Attenuation of the Köhler Effect in Racially Dissimilar Partnered Exercise Reversed Using Team Identity Strategy.

The authors describe two research experiments exploring the influence of race on the Köhler motivation gain effect with exercise tasks. Experiment 1 tested whether partner racial dissimilarity affects individual performance. Experiment 2 created a team identity recategorization intervention to potentially counter the influence on performance observed in Experiment 1. White male participants were partnered with either a Black or Asian partner (Experiment 1) or with a Black partner utilizing team names and shirt colors as a team identity recategorization strategy (Experiment 2). Racially dissimilar dyads completed two sets of abdominal plank exercises with a Köhler conjunctive task paradigm (stronger partner; team performance outcome dependent upon the weaker-ability participant's performance). The results of Experiment 1 suggest attenuation of the previously successful group motivation gain effect in the racially dissimilar condition. The simple recategorization strategy utilized in Experiment 2 appeared to reverse motivation losses under conjunctive-task conditions in racially dissimilar exercise dyads.

Group dynamics motivation to increase exercise intensity with a virtual partner.

BACKGROUND: The effect of the Köhler group dynamics paradigm (i.e., working together with a more capable partner where one's performance is indispensable to the team outcome) has been shown to increase motivation to exercise longer at a strength task in partnered exercise video games (exergames) using a software-generated partner (SGP). However, the effect on exercise intensity with an SGP has not been investigated. The purpose of this study was to examine the motivation to maintain or increase exercise intensity among healthy, physically active middle-aged adults using an SGP in an aerobic exergame. METHODS: Participants (n = 85, mean age = 44.9 years) exercised with an SGP in a 6-day cycle ergometer protocol, randomly assigned to either (a) no partner control, (b) superior SGP who was not a teammate, or (c) superior SGP as a teammate (team score was dependent on the inferior member). The protocol alternated between 30-min continuous and 4-min interval high-intensity session days, during which participants could change cycle power output (watts) from target intensity to alter distance and speed. RESULTS: Mean change in watts from a targeted intensity (75% and 90% maximum heart rate) was the primary dependent variable reflecting motivational effort. Increases in performance over baseline were demonstrated without significant differences between conditions. Self-efficacy and enjoyment were significantly related to effort in the more intense interval sessions. CONCLUSION: Under these conditions, no Köhler effect was observed. Exercise performance during the higher-intensity interval format is more closely related to enjoyment and self-efficacy beliefs compared to the continuous sessions.

Should jurors be allowed to discuss trial evidence before deliberation?: New research evidence.

Traditionally, jurors are not permitted to discuss trial evidence with one another prior to jury deliberation. Allowing such discussions, at least in civil trials, is a jury innovation that has become increasingly popular. Prior field research has generally supported the assumption that this innovation is benign and, in particular, introduces no systematic bias in jury verdicts. These issues are examined again here within an experimental jury simulation study. The opportunity for predeliberation juror discussion (PJD) between the plaintiff and defense cases-in-chief was manipulated. The results revealed that PJD biased jury verdicts. The nature of this bias was not, as commonly suspected, a commitment to evidence heard prior to PJD, but rather a greater weight placed on evidence heard following the PJD. One good explanation of this bias was that jurors acted as if evidence heard prior to PJD had "already been covered" during the PJD, and so primary attention was given to post-PJD evidence in jury deliberations. Little evidence was found to corroborate several other purported benefits or drawbacks of PJD. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Intergroup Competition in Exergames: Further Tests of the Köhler Effect.

