Is amygdala size correlated with stress?

Background: One of the important mechanisms that regulate the stress response of the body is hypothalamic pituitary adrenal axis. One of the structures activating this axis is amygdala. We have seen people around who react calmer and cooler to very stressful situations. Are people with smaller amygdala really calmer? Or, can we say that the bigger the amygdala, which is the trigger of the body’s response to stress, the more a person panics? Aim of the study is to compare the saliva cortisol levels and amygdala volume.Materials and methods: Study conducted with 63 male students. Magnetic resonance images of students were taken before their final exam to calculate amygdala volumes. Saliva samples of all students were taken two times to detect cortisol levels in saliva. First one was 20 days before the final exam and second one was on the exam day. We assumed that the students were stressful on exam day.Results and Conclusions: No statistically significant correlation was found between saliva cortisol levels and amygdala volume in the study

Landslide susceptibility mapping in an area of underground mining using the multicriteria decision analysis method

Landslides are geomorphological phenomena that affect anthropogenic and natural features on the Earth’s surface. Many previous studies have identified several factors that have contributed to landslides. Among these factors are physical characteristics, such as slope, aspect, and land cover, of Earth’s surface. Moreover, landslides can be triggered by human activities such as underground mining. This study aims to identify landslide susceptibility areas by analyzing landslide-related factors, including land subsidence triggered by underground mining. The area of interest was Kozlu, Turkey, where underground mining has been in progress for the past 100 years. Thus, to identify landslide risk zones, the multicriteria decision analysis method, together with the analytical hierarchy method, was used. The datasets included were topography, land cover, geological settings, and mining-induced land subsidence. The spatial extent of land subsidence was estimated using a previously published model. A landslide susceptibility map (LSM) was developed using a purposely developed GIS-based software. The results were compared with a terrain deformation map, which was developed in a separate study using the differential synthetic aperture radar interferometry (DInSAR) technique. The results showed a substantial correlation between the LSM and DInSAR map. Furthermore, it was found that ~ 88% of the very high and high landslide risk areas coincided with location of the past landslide events. These facts suggest that the algorithm and data sources used were sufficient to produce a sufficiently accurate LSM, which may be used for various purposes such as urban planning. © 2018, The Author(s)

The effect of stress-induced cortisol increase on the sense of ankle proprioception

Objectives: The aim of this study is to analyze the effect of stress-induced cortisol increase on the sense of ankle proprioception. Patients and methods: Between April 2016 and May 2016, a total of 60 students (30 males, 30 females; mean age: 19.2±1.5 years; range, 19 to 20 years) from İnönü University, Faculty of Medicine, Department of Freshmen were included in the study. Separate measurements were made for the right and left ankle to make ankle proprioception measurements a month before the committee exam during their relaxed period using a device designed with digital inclinometer. The sense of ankle proprioception was measured at 10° dorsiflexion (DF), 11° plantar flexion (PF), and 25° PF angles with open eyes and closed eyes using active reproduction test. Salivary samples were taken for stress assessment and State Trait Anxiety Inventory-I (STAI-I) was conducted. The same tests were repeated on the day of committee exam. Results: Test results showed no statistically significant difference between the right and left ankle proprioception measurements of 10° DF, 11° PF, and 25° PF angles with open eyes (p>0.05). However, a statistically significant difference was found between the right and left ankle proprioception scores at the same angles with closed eyes (p<0.05). According to the Wilcoxon analysis conducted for the comparison of the relaxed and stressed periods of cortisol and STAI-I inventory, a statistically significant difference was found (p<0.05). The Spearman’s Rho analysis showed no significant correlation between the right and left ankle proprioception scores and cortisol and STAI-I with open eyes, while there was a statistically significantly positive direction and low correlation between the same angles with closed eyes. Conclusion: Our study results show that the increase in the stress-related cortisol is negative for the ankle proprioception sense. © 2019 by Turkish Society of Physical Medicine and Rehabilitation

Christmas dinner [2]

Group photo of Davich family at Christmas dinner, DavichKendall Webb Collectio