How is variability in physiological responses to social stress related to punishment and reward sensitivities? Preliminary findings from the revised reinforcement sensitivity theory of personality perspective.

OBJECTIVE: Although personality traits are assumed to have biological/physiological foundations, research has yielded mixed evidence regarding the relationship between personality and physiological stress responses. Moreover, the field has often overlooked the contemporary neuroscience-based personality approach, known as the Reinforcement Sensitivity Theory (RST) of Personality, in stress research. METHOD: The present study examined the relationship between the revised RST's personality dimensions and heart rate and skin conductance level (SCL) in response to the Trier Social Stress Test in a sample of 61 healthy university students. RESULTS: Piecewise latent growth curve analysis controlling for the participants' current life stress, smoking use, and caffeine intake revealed that individuals with higher behavioral inhibition exhibited higher physiological reactivity, whereas those with high reward sensitivity showed smaller heart rate reactivity. The behavioral disengagement facet of the behavioral inhibition scale was associated with reduced sympathetic arousal during the stress task. Additionally, reward interest was associated with a larger recovery of SCL. CONCLUSION: Results were generally in line with the revised theory. The study findings were discussed within the paradigm of the approach-avoidance conflict and highlighted the importance of reward sensitivity in stress resilience.

Comparison of blood levels of vitamin B12, folic acid, riboflavin, and homocysteine in keratoconus and healthy subjects.

PURPOSE: To evaluate blood levels of vitamin B12, folic acid, riboflavin, and homocysteine in keratoconus (KC) and healthy subjects. SETTING: Eskisehir Osmangazi University, Eskisehir, Turkey. DESIGN: Cross-sectional study. METHODS: 100 KC patients (patient group) between the ages of 18 to 35 years and 200 healthy individuals (control group) in the same age range were included in the Eskisehir Osmangazi University Hospital Eye Clinic between October 2019 and March 2020. In all cases, a complete ophthalmologic examination and corneal tomography evaluation with a Pentacam Scheimpflug camera were performed. In blood samples, vitamin B12 and folic acid levels were measured using an electrochemiluminescence immunoassay analyzer, and homocysteine and riboflavin levels were measured using high-performance liquid chromatography. Chi-square tests were used in the analysis of categorical variables, and Mann-Whitney U and Kruskal-Wallis tests were used in the analysis of numerical variables. RESULTS: Homocysteine (13.0 ± 6.6 vs 12.1 ± 5.4 µmol/L, P = .190), vitamin B12 (313.5 ± 119.4 vs 322.9 ± 128.3 pg/mL, P = .619), and folic acid (7.0 ± 2.7 vs 7.4 ± 2.9 ng/mL, P = .230) levels were not different between KC (100 eyes of 100 subjects) and control (200 eyes of 200 subjects) groups. The mean riboflavin level was 84.0 ± 21.8 µg/L in the patient group and 183.6 ± 74.3 µg/L in the control group, with a significant difference between the 2 groups ( P < .001). Riboflavin levels were below 180 µg/L in 99% (n = 99) of the cases in the KC group and 53.5% (n = 107) in the control group ( P < .001). CONCLUSIONS: Low blood riboflavin levels in KC patients may be a possible risk factor in the pathogenesis of KC.

Religiosity, Identity Confusion, and Psychological Well-Being in Turkish University Students: The Moderating Role of Religious Orientation.

Research conducted in industrialized democracies where Christianity is the prevailing religion has suggested that religiosity may play an important role in identity development and well-being. This study examined the associations between religiosity, religious orientation, identity confusion, and psychological well-being in 488 Turkish university students. The results revealed that extrinsic religious orientation was positively associated with identity confusion. On the other hand, religiosity, extrinsic religious orientation, and identity confusion were negatively associated with psychological well-being, while intrinsic religious orientation was positively associated with psychological well-being. Moderation analysis indicated that extrinsic religious orientation could facilitate psychological well-being in the midst of severe identity confusion.

The influence of corneal geometrical and biomechanical properties on tonometry readings in keratoconic eyes.

PURPOSE: To identify the effect of corneal geometrical and biomechanical parameters on the intraocular pressure (IOP) measurements obtained by Goldmann Applanation Tonometer (GAT), non-contact tonometer, iCare Pro Rebound Tonometer (IRT), Tonopen and Ocular Response Analyzer (ORA, Goldmann-correlated IOP: IOPg, corneal compensated IOP: IOPcc). METHODS: We prospectively recruited patients with a tomographically confirmed diagnosis of keratoconus. IOP measurements were performed in the following order: non-contact tonometry, ORA, IRT, GAT and Tonopen. The means of the three IOP measurements were used for the analysis. Correlation analyses were performed to assess the association between tonometer readings and the corneal geometrical and biomechanical parameters including ORA waveform parameters. Tonometer variability was assessed using a stepwise linear regression analysis. RESULTS: Fifty-one patients with keratoconus (27 females, mean age 30.8 ± 8.7 years) were evaluated. The highest mean IOP was measured by IOPcc (14.6 ± 2.3 mmHg) followed by IRT IOP (13.0 ± 3.2 mmHg), Tonopen IOP 12.0 ± 2.6 mmHg), GAT IOP (11.7 ± 3.1 mmHg), NCT IOP (10.2 ± 3.2 mmHg) and IOPg (10.2 ± 3.6 mmHg). NCT and IOPg were affected from all corneal parameters including thickness, curvature and biomechanical parameters. While GAT and IRT had significant correlations with corneal resistance factor (CRF) and corneal hysteresis, IOPcc only had a significant correlation with CRF. None of the corneal factors had any statistically significant correlation with Tonopen. CRF predicted tonometer measurement variability in 7 of the 15 inter-device variability assessments. CONCLUSION: Tonopen was the least affected from the corneal parameters followed by IOPcc and GAT. CRF was a strong determinant of tonometer variability.