OBJECTIVE: We examined how competing with a software-generated partner (SGP) against another human/virtual partner team, in an exercise video game (exergame), affects individual motivation as measured by effort. MATERIALS AND METHODS: Participants (n = 90; 49 female; Mage = 19.93 ± 1.48) were randomly assigned to one of three conditions: individual control (IC); conjunctive partner, no competition (PNC); or conjunctive partner, with competition (PWC). Participants performed the first series of exercises alone. After resting, those in the partnered conditions performed the remaining trials with a same-sex SGP. Those in the PWC condition were told that they and their virtual partner would be competing against another human-virtual partner team. RESULTS: A significant motivation gain was observed in both partnered conditions compared to control (P < 0.001), but the partnered groups did not differ significantly. However, participants in the PWC condition enjoyed the task significantly (P < 0.05) more than those in the PNC and IC conditions and the PWC participants identified more with the SGP as a teammate than the PNC participants. CONCLUSIONS: Altogether, intergroup competition with an SGP may be an enjoyable way to enhance motivation and performance while exercising.

Introductory Dialogue and the Köhler Effect in Software-Generated Workout Partners.

OBJECTIVES: This study explored the Köhler motivation gain effect utilizing adults and software-generated partners (SGPs) during an abdominal exercise regimen and compared the type of participant-SGP introductory dialogue as a moderator. The Köhler effect applies interdependent team dynamics in which group performance is dependent upon the weaker member. The third objective was to examine if this motivation paradigm would result in adverse consequences to secondary variables: exertion, enjoyment, and self-efficacy beliefs. DESIGN: Adults (Mage = 38.8 +/- 7.7) were randomly assigned to 1 of 3 conditions: Interactive Partner SGP (IP), Linear Dialogue Partner SGP (LDP), or individual control (IC), to complete a series of abdominal exercises. The experiment used a 3 (condition) x 2 (gender) ANCOVA design, with a baseline block of exercises as a covariate. METHOD: Participants completed abdominal exercises individually and, after a rest, repeated the same exercises with either an SGP programmed to be moderately stronger or individually (IC). Prior to the second exercise block, IP participants interacted with the SGP using a dialog tree optional-response format. The LDP participant introduction was a linear, scripted exchange of basic information. RESULTS: The LDP and IP conditions persisted significantly longer than IC, generating moderate effect sizes (d = .62; d = .76). The mean difference between partnered conditions was not significant. CONCLUSIONS: The Köhler motivation exercise paradigm resulted in a considerable increase in persistence (Madj = 28.9, SE = 10.6) in the first study to use middle-aged adults with superior SGPs. Differences between introductory dialogue methods were not significant.

Sleep Deprivation Impairs and Caffeine Enhances My Performance, but Not Always Our Performance.

What effects do factors that impair or enhance performance in individuals have when these individuals act in groups? We provide a framework, called the GIE ("Effects of Grouping on Impairments and Enhancements") framework, for investigating this question. As prominent examples for individual-level impairments and enhancements, we discuss sleep deprivation and caffeine. Based on previous research, we derive hypotheses on how they influence performance in groups, specifically process gains and losses in motivation, individual capability, and coordination. We conclude that the effect an impairment or enhancement has on individual-level performance is not necessarily mirrored in group performance: grouping can help or hurt. We provide recommendations on how to estimate empirically the effects individual-level performance impairments and enhancements have in groups. By comparing sleep deprivation to stress and caffeine to pharmacological cognitive enhancement, we illustrate that we cannot readily generalize from group results on one impairment or enhancement to another, even if they have similar effects on individual-level performance.

Simulated Partners and Collaborative Exercise (SPACE) to boost motivation for astronauts: study protocol.

