pathology and 5 with aphasia and FTLD-U pathology with an MRI from a total of 216 aphasia subjects. Ten subjects with typical AD clinical features and AD pathology were also identified. All subjects with AD pathology underwent pathologic reanalysis with TDP-43 immunohistochemistry. Voxel-based morphometry (VBM) was used to assess patterns of gray matter atrophy in the aphasia cases with AD pathology, aphasia cases with FTLD-U, and typical AD cases with AD pathology, compared with a normal control group.

RESULTS

All aphasic subjects had fluent speech output. However, those with AD pathology had better processing speed than those with FTLD-U pathology. Immunohistochemistry with TDP-43 antibodies was negative. VBM revealed gray matter atrophy predominantly in the temporoparietal cortices, with notable sparing of the hippocampus in the aphasia with AD subjects. In comparison, the aphasic subjects with FTLD-U showed sparing of the parietal lobe. Typical AD subjects showed temporoparietal and hippocampal atrophy.

CONCLUSIONS

A temporoparietal pattern of atrophy on MRI in patients with progressive fluent aphasia and relatively preserved processing speed is suggestive of underlying Alzheimer disease pathology rather than frontotemporal lobar degeneration with ubiquitin-only immunoreactive changes.

A review on primary progressive aphasia

Primary progressive aphasia (PPA) is a neurodegenerative disease of insidious onset presenting with progressive isolated loss of language function, without significant impairment in other cognitive domains. Current diagnostic criteria require the language dysfunction to remain isolated for at least two years, and to remain the salient feature as the disease progresses, usually to involve other domains such as behavior, executive functions, and judgment. Although PPA in its early stages can usually be differentiated from probable Alzheimer's disease (PRAD) and the behavioral variant of frontotemporal lobar degeneration by the absence of significant changes in memory and behavior, and the preservation of activities daily living, progression of the disease often leads to deficits more consistent with the latter. Underlying etiologies remain heterogeneous: the neuropathological characteristics associated with frontotemporal lobar degeneration, cortocobasal degeneration, and motor neuron disease are usually found. There is a strong genetic susceptibility with affliction of first-degree relatives with similar disease in up to 40 to 50% in some series. Pathogenic mutations in genes coding for the proteins tau and progranulin have been isolated. These are leading to a better understanding of the neuropathological mechanisms and hopefully targeted disease-modifying therapy. Current therapy is limited to improving mood symptoms and targeting behavior changes as they develop. Referral to specialized centers where speech therapy, counseling, and education for both patient and caregiver are available may be helpful.

Underdiagnosis of frontotemporal lobar degeneration in Brazil

Frontotemporal lobar degeneration (FTLD) is a progressive neurodegenerative disorder that involves the frontal and anterior temporal lobes. It is characterized by prominent behavioral and language disorders. There are three variants of FTLD: frontotemporal dementia (FTD), semantic dementia (SD) and progressive non-fluent aphasia (PNFA). FTLD may be mistaken for AD (Alzheimer’s disease) or psychiatric disorders especially in the early stages.

The mini-mental state examination in behavioral variant frontotemporal dementia and primary progressive aphasia

There is little information regarding the usefulness of the Mini-Mental State Examination (MMSE) for tracking progression of non-Alzheimer's disease dementias. This study examined the utility of the MMSE in capturing disease severity in the behavioral variant frontotemporal dementia (bvFTD) and primary progressive aphasia (PPA), 2 nonamnestic clinical dementia syndromes. Retrospective data from 41 bvFTD and 30 PPA patients were analyzed. bvFTD patients' change in MMSE scores over time was significantly correlated with change over time on a measure of activities of daily living. In contrast, PPA patients' MMSE scores showed greater decline over time than scores on the activities of daily living scale. Results suggest that the MMSE score, heavily dependent on language skill, overestimates dementia severity in PPA patients. However, the score may be a more accurate measure of functional impairment in bvFTD due to the influence of their executive function and attentional deficits on MMSE performance.

Semantic dementia Brazilian study of nineteen cases

The term semantic dementia was devised by Snowden et al. in 1989 and nowadays, the semantic dementia syndrome is recognized as one of the clinical forms of frontotemporal lobar degeneration (FTLD) and is characterized by a language semantic disturbance associated to non-verbal semantic memory impairment.

Altered effective connectivity within the language network in primary progressive aphasia

Primary progressive aphasia (PPA) is a neurodegenerative dementia syndrome principally characterized by the gradual dissolution of language functions, especially in the early stages of disorder. In a previous functional neuroimaging study, PPA patients were found to activate core language areas similarly to control subjects when performing semantic and phonological processing tasks (Sonty et al., 2003). In the present study, functional magnetic resonance imaging (fMRI) and dynamic causal modeling (DCM) were used to study multiregional effective connectivity in early-stage PPA (n = 8) and control (n = 8) subjects performing semantic word matching and visual letter matching tasks. fMRI analysis showed semantic task-specific activations in the left inferior frontal (Broca's area) and posterior superior temporal (Wernicke's area) regions, in addition to other language regions, in both groups. Using a model language network consisting of six left hemisphere regions, the DCM analysis demonstrated reduced language-specific effective connectivity between Wernicke's and Broca's areas in the PPA patient group. Furthermore, this decrement in connectivity was predictive of semantic task accuracy. These results demonstrate for the first time that dysfunctional network interactions (effective connectivity), rather than hypoactivity within individual brain regions, may contribute to the emergence of language deficits seen in PPA.

Frontotemporal dementia classification and neuropsychiatry

BACKGROUND

Frontotemporal dementia (FTD) is a syndrome encompassing the clinical expression of frontal or temporal lobe degeneration. The many clinical phenotypes of FTD include primary progressive aphasias and a more common frontotemporal degeneration with less marked language alteration but significant behavioral changes.

SUMMARY

This paper describes the clinical progression of neuropsychiatric symptoms among 62 predominantly behavioral presentations and 30 language presentations of FTD. Disinhibition and depression became common for both subject groups over the course of illness. Significantly more cases presenting with behavioral changes had apathy and disinhibition.

CONCLUSIONS

Language presentations of FTD had longer latency to onset of distinct neuropsychiatric changes but eventually converge with the phenotype initially affected with behavioral change. Clinicians should anticipate such neuropsychiatric changes, prepare families for the course of illness in patients with either clinical presentation,treat symptomatically with psychotropic medications to help families cope with behaviorally disturbed patients.