UNIT 4 BRAIN, BEHAVIOUR & EXPERIENCE AREA OF STUDY 2 MENTAL HEALTH
GAMBLING: BIOLOGICAL CONTRIBUTING FACTORS THE DOPAMINE REWARD SYSTEM DOPAMINE REWARD SYSTEM A neural pathway in the brain that, when stimulated, provides feelings of enjoyment and pleasure, which can reinforce and motivate a person to perform certain activities First hypothesised by Canadian neuroscientist James Olds and his student Peter Milner (1954) THE DOPAMINE REWARD SYSTEM INVOLVES THE NEUROTRANSMITTER DOPAMINE
GAMBLING: BIOLOGICAL CONTRIBUTING FACTORS THE DOPAMINE REWARD SYSTEM DOPAMINE REWARD SYSTEM VENTRAL NUCLEUS TEGMENTAL ACCUMBENS AREA (VTA) MEDIAL FOREBRAIN BUNDLE (MFB) AMYGDALA LIMBIC SYSTEM PRE-FRONTAL CORTEX SEPTUM DOPAMINE IS THEREFORE CARRIED TO ALL AREAS OF THIS SYSTEM
GAMBLING: BIOLOGICAL CONTRIBUTING FACTORS RESEARCH FINDINGS ON DOPAMINE ACTIVITY AND PROBLEM GAMBLING Studies with animals have shown that dopamine is released in anticipation of receiving a reward When a reward is unexpected, the release of dopamine immediately after the reward helps to reinforce the remembered association between the reward and any stimulus or response that has preceded it Gray (2007) (pg.672)
GAMBLING: BIOLOGICAL CONTRIBUTING FACTORS RESEARCH FINDINGS ON DOPAMINE ACTIVITY AND PROBLEM GAMBLING Neuroimaging studies have found that games of chance with monetary rewards are powerful activators of the brain’s dopamine reward system DAVID COMINGS & KENNETH BLUM (2000) Developed a theory that certain individuals may be predisposed to developing pathological gambling disorder due to the presence of ‘reward deficiency syndrome’, that is a hypoactive (underactive) dopamine reward system These people do not experience pleasure and enjoyment from everyday activities and therefore seek extraordinary amounts of excitement from gambling TREATMENT OF PARKINSON’S DISEASE Problem gambling may also be due to excessive levels of dopamine Patients treated for Parkinson’s disease take dopamine agonists that increase the levels of dopamine released in the system, or mimic its effects (Levodopa) Studies have found a relationship between the use of dopamine agonists and the development of pathological gambling disorder
GAMBLING: BIOLOGICAL CONTRIBUTING FACTORS THE DOPAMINE REWARD SYSTEM AS A TARGET FOR TREATMENT SOME MEDICATIONS CAN DECREASE THE FREQUENCY OF GAMBLING BEHAVIOUR NALTREXONE has traditionally been used to treat alcohol dependency and addiction to heroin and other opium-based drugs ANTAGONIST:Inhibits the activity of a particular neurotransmitter Inhibiting dopamine activity at the synapse with Naltrexone can result in decreased subjective feelings of pleasure People taking Naltrexone are therefore not compelled to gamble because they do not feel as much pleasure from the act Ingesting Naltrexone can lead to a feeling of satiety, the feeling that you have ‘had enough’ of a behaviour See the study by Suck Won Kim (2001) on page 675
HOMEWORK LEARNING ACTIVITY 16.5 (pg.676)