Neuropsychiatry of corticobasal degeneration and progressive supranuclear palsy

Abstract

Corticobasal syndrome (CBS) and progressive supranuclear palsy syndrome (PSPS) are two of the atypical Parkinsonism syndromes, in that patients exhibit rigidity, occasional tremor and postural instability, but do not symptomatically respond to dopamine replacement. CBS and PSPS can often present with complex cognitive difficulties and neuropsychiatric disturbances. Symptoms of depression, apathy, or agitation can be subtle and are often overlooked as reactions to learning a new diagnosis of Parkinsonism. These symptoms may be the earliest presenting evidence of CBS or PSPS, and these syndromes can be misdiagnosed with a primary psychiatric disorder rather than a neurodegenerative condition. Patients may be inappropriately treated with antipsychotic medications that exacerbate the extra-pyramidal motor features of the syndromes. When symptoms are considered to comprise a neurodegenerative syndrome, it may be an inaccurate diagnosis as many features of CBS and PSPS not only overlap with each other, but also with other dementia syndromes. This review discusses similarities and differences between the syndromes of CBS and PSPS in terms of neuropsychiatric features. Improved characterization of the clinical syndromes is necessary to better predict underlying pathology. Improved education about these diseases would help patients, caregivers and clinicians to anticipate symptom progression and avoid premature nursing home placement.

Cognition in corticobasal syndrome and progressive supranuclear palsy: A review

“…Changes in behavior and personality, similar to those observed in frontotemporal dementia, are common in CBS . Surprisingly, however, very few studies have examined social cognition systematically.…”

Molecular imaging to track Parkinson's disease and atypical parkinsonisms: New imaging frontiers

“…PSP and corticobasal syndrome (CBS) are common forms of atypical parkinsonism (APS) and, in early stages, can be sometimes quite difficult to diagnose given that they can overlap clinically with PD and other parkinsonian syndromes, including MSA. Previous imaging studies have reported in CBS either asymmetric hypoperfusion or reduced metabolism, mainly in the striatum, as well as parietal and frontal cortex contralateral to the affected limb . CBS may also be variably associated with asymmetric striatal dopamine denervation (e.g., and Cilia and colleagues.…”

“…CBS may also be variably associated with asymmetric striatal dopamine denervation (e.g., and Cilia and colleagues. Similarly, PSP patients may present with a variable pattern of hypometabolism in the fronto‐striatal‐thalamic regions depending on the clinical presentation and progression . Families with mutations in the progranulin gene presented profound imaging changes of asymmetric hypoperfusion on SPECT and parietal atrophy .…”

Frontotemporal lobar degeneration: current perspectives

“…Myoclonus, asymmetric dystonia, alien limb phenomenon, frontal executive dysfunction, and visuospatial deficits are secondary criteria. Episodic memory is relatively preserved as hippocampi and temporal cortices are unaffected 26. Patients with PSP or CBD may develop behavioral disturbances similar to bvFTD or PPA.…”