Dopaminergic state modulates shame and contextual emotional responses in Parkinson's disease

BackgroundShame is frequent in Parkinson's disease (PD) and negatively affects quality of life, yet its dopaminergic modulation remains unclear.MethodsWe investigated the effect of dopaminergic replacement therapy (DRT) on shame in 41 fluctuating PD patients using an experimental tailored shame induction task. At visit 1, participants were presented with 60 short written scenarios (neutral, non-PD-related shame, PD-related shame). A tailored selection of 12 scenarios (4 per category) was generated in three steps: (1) initial rating of all 60 scenarios on a shame/embarrassment visual analogue scale (VAS); (2) selection of the highest-rated scenarios for shame conditions and lowest-rated scenarios for neutral condition to account for individual emotional relevance; and (3) emotional rating of these scenarios on 10 VAS (fear, sadness, disgust, joy, self- and other-directed anger, shame, embarrassment, guilt, stress) to ensure specificity of shame/embarrassment responses. At visits 2 and 3, patients rated the 12 scenarios once ON- and once OFF-DRT (randomized crossover design) using the same 10 VAS.ResultsIn OFF-DRT state, shame ratings were lower than in ON-DRT for non-PD-related shame scenarios (Zratio = -2.53, p = 0.02), with a similar trend for PD-related shame scenarios (Zratio = -2.02, p = 0.06). Conversely, patients reported higher embarrassment (Zratio = 4.53, p < 0.001), stress (Zratio = 3.49, p < 0.001), and self-directed anger (Zratio = 3.99, p < 0.001) when evaluating scenarios rated as neutral in the ON-DRT state.ConclusionsIn OFF-DRT state, emotional responses showed altered contextual calibration, with reduced shame in shame-eliciting contexts and increased negative emotions in neutral situations. These findings suggest that dopaminergic state may modulate intensity and appraisal processes of emotions. Dopamine medication influences shame and emotional responses to situations in Parkinson's diseasePeople living with Parkinson's disease (PwPD) often experience shame, which impacts quality of life. It is unclear how dopamine, a brain chemical affected in PD and partly replaced by medication, influences this emotion.This study aimed to investigate how dopamine affects shame in 41 PwPD experiencing symptom fluctuations over three visits.At visit 1, participants read 60 short scenarios of everyday situations. Some situations were designed to provoke shame, either related or unrelated to PD, while others were emotionally neutral. PwPD rated on a computer scale how much imagining themselves in each situation made them feel shame or embarrassment. Based on these ratings, researchers selected 12 situations for each participant, choosing the most shameful and most neutral ones to match the participant's experiences.At visits 2 and 3: participants rated these 12 situations on 10 emotions (fear, sadness, disgust, joy, anger toward self and others, shame, embarrassment, guilt, and stress). This was done twice: once while on their usual dopaminergic treatment (“ON”) and once after temporarily stopping it (“OFF”).We found that when “OFF” dopamine treatment, participants reported less shame in situations expected to provoke shame. They also reported more embarrassment, stress, and self-directed anger, in situations they had initially considered neutral.These results suggest that when dopamine levels are lower, emotional reactions may become less well matched to the situation. Dopamine might help PwPD interpret emotional situations appropriately.Understanding these emotional changes may help patients, relatives, and healthcare professionals recognize that some feelings experienced when medication is wearing off may be linked to dopamine levels rather than to the situation itself. This could improve communication, reduce misunderstandings, and help doctors adapt treatment by considering emotional symptoms alongside motor symptoms in Parkinson's disease.