BACKGROUND: Astronauts may have difficulty adhering to exercise regimens at vigorous intensity levels during long space missions. Vigorous exercise is important for aerobic and musculoskeletal health during space missions and afterwards. A key impediment to maintaining vigorous exercise is motivation. Finding ways to motivate astronauts to exercise at levels necessary to mitigate reductions in musculoskeletal health and aerobic capacity have not been explored. The focus of Simulated Partners and Collaborative Exercise (SPACE) is to use recently documented motivation gains in task groups to heighten the exercise experience for participants, similar in age and fitness to astronauts, for vigorous exercise over a 6-month exercise regimen. A secondary focus is to determine the most effective features in simulated exercise partners for enhancing enjoyment, self-efficacy, and social connectedness. The aims of the project are to (1) Create software-generated (SG) exercise partners and interface software with a cycle ergometer; (2) Pilot test design features of SG partners within a video exercise game (exergame), and (3) Test whether exercising with an SG partner over 24-week time period, compared to exercising alone, leads to greater work effort, aerobic capacity, muscle strength, exercise adherence, and enhanced psychological parameters. METHODS/DESIGN: This study was approved by the Institutional Review Board (IRB). Chronic exercisers, between the ages 30 and 62, were asked to exercise on a cycle ergometer 6 days per week for 24 weeks using a routine consisting of alternating between moderate-intensity continuous and high-intensity interval sessions. Participants were assigned to one of three conditions: no partner (control), always faster SG partner, or SG partner who was not always faster. Participants were told they could vary cycle ergometer output to increase or decrease intensity during the sessions. Mean change in cycle ergometer power (watts) from the initial continuous and 4 min. interval sessions was the primary dependent variable reflecting work effort. Measures of physiological, strength, and psychological parameters were also taken. DISCUSSION: This paper describes the rationale, development, and methods of the SPACE exergame. We believe this will be a viable intervention that can be disseminated for astronaut use and adapted for use by other populations.

Enhancing Aerobic Exercise with a Novel Virtual Exercise Buddy Based on the Köhler Effect.

OBJECTIVE: Research on active videogames (AVGs) has demonstrated the motivation-boosting power of the Köhler effect (a motivating force for "weak links" in groups based on group principles of upward social comparison and indispensability) with software-generated partners (SGPs), but the effect has yet to be examined over time. We tested the viability of the Köhler effect in an AVG with an SGP over 12 exercise sessions using a cycle ergometer and whether a fatiguing partner (FP) could further boost the effect. MATERIALS AND METHODS: A repeated-measures design was used to assess mean changes in exercise persistence over time. Participants were randomly assigned to one of three game conditions: AVG alone (individual-control [IC]), AVG with a consistently superior partner (CSP), or AVG with a superior partner who showed signs of fatigue (FP). Assessments were conducted on 82 participants (42 college students and 40 adults from the community) in a laboratory over 12 experimental sessions. The main outcome measure was exercise persistence (minutes of gameplay cycling at 75% HRmax). RESULTS: Data yielded significant improvements in exercise duration for men in the FP condition when compared with men in the IC condition (Mdiff = 12:32 minutes, SEdiff = 4:54). Women showed no change in exercise persistence over time and no condition differences. CONCLUSION: Exercising in an AVG with a superior SGP, who shows signs of fatigue over time, improved exercise persistence for men but not for women under present experimental conditions.

Cyber Buddy Is Better than No Buddy: A Test of the Köhler Motivation Effect in Exergames.

OBJECTIVE: Although exergames are popular, few people take advantage of the potential of group dynamics to motivate play (and achieve associated health benefits). One motivation gain phenomenon has shown promise for motivating greater effort in partnered exergames: The Köhler effect (working at a task with a more capable partner where one's performance is indispensable to the group). This article examines whether a Köhler effect can be demonstrated in an exergame by exercising with a moderately superior humanoid, software-generated partner. MATERIALS AND METHODS: Male and female (n=120; mean age, 19.41 years) college students completed a series of plank exercises using "CyBuddy Exercise," a program developed specifically for this study. In a lab in an academic building, participants completed the exercises individually and, after a rest, were randomly assigned to complete the same exercises again, but with a "live" human partner (HP) presented virtually, a nearly-human-like, humanoid partner (NHP), a hardly human-like, software-generated partner (HHP), or a no-partner control condition (IC), with equal numbers in each group (i.e., n=30). Exercise persistence, perceived exertion, self-efficacy beliefs, enjoyment, and intentions to exercise were recorded and analyzed. RESULTS: A 4×2 analysis of variance on the (Block 2 - Block 1) difference scores showed that a significant Köhler motivation gain was observed in all partner conditions (compared with IC), but persistence was significantly greater with HPs than with either NHP or HHP humanoid partners (P<0.05). By the conclusion of the study, there were no significant differences among the partnered conditions in perceived exertion, self-efficacy, enjoyment, or future intentions to exercise. CONCLUSIONS: These results suggest that a software-generated partner can elicit the Kohler motivation gain in exergames, but not as strongly as a partner who is thought to be human.

