Impulsivity and Compulsivity After Subthalamic Deep Brain Stimulation for Parkinson’s Disease

Abstract

Impulsivity and compulsivity are prominent non-motor problems in Parkinson's disease (PD). Despite 20 years of research, there is still an ongoing debate as to whether subthalamic deep brain stimulation (STN DBS) for PD exacerbates or improves these symptoms. Here, we review how STN DBS affects clinical symptoms and neurocognitive aspects of impulsivity and compulsivity. When comparing patients post-to pre-surgery, in the majority of studies STN DBS for PD is associated with a decrease in clinically diagnosed impulse-control disorders and disorders of compulsivity. To avoid confounds, such as post-surgical decreases in dopaminergic medication doses, comparisons can also be made between DBS "On" versus "Off" conditions. These experimentally assayed effects of STN DBS with respect to neurocognitive aspects of impulsivity and compulsivity are more mixed. STN DBS improves behavioral flexibility without impairing negative feedback learning, delay discounting, or inhibitory control, as long as stimulation is restricted to the dorsal STN. However, STN DBS may drive impulsive actions when a subject is faced with competing choices. We discuss how motivated responses may be either enhanced or impaired by STN DBS depending on engagement of dorsal or ventral STN-mediated circuits. Future studies should combine structural and functional circuit measures with behavioral testing in PD patients on and off medication and stimulation. A more sophisticated understanding of how to modulate corticostriatal-thalamo-cortical loops will increase the likelihood that these circuit manipulation techniques can successfully be applied to a wider range of neuropsychiatric disorders.

Predictors of short-term impulsive and compulsive behaviour after subthalamic stimulation in Parkinson disease

“…Consistent with previous studies, we did not find an effect of the preoperative motor score (UPDRS-III) on postoperative ICB changes. 8 Moreover, we found that lower LEDD-DA was a predictor for greater improvement in QUIP-RS total score. A possible explanation might be that patients with higher tendency to develop ICB, may be unable to tolerate higher doses of DA, 36 37 perhaps prompting surgical evaluation.…”

Clinical neuroscience and neurotechnology: An amazing symbiosis

“…The hypothesis that ventral STN might be dedicated to cognitive functions and dorsal STN to motor functions ( Jahanshahi et al., 2015 ) stems from the observation that prefrontal cortical areas project to the former, whereas motor and premotor cortices project to the latter ( Haynes and Haber, 2013 ). This observation has been corroborated by the effects on DBS outcome of the location of the target stimulation in the dorsoventral/occipitorostral axis of the STN ( Greenhouse et al., 2013 ; Scherrer et al., 2020 ; van Wouwe et al., 2017 , 2020 ).…”

Impulse control disorders in Parkinson’s disease

“…Retrospektywne badania prowadzone w małych grupach chorych dawały szeroki zakres rezultatów -od poprawy objawów z kręgu ICD po implantacji systemu DBS, poprzez brak wpływu zabiegu DBS-STN, po pogorszenie lub rozwój ICD de novo (Kim et al, 2013). W ostatnich latach opublikowano jednak wiele prospektywnych badań randomizowanych wskazujących na korzystne oddziaływanie DBS-STN na zmniejszenie objawów ICD (Scherrer et al, 2020). Jeszcze mniej jasny wydaje się wpływ na rozwój ICD implantacji DBS do części wewnętrznej gałki bladej (internal globus pallidus, DBS-GPi), aczkolwiek w nielicznych opublikowanych do tej pory doniesieniach obserwowano tylko pojedyncze przypadki rozwoju tego schorzenia po wszczepieniu DBS-GPi (Moum et al, 2012).…”