Biology subjects

Barack, D. L.

Publications and source records attributed to Barack, D. L..

4 recordsLinked to original sources

bioRxiv2026

Older Adults Forage Broadly for Information Despite Cost

Healthy aging has long been associated with impairments in learning from rewards. However, typical paradigms do not adequately distinguish between being motivated by information to learn about the world and being motivated by rewarding outcomes from our decisions. The present study describes how these distinct motivations guide learning about the environment across the lifespan. Participants (N=169; ages 18-71 [M=39, SD=15.4]) completed a task based on the board game Battleship, making sequential choices about which tile to uncover on a grid with the goal of finding and learning hidden shapes. While older adults performed worse on the task in terms of overall score, their search behavior stabilized earlier. Older adults also preferred to seek information over reward, spreading their choices more widely, making more choices per trial, and acquiring more information per trial. Additionally, older adults showed a persistent reliance on information gained from the outcomes of their choices. These findings suggest that, as individuals age, they prefer to seek information, which earns them fewer points and slows learning but incurs no cost to long-run projected performance. Despite the conventional view linking age with diminished learning, in a complex environment that disentangled information and reward, older adults remained engaged with no projected learning deficits. Our findings challenge assumptions about cognitive decline in aging and reframe information seeking in older adults as a persistent motivational preference that need not serve learning, raising the question of why the drive to seek information intensifies with age even when it confers no advantage.

animal behavior and cognition↗

bioRxiv2023

Information gathering explains decision dynamics during human and monkey reward foraging

Foraging in humans and other animals requires a delicate balance between exploitation of current resources and exploration for new ones. The tendency to overharvest--lingering too long in depleting patches--is a routine behavioral deviation from predictions of optimal foraging theories. To characterize the computational mechanisms driving these deviations, we modeled foraging behavior using a virtual patch-leaving task with human participants and validated our findings in an analogous foraging task in two monkeys. Both humans and monkeys overharvested and stayed longer in patches with longer travel times compared to shorter ones. Critically, patch residence times in both species declined over the course of sessions, enhancing reward rates in humans. These decisions were best explained by a logistic transformation that integrated both current rewards and information about declining rewards. This parsimonious model demystifies both the occurrence and dynamics of overharvesting, highlighting the role of information gathering in foraging. Our findings provide insight into computational mechanisms shaped by ubiquitous foraging dilemmas, underscoring how behavioral modeling can reveal underlying motivations of seemingly irrational decisions.

animal behavior and cognition↗

bioRxiv2021

Signatures of visuospatial information foraging during learning of complex environments

In the real world, making sequences of decisions to achieve goals often depends upon the ability to learn aspects of the environment that are not directly perceptible. Learning these so-called latent features requires seeking information about them, a process distinct from learning about near-term reward contingencies. Prior efforts to study latent feature learning often use single decisions, use few features, and fail to distinguish between reward-seeking and informationseeking. To overcome this, we designed a task in which humans and monkeys made a series of choices to search for shapes hidden on a grid. Reward and information outcomes from uncovering parts of shapes were not perfectly correlated and their effects could be disentangled. Members of both species adeptly learned the shapes and preferred to select informative tiles earlier in trials than rewarding ones, searching a part of the grid until their outcomes dropped below the average information outcome-a pattern consistent with foraging behavior. In addition, how quickly humans learned the shapes was predicted by how well their choice sequences matched the foraging pattern. This adaptive search for information may underlie the ability in humans and monkeys to learn latent features to support goal-directed behavior in the long run.

animal behavior and cognition↗

bioRxiv2018

Neuronal activity in the posterior cingulate cortex signals environmental information and predicts behavioral variability during routine foraging

Animals engage in routine behavior in order to efficiently navigate their environments. This routine behavior may be influenced by the state of the environment, such as the location and size of rewards. The neural circuits tracking environmental information and how that information impacts decisions to diverge from routines remains unexplored. To investigate the representation of environmental information during routine foraging, we recorded the activity of single neurons in posterior cingulate cortex (PCC) in monkeys searching through an array of targets in which the location of rewards was unknown. Outside the laboratory, people and animals solve such traveling salesman problems by following routine traplines that connect nearest-neighbor locations. In our task, monkeys also deployed traplining routines, but as the environment became better known, they diverged from them despite the reduction in foraging efficiency. While foraging, PCC neurons tracked environmental information but not reward and predicted variability in the pattern of choices. Together, these findings suggest that PCC mediates the influence of information on variability in choice behavior.

neuroscience↗