Ochsner Clinic in New Orleans The facility is now known as the Ochsner Medical Center.
Archives of Neurology Richard L. Strub, “Frontal Lobe Syndrome in a Patient with Bilateral Globus Pallidus Lesions,” Archives of Neurology 46, no. 9 (1989): 1024–27.
“to get up in the morning” Michel Habib, “Athymhormia and Disorders of Motivation in Basal Ganglia Disease,” The Journal of Neuropsychiatry and Clinical Neurosciences 16, no. 4 (2004): 509–24.
movement and emotion emerge This is how Mauricio Delgado, a neurologist at Rutgers, describes the striatum: “The striatum is the input unit of a larger structure, the basal ganglia. I say the input unit because it receives connections from different brain areas which subserve distinct brain functions—putting the striatum in a prime position to influence behavior. The basal ganglia and in turn the striatum are very important in facets of behavior related to motor (deficits in this structure is common in Parkinson’s patients), cognitive and motivation. One line of thinking regarding the striatum and its role in motivation and more specifically reward processing is that it is involved in learning about rewards and using that information to make decisions that help guide behavior, updating the brain along the way whether a reward is better or worse than prior expectations.”
regulating our moods Oury Monchi et al., “Functional Role of the Basal Ganglia in the Planning and Execution of Actions,” Annals of Neurology 59, no.2 (2006): 257–64; Edmund T. Rolls, “Neurophysiology and Cognitive Functions of the Striatum,” Revue Neurologique 150 (1994): 648–60; Patricia S. Goldman-Rakic, “Regional, Cellular, and Subcellular Variations in the Distribution of D1 and D5 Dopamine Receptors in Primate Brain,” The Journal of Neuroscience 15, no. 12 (1995): 7821–36; Bradley Voytek and Robert T. Knight, “Prefrontal Cortex and Basal Ganglia Contributions to Working Memory,” Proceedings of the National Academy of Sciences of the United States of America 107, no. 42 (2010): 18167–72.
motivation had disappeared For my understanding of how brain injuries influence behavior, I am indebted to Julien Bogousslavsky and Jeffrey L. Cummings, Behavior and Mood Disorders in Focal Brain Lesions (Cambridge: Cambridge University Press, 2000).
striatal injuries Parkinson’s frequently involves injuries to the substantia nigra, a region that communicates with the striatum. R. K. B. Pearce et al., “Dopamine Uptake Sites and Dopamine Receptors in Parkinson’s Disease and Schizophrenia,” European Neurology 30, supplement 1 (1990): 9–14; Philip Seeman et al., “Low Density of Dopamine D4 Receptors in Parkinson’s, Schizophrenia, and Control Brain Striata,” Synapse 14, no. 4 (1993): 247–53; Philip Seeman et al., “Human Brain D1 and D2 Dopamine Receptors in Schizophrenia, Alzheimer’s, Parkinson’s, and Huntington’s Diseases,” Neuropsychopharmacology 1, no. 1 (1987): 5–15.
see a computer screen Mauricio R. Delgado et al., “Tracking the Hemodynamic Responses to Reward and Punishment in the Striatum,” Journal of Neurophysiology 84, no. 6 (2000): 3072–77.
expectation and excitement In some versions of this experiment, participants were rewarded for guessing right and penalized for guessing wrong with small financial winnings. In response to a fact-checking email, Delgado provided further context for the experiments: “The goal of that initial study was to investigate the human reward circuit. That is, we know from animal research that certain brain regions were important for processing information about reward. We knew less about how that translated to the human brain and how it translated to more common human rewards such as money, which had implications to behavioral addictions such as pathological gambling. Thus, with the guessing game, our initial goal was to compare what happened in the brain when participants received a monetary reward (for a correct guess) and a monetary punishment or loss (for an incorrect guess). The pattern we observe is very characteristic of a reward response. We see activity in the striatum (both dorsal and ventral parts). The response is an initial increase at the beginning of the trial when the question mark appears and they make a guess. We reasoned that it reflected anticipation of a potential reward. Other work using this task (see Delgado et al. 2004, Leotti and Delgado 2011) support that as does the work by Brian Knutson (2001). They don’t know yet if their guess is correct and lead to a reward or incorrect and lead to a loss. So the increase is common for both types of trials. Once the outcome is revealed, we see an interesting pattern where the striatum differentiates between a positive and negative outcome—a gain or a loss. It is increased for a gain and decreased response for a loss. One interpretation of this finding was that the striatum was coding for the value of an outcome. A more global interpretation that takes into account all the neural inputs and outputs of this structure is that it takes in information about the outcome/reward, it matches up with the expectations (e.g., was the outcome better or worse than expected—if you guessed high was the card high, or did you make the wrong guess) and allows for the system to update and inform the next decision (e.g., maybe try low next time).”