Measuring impulsivity in Parkinson’s disease: a correlational and structural neuroimaging study using different tests

Abstract

Background and purpose Impulsivity is an aspect of personality and a major component of multiple neuropsychiatric conditions. In Parkinson’s disease, it has been associated with the expression of impulse control disorders, a highly prevalent non‐motor complication. Even though multiple tests of impulsivity have been used in this context, the impact of test choice has not been addressed. The aim was to evaluate whether different impulsivity measures in Parkinson’s disease share substantial inter‐scale and anatomical correlations or rather mirror different underlying phenomena. Methods In a consecutive sample of 89 Parkinson’s disease patients without impulse control disorders, four common tests were evaluated assessing different aspects of impulsivity: impulsiveness trait, decisions under implicit risk with and without losses, and delay discounting. Correlations among test scores were analysed and each score was used as a regressor in a set of grey matter volume (GMV) voxel‐based morphometry analyses to explore their brain structural correlates. Results No significant correlations were found between the different impulsivity tests. Furthermore, their structural brain correlates were divergent. Impulsiveness trait appeared to be associated with lower GMV in dorsal–lateral prefrontal cortices, implicit risk (with losses) with higher GMV in the left nucleus accumbens and lower left insular GMV, implicit risk (without losses) with higher GMV in the left lingual gyrus and lower GMV in the gyri recti and delay discounting with higher GMV in the left nucleus accumbens. Conclusions In Parkinson’s disease, different impulsivity measures reflect very dissimilar behavioural and brain structural correlates. Our results suggest that parkinsonian impulsivity is not a unitary phenomenon but rather a heterogeneous entity.

Relationships between Personality Traits and Brain Gray Matter Are Different in Risky and Non-risky Drivers

“…They found that, although the experimental group differed from the control group in self-reported impulsivity and risk behavior, the groups did not differ in DDT scores. In another study with Parkinson's disease patients, no relationships were observed between performance on various tasks that measure risk behavior (BART; IGT) and DDT [ 125 ].…”

Predicting Impulse Control Disorders in Parkinson Disease through Incentive Biomarkers

“…Impulsivity and risk taking were evaluated by several measures: the Barratt Impulsiveness Scale (BIS11) for impulsivity as a trait, commission errors on the Psychology Experiment Building Language Continuous Performance Task based on the Conners Continuous Performance Test for motor inhibition, the Kirby Delay Discounting Task (DDT) for delay discounting, the Iowa Gambling Task (IGT) for implicit risk with potential losses, the Balloon Analog Risk Task (BART) for implicit risk without losses, and the Game of Dice Task (GDT) for explicit risk 30 . Details on all the impulsivity evaluations except for the GDT are described elsewhere 31 . The GDT is a task inspired by the IGT and the Rogers Risk Task 32 .…”

“…30 Details on all the impulsivity evaluations except for the GDT are described elsewhere. 31 The GDT is a task inspired by the IGT and the Rogers Risk Task. 32 It was designed to yield explicit risk choices that remain stable and obvious during the task.…”

Imaging the Limbic System in Parkinson’s Disease—A Review of Limbic Pathology and Clinical Symptoms

“…Concerning reward learning in PD per se , abnormal BOLD activity was found in the accumbens during reward anticipation when compared to healthy controls [ 245 ] and learning correlated with BOLD activity in this area, which was impaired by dopaminergic treatment [ 246 ]. Morphological studies reported on the one hand that implicit risk was associated with higher gray matter volume [ 247 ], but on the other hand disinhibition was linked to thinning of the accumbens [ 248 ].…”