Silence is golden: effect of encouragement in motivating the weak link in an online exercise video game.

BACKGROUND: Despite the physical and mental health benefits, few adults meet US Department of Health and Human Services physical activity guidelines for exercise frequency, intensity, and duration. One strategy that may increase physical activity duration is exercising with an Internet partner (ie, someone who is virtually present, as in video chat). Internet partners help people overcome many barriers associated with face-to-face exercise groups (eg, time, coordinating schedules, social physique anxiety). Past research examining individual performance in groups suggests that an increase in effort occurs when performing a task conjunctively, ie, when a participant is (1) less capable than fellow group members, and (2) participants efforts are particularly indispensable for group success (ie, where the group's potential productivity is equal to the productivity of its least capable member). This boost in effort is more commonly known as the Köhler effect, named after the German psychologist who first observed the effect. While encouragement between group members is common practice in face-to-face group exercise, the effect of encouragement between partners exercising conjunctively across the Internet is unknown. OBJECTIVE: To examine the impact of exercising alone, compared to exercising conjunctively with an Internet partner, both with and without encouragement, on exercise persistence (primary outcomes) and secondary psychosocial outcomes (self-efficacy, enjoyment, exercise intention). METHODS: Participants were recruited online and face-to-face from the campus of Michigan State University. With the assistance of the experimenter, participants (n=115) played an exercise video game in a laboratory, performing a series of five abdominal plank exercises where they were asked to hold the plank for as long as possible (Time 1). They were then randomized to a condition (Individual, Partner-without-encouragement, or Partner-with-encouragement), where they performed the exercises again (Time 2). The impact of condition on the primary outcome measures and secondary outcome measures were evaluated using a 2 (Gender) x 3 (Condition) ANOVA on change scores (Time 2-Time 1). RESULTS: Those who exercised in online teams (n=80) exercised significantly longer (time=78.8s, P<.001) than those who worked individually (n=35). However, exercise duration was shorter when one's more capable partner gave verbal encouragement (n=55) than when s/he did not (n=25) (a mean difference of 31.14s). These increases in effort were not accompanied by altered task self-efficacy, enjoyment of the task, or intention to exercise in the future. CONCLUSIONS: Exercising conjunctively with an Internet partner can boost one's duration of exercise. However, encouragement from the stronger to the weaker member can mitigate these gains, especially if one perceives such comments being directed at someone other than themselves. To boost exercise duration, Internet-based physical activity interventions involving group interaction should make relative abilities of participants known and communication clear.

Aerobic exercise is promoted when individual performance affects the group: a test of the Kohler motivation gain effect.

BACKGROUND: A key barrier to achieving recommended intensity and duration of physical activity is motivation. PURPOSE: We investigated whether a virtually present partner would influence participants' motivation (duration) during aerobic exercise. METHOD: Fifty-eight females (M(age) = 20.54 ± 1.86) were randomly assigned to either a coactive condition (exercising alongside another person, independently), a conjunctive condition (performance determined by whichever partner stops exercising first) where they exercised with a superior partner, or to an individual condition. Participants exercised on a stationary bike at 65 % of heart rate reserve on six separate days. RESULTS: Across sessions, conjunctive condition participants exercised significantly longer (M = 21.89 min, SD = ±10.08 min) than those in coactive (M = 19.77 min, SD = ± 9.00 min) and individual (M = 10.6 min, SD = ±5.84 min) conditions (p < 0.05). CONCLUSION: Exercising with a virtually present partner can improve performance on an aerobic exercise task across multiple sessions.

