PURPOSE OF REVIEW: @entity73 that occur even early in the course of @entity191 have received increasing attention in current imaging research. The exact physio-pathological processes mediating the deficits and the complex relationship of cognitive signs and antiparkinsonian treatment are not well understood. A clearer understanding of these mechanisms could potentially influence treatment choices, drug development and, ultimately, @entity1 care. RECENT FINDINGS: Abnormal networks identified in studies of resting state metabolism in @entity191 represent metabolic markers for remote effects of striato-nigral degeneration. These metabolic changes include subcortico-cortical networks, in particular cognitive cortico-striato-pallidal-thalamocortical loops. Recent brain studies focus on intervention-related brain changes. They illustrate different task-specific changes in brain activation with deep brain stimulation and with levodopa. Variable results of stimulation can be attributed to different effects on segregated cortico-striato-pallidal-thalamocortical loops during stimulation. By contrast, the heterogeneity observed in studies with levodopa possibly reflects the disease-stage and task-specific effects of levodopa. A decline in caudate @entity935 modulated basal ganglia outflow appears to contribute to @entity409 and to brain activation changes in these loops at early @entity195 stages, while mesocortical degeneration mediated increases of inefficient dorsolateral prefrontal cortex activation may display a feature of more @entity1442 stages only. SUMMARY: Despite evidence for the role of @entity935 and cortico-striato-pallidal-thalamocortical loops in cognition, the specific contributions of mesocortical @entity935 depletion and striatal dysfunction with downstream consequences on the loops remain to be separated. Additionally, more research is needed into the role of non-dopaminergic pathology in @entity73 in @entity191 .

Functional imaging of cognition in XXXX .

@entity1 :: ('9606', 'Species') :: ['patient'] @entity935 :: ('MESH:D004298', 'Chemical') :: ['dopamine'] @entity73 :: ('MESH:D003072', 'Disease') :: ['Cognitive deficits', 'cognitive decline'] @entity409 :: ('MESH:D008107', 'Disease') :: ['executive dysfunction'] @entity191 :: ('MESH:D010300', 'Disease') :: ["Parkinson's disease"] @entity1442 :: ('MESH:D020178', 'Disease') :: ['advanced disease'] @entity195 :: ('MESH:D000544', 'Disease') :: ["Parkisnon's disease"]
@entity191 :: (MESH:D010300,Disease) :: ['Parkinson's disease']
