Brian Anderson - US grants

DESCRIPTION (provided by applicant): Attention selects which aspects of sensory input are brought to awareness. Because attention is a limited resource, which stimuli are attended has important implications for effective goal- directed behavior, survival, and well-being. Attentional selection can proceed in voluntary fashion, according to context-specific goals. At the same time, however, certain kinds of stimuli receive attentional processing involuntarily, overriding goal-directed attention allocation. Such stimuli are said to capture attention. It is well establised that physically salient stimuli capture attention, and that ongoing priorities influence attentiona selection involuntarily through contingent attentional capture. Recently, my colleagues and I have shown that valuable stimuli, previously associated with the delivery of reward, also capture attention involuntarily, independently of salience and ongoing priorities. We have referred to this phenomenon as value-driven attentional capture, and the proposed project will investigate the mechanisms by which learned value influences attentional priority in this way. Aim 1 will probe the mechanisms of selection in value-driven capture using human eye tracking. Through Aim 2, the neural mechanisms of value-driven capture will be assessed using functional magnetic resonance imaging (fMRI), and Aim 3 will investigate the role of value-driven capture in drug addiction. The results will provide a better understanding of the ways in which reward learning influences attentional priority, which represents one of the most critical roles that attention plas in promoting survival. Although attention to reward-predicting stimuli will often be adaptive, it can also become maladaptive when attention to rewarding stimuli conflicts with ongoing goals. In this way, the proposed project will also have important implications for clinical syndromes in which both attention and reward have been critically implicated, including drug addiction, obesity, obsessive-compulsive disorder, and attention-deficit/hyperactivity disorder; these implications will be explored directly in Aim 3. Finally, the proposed project will provide outstanding cutting-edge training in cognitive neuroscience, neuroimaging methodology, and related technical skills, and will continue to develop my strong background in behavioral psychophysics. This award will provide support to complete my dissertation research and prepare me for the next step in my scientific career. PUBLIC HEALTH RELEVANCE: The proposed project investigates the role of reward learning in involuntary attention allocation. Attending to rewarding stimuli is a critical function of the human brain; several clinical conditions, including drug addiction, obesity, obsessive-compulsive disorder, and attention- deficit/hyperactivity disorder, are characterized by disorders of cognitiv control that are thought to involve disordered reward learning. This project will contribute to the basic-research foundations for clinical research into the causes and treatments of these conditions. The findings of the proposed project will also speak to the mechanisms by which people attend to and are distracted by stimuli in their environment, which has public safety implications for issues such as distraction while driving.

PROJECT SUMMARY/ABSTRACT Attention selects which aspects of sensory input receive cognitive processing and thereby influence behavior. Drug addiction alters the attentional system, resulting in prominent attentional biases towards drug cues. Such drug-related attentional biases are related to the broader phenomenology of addiction, including craving and relapse. There has been long-standing interest in implementing attentional bias measures in clinical settings, either as a predictive measure to inform treatment decisions or as a target of treatment. However, a major barrier to the realization of this goal is that current means of assessing these biases are not sufficiently precise to support clinical utility, which has stifled progress in this area. Mirroring this complexity, and underscoring the need for clarity, debate has arisen concerning the role of learning history in the guidance of attention more broadly. Persistent attentional biases have been linked to reward history, learning from aversive outcomes, and outcome-independent selection history (e.g., familiarity). Emerging accounts of such experience-dependent attentional biases disagree about the nature of the underlying mechanism(s) involved. If we do not understand the variety of influences of learning history on attention at a fundamental level, how can we understand how these influences contribute to addiction-related attentional biases? The proposed research directly addresses this need by identifying, isolating, and measuring multiple hypothesized components of the attentional biases that characterize addiction, providing the precision necessary for more accurate predictions of patient outcomes and more targeted efforts to improve these outcomes through attentional bias modification. Specific Aim 1 will distinguish between common and distinct attentional priority signals arising from reward learning and reward-independent selection history, probing both the cognitive and neural mechanisms underlying each of these sources of priority. Specific Aim 2 will identify the cognitive profile and neural mechanisms underlying attentional biases attributable to aversive conditioning, which together with Specific Aim 1 will provide a comprehensive picture of the multifaceted nature of experience-dependent attention. The overarching goal of the proposed research is to characterize multiple distinct components of experience-dependent attentional bias that contribute to attentional biases evident in drug-dependent individuals. These fundamental components of attentional bias will provide a much more precise window into the attentional processes that are relevant to our understanding of addiction than existing measures can offer. It is anticipated that the knowledge gained from the proposed research with provide a foundation for overcoming fundamental limitations in the clinical utility of attentional bias measures, allowing for fruitful exploration of this aspect of addiction in the context of improving assessment and treatment.