Is My Exercise Partner Similar Enough? Partner Characteristics as a Moderator of the Köhler Effect in Exergames.

OBJECTIVE: Recent research has shown the Köhler motivation gain effect (working at a task with a more capable partner where one's performance is indispensable to the group) leads to greater effort in partnered exercise videogame play. The purpose of this article was to examine potential moderators of the Köhler effect by exploring dissimilarities in one's partner's appearance, namely, having an older partner (compared with a same-age partner) and having a heavier-weight partner (compared with a same-weight partner). SUBJECTS AND METHODS: One hundred fifty-three male and female college students completed a series of plank exercises using the "EyeToy: Kinetic™" for the PlayStation(®) 2 (Sony, Tokyo, Japan). Participants first completed the exercises individually and, after a rest, completed the same exercises with a virtually present partner. Exercise persistence, subjective effort, self-efficacy beliefs, enjoyment, and intentions to exercise were recorded and analyzed. RESULTS: A significant Köhler motivation gain was observed in all partner conditions (compared with individual controls) such that participants with a partner held the plank exercises longer (P<0.001) and reported higher subjective effort (P<0.01). These results were unmoderated by partner's age and weight, with one exception: Males tended to persist longer when paired with an obese partner (P=0.08). CONCLUSIONS: These results suggest that differences in age and weight do not attenuate the Köhler effect in exergames and may even strengthen it.

Buddy up: the Köhler effect applied to health games.

The present investigation examined the Köhler motivation gain effect in a health game using an absent partner, presented virtually. The Köhler effect occurs when an inferior team member performs a difficult task better in a team or coaction situation than one would expect from knowledge of his or her individual performance. The effect has been strongest in conjunctive task conditions in which the group's potential productivity is equal to the productivity of its least capable member. Participants were randomly assigned to one of four conditions (individual control, coaction, additive, and conjunctive) in a 4 (conditions) • 2 (gender) factorial design and performed a series of isometric plank exercises within an exercise game. They performed the first series of five exercises alone holding each position for as long as they could, and, after a rest period, those in the partner conditions were told they would do remaining trials with a same-sex virtual partner whom they could observe during their performance. The partner's performance was manipulated to be always superior to the participant's. Results showed that task persistence was significantly greater in all experimental conditions than in the individual control condition. The conjunctive condition was no more motivating than either the additive or coactive conditions. Results suggest that working out with virtually present, superior partners can improve persistence motivation on exercise game tasks.

Fertility and intergroup bias in racial and minimal-group contexts: evidence for shared architecture.

Recent research has shown that White women's bias against Black men increases with elevated fertility across the menstrual cycle. We demonstrate that the association between fertility and intergroup bias is not limited to groups defined by race, but extends to group categories that are minimally defined, and may depend on the extent to which women associate out-group men with physical formidability. In Study 1, Black and White women with strong associations between the racial out-group and physical formidability displayed greater bias against out-group men as conception risk increased. Study 2 replicated these results in a minimal-group paradigm. These findings are consistent with the notion that women may be endowed with a psychological system that generates intergroup bias via mechanisms that rely on categorization heuristics and perceptions of the physical formidability of out-group men, particularly when the costs of sexual coercion are high.

Psychological mechanisms underlying the Köhler motivation gain.

Sometimes group work conditions lead to motivation gains rather than to social loafing. Two theoretical explanations for the Köhler motivation gain effect are identified, one stressing social comparison and a second stressing the indispensability of one's effort to the group. The results of three new experiments are reported. Experiment 1 suggested that both explanations are valid and contribute to the Köhler effect. Prior studies suggested that there might be gender differences in the relative importance of these two explanatory processes. Experiment 2 confirmed this suggestion. In Experiment 3, the gender difference was eliminated by priming women with a goal (viz., competition) presumed to be chronically more important to men. It is argued that the relative importance of these two motivational processes will depend on the immediate and chronic importance attached to more personal (viz., to achieve a favorable social comparison) versus collective (viz., to contribute to one's group) goals.

