Sleep disturbances in the speech-language variant of progressive supranuclear palsy

Spatiotemporal characteristics of neurophysiological changes in patients with four-repeat tauopathies

INTRODUCTION

Progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD), are the most common four-repeat tauopathies (4RT), and both frequently occur with varying degree of Alzheimer's disease (AD) copathology. Intriguingly, patients with 4RT and patients with AD are at opposite ends of the wakefulness spectrum-AD showing reduced wakefulness and excessive sleepiness whereas 4RT showing decreased homeostatic sleep. The neural mechanisms underlying these distinct phenotypes in the comorbid condition of 4RT and AD are unknown. The objective of the current study was to define the alpha oscillatory spectrum, which is prominent in the awake resting-state in the human brain, in patients with primary 4RT, and how it is modified in comorbid AD-pathology.

METHOD

In an autopsy-confirmed case series of 4R-tauopathy patients (n = 10), whose primary neuropathological diagnosis was either PSP (n = 7) or CBD (n = 3), using high spatiotemporal resolution magnetoencephalography (MEG), we quantified the spectral power density within alpha-band (8-12 Hz) and examined how this pattern was modified in increasing AD-copathology. For each patient, their regional alpha power was compared to an age-matched normative control cohort (n = 35).

RESULT

Patients with 4RT showed increased alpha power but in the presence of AD-copathology alpha power was reduced.

CONCLUSIONS

Alpha power increase in PSP-tauopathy and reduction in the presence of AD-tauopathy is consistent with the observation that neurons activating wakefulness-promoting systems are preserved in PSP but degenerated in AD. These results highlight the selectively vulnerable impacts in 4RT versus AD-tauopathy that may have translational significance on disease-modifying therapies for specific proteinopathies.

An Update on Apraxia of Speech

PURPOSE OF REVIEW

Apraxia of speech (AOS) is a motor speech disorder that has long been recognized to occur secondary to acute neurologic insults and, more recently, to neurodegenerative diseases as a harbinger for progressive supranuclear palsy and corticobasal syndrome. This article reviews recent findings regarding the clinic phenotypes of AOS, neuroimaging correlates, and the underlying disease processes.

RECENT FINDINGS

Two clinical subtypes of AOS map onto two underlying 4-repeat tauopathies. New imaging techniques have recently been applied to the study of progressive AOS. There is no data on the impact of behavioral intervention, although studies of nonfluent/agrammatic primary progressive aphasia that include patients with AOS suggest some benefit in speech intelligibility and maintenance. While recent findings suggest subtypes of AOS exist that are linked to molecular pathology and have important implications for disease progression, further research is needed to assess outcome of behavioral and other types of intervention.

The effect of antidepressant therapy on a patient with progressive supranuclear palsy accompanied by depression, anxiety and fluctuating dementia

Progressive supranuclear palsy (PSP) is a complex clinicopathologic disease which can only be definitively confirmed at autopsy. It belongs to a family of conditions exhibiting Parkinson's syndrome, including Lewy body dementia (LBD) or dementia with Lewy body (DLB), and Parkinson's disease dementia (PDD). In regards to clinical manifestations, these two dementias have many overlapping characteristics. The declines of cognition in older patients of dementia are generally accompanied by depression, anxiety, hallucinations, delusions, eating and sleep disorders. This can lead to the difficulty in distinguishing the types of dementia and accurately diagnosing the disease. Herein, we present a complex case of PSP with depression, anxiety, and fluctuating dementia in which DLB was initially suspected. Before antidepressant therapy, the patient showed extrapyramidal symptoms as well as major depression, which lead to greatly impaired movement. Moreover, this patient was an older person with depression disorders, implicating further complexities of late life depression. After two weeks of therapy with antidepressants, the patient had reduced depressive symptoms, and even the somatic symptoms were improved. This case demonstrated that antidepressant therapy can be effective in improving emotion and cognition among patients with late life depression.