Altruistic Punishment is punishing violators of social norms when there is personal cost.
The test: whether or not to punish the financial advisor.
The subjects: (1) Control group of people without Parkinson’s disease (PD) (26)
(2) People with PD, with impulsive-compulsive behaviours (ICB), on dopamine meds (14)
(3) People with PD, with ICB, off dopamine meds (13)
(4) People with PD, without ICB, on dopamine meds (14)
(5) People with PD, without ICB, off dopamine meds (12)
Results: (1) PD patients without ICB on and off dopamine punished more often than controls
(2) PD patients with ICB punished more than controls, when they were on dopamine
(3) PD patients with ICB punished equal to controls, when they were off dopamine
Conclusion: Dopamine has a role in punishment decisions in PD patients with ICB
Altruistic Punishment has been shown to reduce unjust behaviour within groups. Functional
Imaging shows that the brain area responsible for mediating punishment is the caudate nucleus in the
dorsal striatum, and altruistic punishment is specialized in the ventral caudate. Also, the prefrontal
cortex is responsible for processing fair and unfair behaviours.
In PD, dopamine innervation of dopamine is depleted. This leads to rigidity and bradykinesia
(difficulty with motor movements). Patients with PD don’t experience pleasure. Some PD patients who
need to undergo long-term dopamine treatment experience biological ICB (pathological gambling,
hypersexuality, binge eating, and reckless generosity) because dopamine provokes this behavior. A
study showed that there is a positive association between impulsivity and altruistic punishment.
Authors were motivated to pursue this research because they believed that PD+ICB patients
were less likely to punish because they may be less sensitive to aversive aspects of the lack of
reciprocation of trust. As well, since impulsivity is not a norm, they might not feel a greater need to
punish violators of the norm. The main hypothesis of this research is that any PD patient would punish
more than controls because dopamine replenishment in the striatum would cause greater intensity in
Patients and Methods
The controls were from the family of the PD patients. PD patients were those