Chaos in the courtroom reconsidered: emotional bias and juror nullification.

A widespread presumption in the law is that giving jurors nullification instructions would result in "chaos"-jurors guided not by law but by their emotions and personal biases. We propose a model of juror nullification that posits an interaction between the nature of the trial (viz. whether the fairness of the law is at issue), nullification instructions, and emotional biases on juror decision-making. Mock jurors considered a trial online which varied the presence a nullification instructions, whether the trial raised issues of the law's fairness (murder for profit vs. euthanasia), and emotionally biasing information (that affected jurors' liking for the victim). Only when jurors were in receipt of nullification instructions in a nullification-relevant trial were they sensitive to emotionally biasing information. Emotional biases did not affect evidence processing but did affect emotional reactions and verdicts, providing the strongest support to date for the chaos theory.

Group performance and decision making.

Theory and research on small group performance and decision making is reviewed. Recent trends in group performance research have found that process gains as well as losses are possible, and both are frequently explained by situational and procedural contexts that differentially affect motivation and resource coordination. Research has continued on classic topics (e.g., brainstorming, group goal setting, stress, and group performance) and relatively new areas (e.g., collective induction). Group decision making research has focused on preference combination for continuous response distributions and group information processing. New approaches (e.g., group-level signal detection) and traditional topics (e.g., groupthink) are discussed. New directions, such as nonlinear dynamic systems, evolutionary adaptation, and technological advances, should keep small group research vigorous well into the future.

"Me versus just us versus us all" categorization and cooperation in nested social dilemmas.

In its generic form, a social dilemma poses a conflict between private and collective interests. People are often faced, however, with a conflict between private, (sub)group, and collective interests. This study examines participants' simultaneous weighing of these 3 nested interests. The results show that increasing the salience of social categorization of any level of the hierarchy (i.e., 6 individuals, 2 subgroups. 1 collective) increases participants' concern for and contributions to the corresponding level of interest (Experiment 1). One can promote concern for and contributions to the collective interest, which are lowest under categorization as 2 subgroups, by individuating the members of the individuals' own subgroup and/or the opposing subgroup (Experiment 2) and by cross-categorization with the opposing subgroup (Experiment 3).

Knowledge of partner's ability as a moderator of group motivation gains: an exploration of the Köhler discrepancy effect.

O. Köhler (1926, 1927) found that less able performers tried harder as team members under conjunctive task demands (Kohler motivation gain effect) and that the greatest gain occurred with moderately discrepant coworker abilities (Köhler discrepancy effect). Recent investigations have reproduced Köhler's overall motivation gain but not the discrepancy effect. The present research examined whether workers' foreknowledge of task abilities--present in Kohler's research, absent in contemporary studies--moderates the discrepancy effect. Participants worked alone or in 2-person teams under conjunctive task demands. Experiment 1 manipulated foreknowledge of ability. Experiment 2 manipulated discrepancy: a (confederate) teammate performed slightly, moderately, or substantially better. Both experiments found (a) overall motivation gains and (b) discrepancy moderation under foreknowledge conditions. Implications for understanding group motivation gains are discussed.

Satisficing in hypothesis generation.

Research in hypothesis generation suggests that people might act as satisficers and be less likely to generate plausible alternative hypotheses when they already have a hypothesis that accounts for the data in hand. Three experiments simulated scientific hypothesis development. In all 3, participants who had been given a hypothesis consistent with available data generated proportionally fewer of the simplest alternative hypotheses than participants given no such satisficing hypothesis. Furthermore, participant satisficing occurred regardless of whether the provided hypothesis was generated a priori or post hoc and despite high incentives for completeness. Limitations and implications of these findings are discussed for hypothesis development and the practice of taking post hoc hypotheses suggested by one's results and presenting them as a priori hypotheses.