The causes and incidence of rotator cuff injuries in patients under the age of 40 has not been clearly established. The present study focuses on a group of 10 male contact athletes with rotator cuff injuries related to trauma sustained during football (ages from 24 to 36 years). Symptoms included pain and dysfunction in all 10 patients and a positive shrug sign in 8 of 10. The diagnoses for these patients were two isolated contusions, five partial-thickness tears, and three full-thickness tears. Surgery was performed on all patients after nonoperative treatment failed. Three partial-thickness tears were arthroscopically debrided. One full-thickness and two partial-thickness tears were repaired using the arthroscopically assisted miniarthrotomy technique. An open repair was performed in two patients. Two isolated rotator cuff contusions were arthroscopically debrided. The average followup was 21 months. Nine of 10 athletes returned to active participation in football, 7 of these at their preinjury levels. The diagnosis of rotator cuff injury should be considered in a contact athlete who has persistent shoulder pain, impingement signs, weakness, and a positive shrug sign. Arthroscopic debridement of the subacromial space followed by debridement or repair of rotator cuff tears, as clinically indicated, resulted in a marked improvement in function and rapid return to sport for these patients.

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In reinforcement learning (RL) tasks, decision makers learn the values of actions in a context-dependent fashion. Although context dependence has many advantages, it can lead to suboptimal preferences when choice options are extrapolated beyond their original encoding contexts. Here, we tested whether we could manipulate context dependence in RL by introducing a secondary task designed to bias attention toward either absolute or relative outcomes. Participants completed a learning phase that involved choices between two (Experiment 1; n = 111) or three (Experiment 2; n = 90) options per trial with complete feedback. Choice options were grouped in stable contexts so that only a small set of the possible combinations were encountered. One group of participants rated how they felt about particular options (Feelings condition), and another group reported how much they expected to win from particular options (Outcomes condition) at occasional points throughout the learning phase. A third group (Control condition) made no ratings. In the subsequent transfer test, participants chose between all possible pairs of options without feedback. The experimental manipulation had no effect on learning phase performance but a significant effect on transfer, with the Feelings and Control conditions exhibiting greater context dependence than the Outcomes condition. Further, rated feelings reflected relative valuation whereas expected outcomes were more sensitive to absolute option values. Hierarchical Bayesian modeling was used to summarize the findings from both experiments. Our results suggest that attending to affective reactions versus expected outcomes moderates the effects of encoding context on subsequent choices.

Previous research on experience-based decisions with complete feedback supports the idea that people generally prefer options that produce better outcomes most of the time. The current study explored whether this preference is modulated by differences in expected value (EV) and the presence or absence of occasional losses. Participants (n = 52) recruited through a crowdsourcing platform completed an online experiment that involved repeated choices between a safer and a riskier option while receiving complete feedback. The riskier option yielded a better outcome on 80% of draws so that choosing it minimized the probability of regret. Preference for the riskier option was high when it had the same EV as the safer option and all outcomes were gains, but it decreased when the safer option had a higher EV and when both options included occasional losses. These findings replicated the results of a preliminary experiment with undergraduate participants (n = 105). Outcome ratings obtained on 50% of trials showed large effects of regret and rejoicing, confirming that participants were sensitive to relative comparisons between obtained and forgone outcomes. Reinforcement-learning modeling indicated that the effects of unequal EVs and mixed outcomes could be accounted for by assuming combined encoding of absolute and relative outcomes and unequal weighting of gains and losses. Overall, our results suggest that minimizing the probability of regret is an important motivational factor in experience-based decisions, but structural features of the choice environment can modulate the extent to which decision makers follow this strategy.

No abstract