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Extant literature consistently demonstrates the level of self-determination individuals experience or demonstrate during an activity can be primed. However, considering most of this literature comes from a period wherein p-hacking was prevalent (pre-2015), it may be that these effects reflect false positives. The aim of the present study was to investigate whether published literature showing autonomous and controlling motivation priming effects contain evidential value or not. A systematic literature search was conducted to identify relevant priming research, while set rules determined which effects from each study would be used in p-curve analysis. Two p-curves including 33 effects each were constructed. P-curve analyses, even after excluding surprising effects (e.g., effects large in magnitude), demonstrated that literature showing autonomous and controlling motivation priming effects contained evidential value. The present findings support prior literature suggesting the effects of autonomous and controlling motivation primes exist at the population level. They also reduce (but do not eliminate) concerns from broader psychology that p-hacking may underlie reported effects.

Background Fatty acids, specifically polyunsaturated fatty acids (PUFAs) play an important role in inflammation and its resolution, however, their interaction with the epigenome is relatively unexplored. Here we investigate the relationship between circulating blood fatty acids and the DNA methylation of the cytokine encoding gene tumour necrosis factor (TNF, OMIM 191160). Methods Using a cross‐sectional study approach, we collected blood samples from adults (N=88 (30 males, 58 females); 18–74 years old) for DNA methylation pyrosequencing analysis at four sites in TNF exon 1 and gas‐chromatography mass‐spectrometry analysis of the fatty acid profile of dried blood spots (DBS). Results Methylation levels of TNF exon 1 are significantly correlated with specific fatty acids in a gender‐specific manner. In the males the PUFAs Docosahexaenoic Acid (DHA) and Arachidonic Acid (AA) were positively associated with TNF methylation, as was the saturated fatty acid (SFA) Stearic Acid; in contrast, mono‐unsaturated fatty acids (MUFAs) had a negative association. In the females, omega‐6 PUFA γ‐Linolenic acid (GLA) was negatively correlated with TNF methylation; Adrenic acid and Eicosadienoic Acid were positively correlated with TNF methylation. Conclusion These results suggest that one way that fatty acids interact with the inflammation is through altered methylation profiles of cytokine genes; thus, providing potential therapeutic targets for nutritional and health interventions., Methylation levels of TNF exon 1 are significantly correlated with specific fatty acids in a gender‐specific manner. In the males the PUFAs Docosahexaenoic Acid (DHA) and Arachidonic Acid (AA) were positively associated. In females, omega‐6 PUFA γ‐Linolenic acid (GLA) was negatively correlated with TNF methylation. These results suggest that one way that fatty acids interact with the inflammation is through altered methylation profiles of cytokine genes; thus, providing potential therapeutic targets for nutritional and health interventions.

Objective: Epigenetics has been described as one of the most exciting areas of contemporary biology, and research has begun to explore whether epigenetic modifications are influenced by psychological processes. The present research explored the associations of health-related motivation and behavior with the DNA methylation of tumor necrosis factor (TNF) gene. Methods: Participants (N =88) completed questionnaires examining engagement with health-related behavior (i.e., physical activity, diet and smoking) and health-related motivation from the perspective of self-determination theory. They also provided a capillary blood sample for DNA extraction and analysis of four CpG sites via bisulfite conversion within exon 1 of TNF. Results: Health-related introjected regulation was not associated with TNF methylation (β =.13, p =.23). Health-related autonomous motivation was weakly but positively associated with TNF methylation (β =.18, p =.08). Indirect effects were identified in a subsequent step; autonomous motivation was positively associated with fruit consumption (β = .29, p = .004), negatively associated with smoking (β = -.22, p =.03) but not associated with physical activity (β = .10, p = .34). Moreover, TNF methylation was positively associated with lifetime physical activity (β = .18, p =.08) and negatively associated with smoking (β =-.23, p =.03). Direct effects of autonomous motivation on DNA methylation did not persist when these indirect effects were included (β =.09, p =.43). Conclusions: Results support the idea that autonomous motivation for health is associated with DNA methylation, albeit indirectly through tobacco consumption.

Autonomously regulated self-control typically does not reduce over time as much, compared with self-control underpinned by controlled motivation. The proposed study tested whether an acute stress response is implicated in this process. Utilizing a framework grounded in self-determination theory, this study examined whether participants' motivational regulation would influence repeated self-control performance and acute stress levels, measured by the stress hormone cortisol. A single-blind randomized experimental design incorporating two motivational conditions (autonomous regulation and controlled regulation) tested these hypotheses. Participants (female = 28; male = 11; Mage = 22.33) performed three sequential self-control tasks; a modified Stroop task followed by two "wall sit" postural persistence tasks. Salivary cortisol was measured at baseline and after each of the wall sits. A repeated measures ANCOVA unexpectedly revealed that participants in the controlled regulation condition recorded greater wall sit performance in the first and second wall sits, compared with the autonomous condition. A repeated measures ANCOVA also revealed a significant quadratic interaction for cortisol. Controlled regulation was associated with an increase, and autonomous regulation condition a decrease, in cortisol that subsided at timepoint two. Results imply autonomous motivation facilitates an adaptive stress response. Performance on the self-control tasks was contrary to expectations, but may reflect short-term performance benefits of controlled motivation.

Multidimensional motivational theories postulate that the type of motivation is as important as the quantity of motivation, with implications for human functioning and well-being. An extensive amount of research has explored how constructs contained within these theories relate to the activation of the endocrine system. However, research is fragmented across several theories, and determining the current state of the science is complicated. In line with contemporary trends for theoretical integration, this systematic review aims to evaluate the association between multidimensional motivational constructs and endocrine-related responses to determine which theories are commonly used and what inferences can be made. Forty-one studies were identified incorporating five distinct motivation theories and multiple endocrine-related responses. There was evidence across several theories that high-quality motivation attenuated the cortisol response in evaluative environments. There was also evidence that motivational needs for power and affiliation were associated with lower and higher levels of salivary immunoglobulin A, respectively. The need for power may play a role in increasing testosterone when winning a contest; however, this evidence was not conclusive. Overall, this review can shape the future integration of motivational theories by characterizing the nature of physiological responses to motivational processes and examining the implications for well-being.