The effect of autonomous and controlled motivation on self-control performance and the acute cortisol response.

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.

The Relationship Between Multidimensional Motivation and Endocrine-Related Responses: A Systematic Review.

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.

DNA methylation of tumour necrosis factor (TNF) alpha gene is associated with specific blood fatty acid levels in a gender-specific manner.

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.

Health-related motivational and behavioral processes associated with DNA methylation of the TNF gene.

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. METHOD: 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 autonomous motivation was weakly but positively associated with TNF methylation (ß = .18, p = .08). Indirect effects were identified in a subsequent step; autonomous motivation was positively associated with fruit consumption (ß = .29, p = .004), negatively associated with smoking (ß = -.22, p = .03), but not associated with physical activity (ß = .10, p = .34). Moreover, TNF methylation was positively associated with lifetime physical activity (ß = .18, p = .08) and negatively associated with smoking (ß = -.23, p = .03). Direct effects of autonomous motivation on DNA methylation did not persist when these indirect effects were included (ß = .09, p = .43). CONCLUSIONS: Results support the idea that autonomous motivation is associated with DNA methylation, albeit indirectly through tobacco consumption. (PsycINFO Database Record (c) 2019 APA, all rights reserved).