Rationality around the clock. Sleep and time-of-day effects on guessing game responses

We administer a unique online version of the Guessing Game where subject responses are collected across all 24 hours of the day. While time-of-day itself does not affect guesses, when combined with a trait-level sleepiness measure and previous night sleep, adverse sleep states lead to responses significantly farther from equilibrium. These results have implications for shift workers and others whose constraints or choices lead to adverse sleep parameters. Key Words:

Thoughtful Days and Valenced Nights: How Much Will You Think About the Problem?

Research investigating risk preference has pointed towards motivation and ability as important factors for determining the strength and likelihood of the framing effect. In the current study we explored the influence of individual differences in motivation and ability through circadian rhythm. We predicted that during circadian off-times participants would exhibit stronger framing effects whereas framing effects would be relatively weaker during on-times. Six-hundred and eighty five individuals took part in the study; the findings supported our hypothesis, revealing a diurnal pattern of risk responding that varies across the 24-hour circadian cycle. Key Words:

Naturally-occurring sleep choice and time of day effects on p-beauty contest outcomes

We explore the behavioral consequences of sleep loss and time-of-day (circadian) effects on a particular type of decision making. Subject sleep is monitored for the week prior to a decision experiment, which is then conducted at 8 a.m. or 8 p.m. A validated circadian preference instrument allows us to randomly assign subjects to a more or less preferred time-of-day session. The well-known p-beauty contest (a.k.a., the guessing game) is administered to examine how sleep loss and circadian mismatch affect subject reasoning and learning. We find that the subject responses are consistent with significantly lower levels of iterative reasoning when ‘sleep deprived’ or at non-optimal times-of-day. A non-linear effect is estimated to indicate that too much sleep also leads to choices consistent with lower levels of reasoning, with an apparent optimum at close to 7 hours sleep per night. However, repeated play shows that sleep loss and non-optimal times-of-day do not affect learning or adaptation in response to information feedback. Our results apply to environments where anticipation is important, such as in coordination games, stock trading, driving, etc. These findings have important implications for the millions of adults considered sleep deprived, as well as those employed in shift work occupations. Key Words:

Flying Airplanes: Realizing Circadian Effects (FARCE)

People differ in their diurnal (time-of-day) preferences—some are morning-types and others are evening-types. These differences are explored in a unique experiment design in which subjects are randomly assigned to produce paper airplanes at either 8:00 a.m. or 10:00 p.m. Our results show that evening-types at their more optimal time-of-day (10:00 p.m.) produce planes that fly statistically significantly farther than those produced by morning-types at their more optimal time-of-day (8:00 a.m.). Evidence also indicates that planes produced by evening-types fly straighter. These results have implications for hiring practices and shift work design in aeronautical engineering and aircraft production. Key Words:

Testing the Advantages of Conscious vs. Unconscious Thought for Complex Decisions in a Distraction Free Paradigm

In this study we test predictions from Unconscious Thought Theory (UTT) that unconscious thought will lead to better decision making in complex decision tasks relative to conscious thought. Different from prior work testing this prediction, we use a method of manipulating conscious and unconscious thinking that is free from distraction. Specifically, we use a 3-week protocol to experimentally induce adverse sleep and circadian states, both of which should reduce deliberative, conscious thinking and therefore increase the relative importance of more automatic unconscious processes. Our findings fail to support UTT predictions and instead coalesce with other replication attempts that cast doubt on the superiority of unconscious processing in complex decision making

Sleep Restriction and Circadian Effects on Social Decisions

Our study examines how chronic sleep restriction and suboptimal times-of-day affect decisions in a classic set of social tasks. We experimentally manipulate and objectively measured sleep in 184 young-adult subjects, who were also randomly assigned an early morning or late evening experiment session during which decision tasks were administered. Sleep restriction and suboptimal time-of-day are both estimated to either directly or indirectly (via an impact on sleepiness) reduce altruism, trust, and trustworthiness. We conclude that commonly experienced adverse sleep states, most notably chronic sleep restriction, significantly reduce prosocial behaviors, and can therefore limit benefits from short-term social interactions

Pour Some Sugar in Me: Does Glucose Enrichment Improve Decision Making?

In the current study we explore whether enriching the brain's supply of glucose will improve the quality and speed of decision making. Prior research shows that glucose enrichment supports cognition and more recent research has shown it can improve decision making on some tasks. To test our hypothesis we used a standardized decision inventory and measured response times. The findings show that supplemental glucose improves decision making but only in complex decision tasks. The findings also show that enrichment leads to faster decision response times across decision types

When Is It Going To Happen? How Temporal Distance Influences Processing for Risky–Choice Framing Tasks

In this article we examine how temporal proximity of an event influences decision task processing and, in turn, the likelihood of framing effects. We hypothesized that events occurring in the relatively near future should be more likely to induce the analytic processing style and result in attenuated framing effects. Events occurring in the more distant future should be processed with the holistic style and framing effects should be relatively more pronounced. In Study 1, we assessed how temporal proximity influenced the perceived relevance for an event occurring at different temporal proximities. In Study 2, we tested the influence of temporal proximity using the Asian disease problem. In Study 3, we tested the influence of temporal proximity with a different type of risky–choice decision task and investigated evidence for analytic/holistic processing. The results provide converging support for a temporal–relevance hypothesis

Regret: The Roles of Consistency-Fit and Counterfactual Salience

Four studies examined the role of a decision's consistency with the orientation of the decision-maker in determining regret. In accordance with our consistency-fit model of regret, the consistency of a decision in relation to decision-makers' goals (Experiments 1), mood states (Experiment 3), and personality orientations (Experiments 2 and 4) predicted regret levels such that consistent decisions were less regrettable than decisions that were inconsistent. In Experiment 1, consistent decisions were defined in relation to decision-makers' goals of changing their typical behavior. Results revealed that decisions that were consistent with the goals of changing their typical behavior were less regrettable. In addition, Experiments 2-4 found that the salience of counterfactuals augmented participants' feelings of regret, supporting the view that accessible alternatives to chosen courses of behavior can serve as affective cues. Implications of a consistency-fit view of regret for norm theory, self-regulation and affect as information were discussed