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Research generally shows that autonomous forms of motivation are associated with higher performance and job satisfaction, whereas controlled forms of motivation are linked to worse outcomes. These relationships are largely based on between-persons data from cross-sectional studies or longitudinal studies with few measurement points. However, motivation quality, performance, and job satisfaction can vary considerably from day to day and from task to task. It is unclear whether and how these experiences and behaviors covary over time within individuals at work in daily life. The present study assessed this using a diary approach. With a default protocol of 30 working days, an ecological momentary assessment application prompted 19 white-collar workers five times a day to report their autonomous and controlled motivation for work tasks and their productivity and job satisfaction at the end of each day. Fourteen participants gathered sufficient data to compute within-person relations and individual networks. At the between-person level, results were somewhat in line with prior survey-based research, whereas results at the within-person level present more nuanced findings and demonstrate that these will not inherently align with previous between-person findings. Individual network analyses indicated considerable interindividual heterogeneity, especially in the relationships between motivation and job satisfaction. In conclusion, these findings point to significant variability in the observed relations between task-related motivation, performance and job satisfaction in everyday life, and highlight the added value of a within person approach and individual networks in addition to between-persons approaches. The implications of these findings for occupational wellbeing research are discussed. [ABSTRACT FROM AUTHOR]

Rationale: Major depressive disorder (MDD) has been associated with disturbances in social functioning and in the brain serotonin system. Reduced levels of serotonin may negatively influence social functioning, for example by impairing the recognition of facial emotion expressions. Objectives: The present study investigated the effect of acute tryptophan depletion (ATD), which reduces brain serotonin, on a related component of social functioning, empathic accuracy (EA), and oxytocin levels. Methods: Individuals with (FH+) and without (FH−) a family history of MDD participated in a randomized, double-blind, crossover study. On two separate test days, participants ingested tryptophan-deficient and nutritionally balanced amino acid mixtures. Six hours later, they performed an EA task, which involved watching videos of people recounting autobiographical emotional events. While watching, participants continuously rated how these people felt during the recounting. Mood state was repeatedly assessed using the Positive Affect and Negative Affect Schedule and a series of visual analogue scales. Blood samples obtained at baseline and 5 h after mixture ingestion were assessed for tryptophan and oxytocin levels. Results: ATD decreased circulating levels of tryptophan and oxytocin. Nevertheless, there were no significant effects of ATD on EA or mood in either FH group. Conclusions: While previous studies have shown that acute reductions in brain serotonin alter the recognition of facial emotion expressions in never-depressed individuals, the present study suggests that empathic abilities may remain unaffected. [ABSTRACT FROM AUTHOR]

Rationale: Exposure to intermittent episodes of social defeat stress can increase drug seeking and leads to intense drug taking in rats. Objectives: This study investigated the consequences of repeated, intermittent social defeat stress on patterns of drug self-administration in rats with access to heroin, cocaine, or a heroin-cocaine combination ('speedball'). Methods: Male Long-Evans rats were either handled (controls) or subjected to 25-min social defeat stress episodes on days 1, 4, 7, and 10 during confrontations with an aggressive resident. Ten days following the last defeat, rats were assessed for locomotor cross-sensitization in response to heroin or cocaine. Animals were then prepared with intrajugular catheters for drug self-administration. Separate groups of controls and defeated rats were examined for self-administration of heroin (experiment 1), a heroin-cocaine combination (experiment 2), or cocaine (experiment 3). Drug self-administration patterns were evaluated using fixed or progressive ratio schedules of reinforcement during limited access sessions or a 24-h unlimited access binge. Results: Rats with a history of intermittent social defeat stress showed sensitized locomotor behavior when challenged with heroin or cocaine relative to controls. During the 24-h binge session, defeated rats escalated cocaine-taking behavior (ca. 110 mg/kg vs. 66 mg/kg in controls), persisted in self-administering cocaine or the heroin-cocaine mixture for more hours, and showed a tendency for increased heroin-cocaine intake, but no effects on heroin taking. Conclusions: A history of social defeat stress seems to preferentially promote escalated intake of cocaine but not heroin, unless a heroin-cocaine combination is available. [ABSTRACT FROM AUTHOR]