Inhibitory framing in hypersexual patients with Parkinson's disease. An fMRI pilot study

The relationship between Parkinson's disease and sexual hyperactivity secondary to drug treatment: A systematic review

INTRODUCTION

This review addresses the prevalence of hypersexual behavior in Parkinson's patients and the underlying neurobiological mechanisms, identifying risk and protective factors, comparing incidence among different treatments, and proposing recommendations for management and prevention.

OBJECTIVE

To conduct a review on the relationship between Parkinson's disease and hypersexual behavior as a result of pharmacological treatment.

METHODOLOGY

The search strategy, guided by PRISMA and PICOS criteria, focuses on the correlation between Parkinson's disease and hypersexual behavior due to pharmacological treatment. Utilizing databases like PubMed and Proquest, studies from the last 10 years in English or Spanish were selected, emphasizing clinical trials with Parkinson's patients under treatment. Inaccessible, irrelevant, or mixed-sample studies were excluded. The Cochrane Scale assessed the risk of bias.

RESULTS

Out of 122 records, 103 remained after eliminating duplicates; 48 were reviewed, and ultimately, 6 studies met the inclusion criteria for analysis.

CONCLUSIONS

Synthesizing the risk and protective factors linked to hypersexual behavior in Parkinson's patients receiving pharmacological treatment underscores the critical need for early detection and incorporation of these factors into clinical care. The suggested guidelines for managing and preventing hypersexual behavior in these patients carry substantial practical implications.

Neural network localization in Parkinson's disease with impulse control disorders

Background

There is a huge heterogeneity of magnetic resonance imaging findings in Parkinson's disease (PD) with impulse control disorders (ICDs) studies. Here, we hypothesized that brain regions identified by structural and functional imaging studies of PD with ICDs could be reconciled in a common network.

Methods

In this study, an initial systematic literature review was conducted to collect and evaluate whole-brain functional and structural magnetic resonance imaging studies related to PD with ICDs. We subsequently utilized the Human Connectome Project (HCP) dataset (n = 1,093) and a novel functional connectivity network mapping (FCNM) technique to identify a common brain network affected in PD with ICDs.

Results

A total of 19 studies with 25 contrasts, incorporating 345 individuals with PD and ICDs, and 787 individuals with PD without ICDs were included in the analysis. By using the HCP dataset and a novel FCNM technique, we ultimately identified that the aberrant neural networks predominantly involve the default mode network (middle and inferior temporal gyrus, anterior cingulate cortex, angular gyrus) and subcortical network (caudate nucleus).

Conclusion

This study suggests that the heterogeneous neuroimaging findings in PD with ICDs can be attributed to shared abnormalities in the default mode and subcortical networks. These dysfunctions are associated with impaired self-regulation, decision-making, and heightened impulsivity in PD with ICDs. Our findings integrate diverse neuroimaging results from previous studies, providing a clearer understanding of the neurobiological mechanisms underlying PD with ICDs at a network level.

Imaging of impulse control disorders in Parkinson's disease

Impulse control disorders (ICD) are frequent and cumbersome behavioral disorders in patients with Parkinson's disease (PD). Understanding their pathophysiological underpinnings is crucial. Molecular imaging using positron emission tomography (PET) and single-photon emission computed tomography (SPECT) clearly indicates preexisting vulnerability and abnormal sensitization of the pre- and postsynaptic dopaminergic system. Functional magnetic resonance imaging (fMRI) studies reveal abnormal connectivity within the reward system involving the ventral striatum and orbitofrontal cortex. These alterations pinpoint the dysfunction of reinforcement learning in ICD, which is biased toward the overvaluation of reward and underestimation of risk, and the deficit in inhibitory control mechanisms related to abnormal connectivity within and between the limbic and the associative and motor networks.

Imaging the Limbic System in Parkinson's Disease-A Review of Limbic Pathology and Clinical Symptoms

The limbic system describes a complex of brain structures central for memory, learning, as well as goal directed and emotional behavior. In addition to pathological studies, recent findings using in vivo structural and functional imaging of the brain pinpoint the vulnerability of limbic structures to neurodegeneration in Parkinson's disease (PD) throughout the disease course. Accordingly, dysfunction of the limbic system is critically related to the symptom complex which characterizes PD, including neuropsychiatric, vegetative, and motor symptoms, and their heterogeneity in patients with PD. The aim of this systematic review was to put the spotlight on neuroimaging of the limbic system in PD and to give an overview of the most important structures affected by the disease, their function, disease related alterations, and corresponding clinical manifestations. PubMed was searched in order to identify the most recent studies that investigate the limbic system in PD with the help of neuroimaging methods. First, PD related neuropathological changes and corresponding clinical symptoms of each limbic system region are reviewed, and, finally, a network integration of the limbic system within the complex of PD pathology is discussed.