Browsing by Subject "Cognitive neuroscience"

This dissertation presents three essays on topics in development economics. Drawing on rich longitudinal data as well as measures of cognitive skills adapted from cognitive neuroscience, the chapters focus on health and human capital through the life course. The first essay isolates the causal impact of public health insurance on child health, measured by height-for-age, by exploiting the roll-out of Seguro Popular, a large-scale program that provides public health insurance to about half of Mexico’s population. Drawing on insights from the biology of human linear growth and using population-representative longitudinal data, we establish that Seguro Popular has had a modest impact on child nutritional status. These effects were larger after the program had been established for several years, suggesting that supply-side factors may have been critical impediments. The second essay turns to the relationship between executive function and labor market outcomes. This project describes how a widely used measure of executive function with foundations in cognitive neuroscience was implemented as part of a large-scale, population-representative survey in Indonesia. I find that higher cognitive functioning is associated with rewards in the labor market, particularly for women, and that executive function is related to labor force participation and the choice between wage work and self-employment. Motivated by the importance of executive function and human capital in later life, the third essay turns to the relationship between parental executive functioning and child outcomes. I find that parental executive function is strongly related to child executive function, and that better parental executive function is associated with better child nutritional outcomes, as measured by height-for-age and weight-for-height. The relationship between parents’ executive functioning and child outcomes depends both on the gender of the child and whether the child is first born or has older siblings. These results suggest that the relationships I observe between parental executive functioning and child development are not simply genetic but reflect parental choices and behaviors. Together, these chapters demonstrate the importance of bringing the tools from cognitive neuroscience to economics to further examine the role that specific cognitive skills like executive function play for success and well-being. They also highlight the critical importance of the early childhood household and environment for development, with long-lasting consequences for later life.

The research studies presented as this dissertation constitute a methodologically diverse and conceptually integrative approach to understanding impulsiveness in the context of cognitive control and decision making. Broadly, these findings address the validity of current conceptions of trait impulsiveness, relationships between those traits and brain or laboratory measures of cognitive control, and links between impulsive traits and economic decisions under conditions of delay or uncertainty. The findings presented in this thesis affirm the multidimensional nature of impulsiveness as a construct, and link individual differences in specific impulsive types to behavioral and neurobiological measures of control function. The nature of motor, attentional, and nonplanning impulsive types are contextualized by reference to evidence supporting a broad theory of behavioral control based on hierarchical organization of action, ranging from concrete acts to abstract plans and strategies. We provide evidence linking concrete forms of urgent/motor impulsiveness to behavior and brain activation during response-related control, and more abstract and future-oriented premedititative/nonplanning impulsiveness to strategic control signals in more rostral PFC. Finally, these findings are complemented by causal evidence from a neurostimulation study linking a contextual control network to risky decision making and attentional impulsiveness.

Emotion is known to influence multiple aspects of memory formation, which may include the initial encoding of the memory trace, its consolidation over time, and the efficacy of its retrieval. However, prior investigations have tended to treat emotional modulation of episodic memory as a unitary construct, thus conflating the contributions of these different stages to emotion-mediated memory enhancements. The present thesis aims to disentangle the component processes of emotional memory formation and retrieval through a series of studies using cognitive behavioral and functional magnetic resonance imaging (fMRI) methods. In the first 2 studies, neural activity was evaluated during the initial viewing of emotionally arousing and neutral scenes and, in the 3rd study, neural activity during this initial viewing period was compared to that during a recognition memory task. The findings are compatible with the proposal that two distinct networks support successful emotional memory formation: an amygdala-medial temporal lobe (MTL) network that modulates the consolidation of memories over time and a prefrontal-MTL network that translates emotion effects on controlled elaboration into superior memory encoding. The superlative quality of emotional memories is furthermore marked by heightened similarity between neural states at encoding and retrieval, suggesting another line of evidence through which emotion effects can be observed. Taken together, the results presented here highlight the heterogeneity of processes that confer mnemonic advantages to emotionally significant information.

Cognitive neuroscience is an interdisciplinary enterprise aimed at explaining cognition and behavior. It appears to be succeeding. What accounts for this apparent explanatory success? According to one prominent philosophical thesis, cognitive neuroscience explains by discovering and describing mechanisms. This "mechanist thesis" is open to at least two interpretations: a strong metaphysical thesis that Carl Craver and David Kaplan defend, and a weaker methodological thesis that William Bechtel defends. I argue that the metaphysical thesis is false and that the methodological thesis is too weak to account for the explanatory promise of cognitive neuroscience. My argument draws support from a representative example of research in this field, namely, the neuroscience of decision-making. The example shows that cognitive neuroscience explains in a variety of ways and that the discovery of mechanisms functions primarily as a way of marshaling evidence in support of the models of cognition that are its principle unit of explanatory significance.

The inadequacy of the mechanist program is symptomatic of an implausible but prominent view of scientific understanding. On this view, scientific understanding consists in an accurate and complete description of certain "objective" explanatory relations, that is, relations that hold independently of facts about human psychology. I trace this view to Carl Hempel's logical empiricist reconceptualization of scientific understanding, which then gets extended in Wesley Salmon's causal-mechanistic approach. I argue that the twin objectivist ideals of accuracy and completeness are neither ends we actually value nor ends we ought to value where scientific understanding is concerned.

The case against objectivism motivates psychologism about understanding, the view that understanding depends on human psychology. I propose and defend a normative psychologistic framework for investigating the nature of understanding in the mind sciences along three empirically-informed dimensions: 1) What are the ends of understanding? 2) What is the nature of the cognitive strategy that we deploy to achieve those ends; and 3) Under what conditions is our deployment of this strategy effective toward achieving those ends? To articulate and defend this view, I build on the work of Elliot Sober to develop a taxonomy of psychologisms about understanding. Epistemological psychologism, a species of naturalism, is the view that justifying claims about understanding requires appealing to what scientists actually do when they seek understanding. Metaphysical psychologism is the view that the truth-makers for claims about understanding include facts about human psychology. I defend both views against objections.