2015 Theses Doctoral
How curiosity drives actions and learning: Dopamine, reward, and information seeking
Curiosity drives many of our daily pursuits and interactions; yet, we know surprisingly little about how it works. Here, I harness an idea implied in many conceptualizations of curiosity – that information has value in and of itself. Reframing curiosity as the motivation to obtain reward – where the reward is information – allows me to leverage major advances in theoretical and computational mechanisms of reward-motivated learning. Using willingness to wait, an established measure of reward-motivated behavior, I test the reward value of information, finding that people are more willing to wait for information about which they’re more curious. I then provide new evidence supporting several predictions that emerge from this information-as-reward framework.
In Chapter 1, I examine whether the valence of information affects its reward value, finding an asymmetric effect of positive vs. negative information, with positive valence associated with both enhanced curiosity and enhanced long-term memory for information. I then test an idea drawn from computational and neurobiological accounts of reward learning, which suggest that it is not the absolute value of information that drives learning, but, rather, the gap between the reward expected and the reward received. By asking people to rate both their curiosity about a question and their satisfaction with the answer, I obtain measures of the values of the reward expected (curiosity) and the reward received (satisfaction) and find that the discrepancy between the two – the information prediction error – facilitates learning.
These findings suggest a conceptual correspondence between dopaminergic mechanisms of reward learning and curiosity. Aging is associated with decrements in dopaminergic functioning, but it is unclear whether these deficits extend to curiosity, as few behavioral investigations of curiosity and aging exist. In Chapter 2, I, therefore, sought to explore the effects of aging on curiosity, providing behavioral evidence that curiosity is not diminished in aging, but, rather, that it is enhanced. These findings also revealed that older adults are more likely to wait for more positive information, consistent with existing theories of emotional processing.
In Chapter 3, I sought to test whether the dopaminergic reward system, particularly the striatum, plays a necessary and causal role in curiosity by examining curiosity in patients with Parkinson’s disease, a neurological disorder characterized by dopamine depletion in the striatum and striatal dysfunction. I provide evidence for diminished curiosity in people with Parkinson’s disease, relative to age- and education-matched controls. In particular, I find that participants with Parkinson’s disease are less likely to wait for lower-value rewards, i.e., information about which they’re less curious.
Taken together, these results support the idea that information functions as a reward – much like money or food – guiding choices and driving learning in systematic ways.
- Marvin_columbia_0054D_13092.pdf binary/octet-stream 1.83 MB Download File
More About This Work
- Academic Units
- Thesis Advisors
- Shohamy, Daphna
- Ph.D., Columbia University
- Published Here
- December 30, 2015