The Neural Correlates of Spatial and Object Working Memory in Elderly and Parkinson’s Disease Subjects

This fMRI study deals with the neural correlates of spatial and objects working memory (SWM and OWM) in elderly subjects (ESs) and idiopathic Parkinson’s disease (IPD). Normal aging and IPD can be associated with a WM decline. In IPD population, some studies reported similar SWM and OWM deficits; others reported a greater SWM than OWM impairment. In the present fMRI research, we investigated whether compensated IPD patients and elderly subjects with comparable performance during the execution of SWM and OWM tasks would present differences in WM-related brain activations. We found that the two groups recruited a prevalent left frontoparietal network when performing the SWM task and a bilateral network during OWM task execution. More specifically, the ESs showed bilateral frontal and subcortical activations in SWM, at difference with the IPD patients who showed a strict left lateralized network, consistent with frontostriatal degeneration in IPD. The overall brain activation in the IPD group was more extended as number of voxels with respect to ESs, suggesting underlying compensatory mechanisms. In conclusion, notwithstanding comparable WM performance, the two groups showed consistencies and differences in the WM activated networks. The latter underline the compensatory processes of normal typical and pathological aging.

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Dopaminergic modulation of neural correlates of working memory in Parkinson’s Disease

Basal Ganglia ◽

10.1016/j.baga.2012.01.003 ◽

2012 ◽

Vol 2 (1) ◽

pp. 33-39 ◽

Cited By ~ 1

Author(s):

Eduard Kraft ◽

Ellen Binder ◽

Dorothee Lulé ◽

Alexander Storch ◽

Oliver Gruber

Keyword(s):

Parkinson’S Disease ◽

Working Memory ◽

Parkinson's Disease ◽

Neural Correlates ◽

Dopaminergic Modulation

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Working memory training increases neural efficiency in Parkinson’s disease: a randomized controlled trial

Brain Communications ◽

10.1093/braincomms/fcaa115 ◽

2020 ◽

Vol 2 (2) ◽

Author(s):

Kathrin Giehl ◽

Anja Ophey ◽

Jochen Hammes ◽

Sarah Rehberg ◽

Thorsten Lichtenstein ◽

...

Keyword(s):

Parkinson’S Disease ◽

Working Memory ◽

Parkinson's Disease ◽

Functional Connectivity ◽

Controlled Trial ◽

Memory Task ◽

Neural Correlates ◽

Working Memory Training ◽

Memory Training ◽

Memory Processes

Abstract Impairment of working memory and executive functions is already frequently observed in early stages of Parkinson’s disease. Improvements in working memory performance in this cohort could potentially be achieved via working memory training. However, the specific neural mechanisms underlying different working memory processes such as maintenance as opposed to manipulation are largely under-investigated in Parkinson’s disease. Moreover, the plasticity of these correlates as a function of working memory training is currently unknown in this population. Thus, the working memory subprocesses of maintenance and manipulation were assessed in 41 cognitively healthy patients with Parkinson’s disease using a newly developed working memory paradigm and functional MRI. Nineteen patients were randomized to a 5-week home-based digital working memory training intervention while the remaining patients entered a control, wait list condition. Working memory task-related activation patterns and context-dependent functional connectivity, as well as the change of these neural correlates as a function of training, were assessed. While both working memory processes activated an extended frontoparietal–cerebellar network, only the manipulation of items within working memory also recruited the anterior striatum. The intervention effect on the neural correlates was small, but decreased activation in areas relevant for working memory could be observed, with activation changes correlating with behavioural change. Moreover, training seemed to result in decreased functional connectivity when pure maintenance was required, and in a reorganization of functional connectivity when items had to be manipulated. In accordance with the neural efficacy hypothesis, training resulted in overall reduced activation and reorganized functional connectivity, with a differential effect on the different working memory processes under investigation. Now, larger trials including follow-up examinations are needed to further explore the long-term effects of such interventions on a neural level and to estimate the clinical relevance to potentially delay cognitive decline in cognitively healthy patients with Parkinson’s disease.

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Impairment of the visuospatial working memory in the patients with Parkinson’s Disease: an fMRI study

10.21203/rs.3.rs-120393/v1 ◽

2020 ◽

Author(s):

Shoji Kawashima ◽

Yoko Shimizu ◽

Yoshino Ueki ◽

Noriyuki Matsukawa

Keyword(s):

Parkinson’S Disease ◽

Working Memory ◽

Parkinson's Disease ◽

Functional Neuroimaging ◽

Brain Regions ◽

Common Symptom ◽

Visuospatial Working Memory ◽

Fmri Study ◽

Neuropsychological Characteristics ◽

Normal Ageing

Abstract Background: Mild cognitive impairment (MCI) is a common symptom in the patients with Parkinson’s disease (PD). MCI is a transitional stage between normal ageing and dementia. The neuropsychological characteristics of the PD-MCI are impairment in frontal executive function and/or visuospatial working memory. The newly modified version of the n-back test, visuospatial n-back test can assess both visuospatial recognition and visuospatial working memory. Methods: In this study, we aimed to clarify the advantage of visuospatial n-back test as a tool for the detection of the impairment of working memory in the patients with PD. Using functional MRI, we aimed to search the specific brain regions associated with the impairment of visuospatial working memory. The score of 0-back reflects visuospatial recognition, and the scores of 1-back and 2-back reflect visuospatial working memory. We recruited 13 patients with PD-MCI, and 15 patients with cognitive normal PD (PD-CN). Group comparisons between PD-MCI and PD-CN were performed for three loads of this test. The correlations between the scores of n-back test and task-related activations were analysed for all patients. Results: We found that the correct answer rate of patients with PD-MCI was lower in the 2-back test than those with PD-CN. However, scores of the 0-back and 1-back tests were not different between the groups. The result of fMRI showed that the activations within the middle frontal gyrus (MFG) and the inferior parietal lobule (IPL) during the 2-back test were reduced in the patients with PD-MCI.Conclusions: This study revealed an impaired visuospatial working memory in PD-MCI in association with the reduced activations of MFG and IPL. Combinations of functional neuroimaging and the visuospatial n-back test are beneficial to evaluate the impairment of working memory in PD.

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