Chronic stress has direct effect on difficulty in identifying emotions but the effect is indirect through depression

Abstract

Introduction: Emotional recognition is the identification of basic facial emotions like anger, disgust, fear, and sadness; it is an innate ability that involves perceptual analytical function and emotional processing for both parties in an interaction. Mood disorders like major depression disorder (MDD) and schizophrenia are found to interfere with this process in various levels for various emotions. Knowing that negative experiences and adverse life events are significant precursors for such disorders, we aimed to test the possible relationship between one's own emotional processing and recognition of others' emotions and the level of stress in their life.

Method: 125 college students without any known psychiatric disorder participated to our study (66% female, Mage=20.48∓ 1.84, 18-29). To measure the stress typology, Childhood Trauma Questionnaire (CTQ), Perceived Stress Scale (PSS) and Chronic Stress Scale (CSS) were used. Beck Anxiety Inventory (BAI), Beck Depression Inventory (BDI) were also used as independent measures of stress. To measure emotional processing, Emotion Recognition (ER-40) task of PennCNB, which questioned the recognition of anger, fear, sadness, happiness, and neutral emotional expressions was used and Toronto Alexithymia Inventory (TAI) was also used as a self-report scale to measure awareness of one's own emotions.

Results: There is no correlation between emotion recognition (ER-40 task) scores and stress scales. All stress measurements correlated positively with TAI scores (BAI: pc:0.40, p<0.001, BDI: pc:0.39, p<0.001, PSS: pc:0.29, p=0.001, CSS: pc:0.27, p=0.003). This significance emerged for CSS, PSS, BAI, and BDI (PC scores>0.34, p<0.001) from identifying emotions subdimensions (TAI_identify) and for PSS, BAI, and BDI (PC scores ≥0.28, p≤0.02) from discriminating emotions subdimensions. In linear regression analysis to predict scores in difficulties in identifying emotions sub dimension (TAI_identify), it was found that it is predicted by scores in CSS (p=0.003), when corrected for CTQ, age and gender. As depression can cause deficits in identifying emotions and it is correlated with chronic stress, the role of beck depression level as a mediator of CSS and TAI_identify was investigated by mediation analysis and the output model for the mediation effect of Beck depression level was built. Chronic stress influences TAI_identify scores indirectly through its effect on Beck Depression Inventory score (ab= 0.093, 95% bootstrap CI= 0.036 to 0.179). Chronic stress causes more depression, with greater depression level associated with difficulties identifying emotions (b=0.233, p=0.0001). There was no definitive evidence that chronic stress directly influenced difficulties in identifying emotions independent of BDI (c' =0.069, p=0.122, 95% bootstrap CI=-0.019 to 0.156).

Conclusion: While chronic stress can affect one's identification of one's own emotions, it does not affect the recognition of others' emotions. Previous studies support the role of insula in interoceptive awareness and depression. The mediator role of stress on insula and Major depression disorder-Interoceptive awareness association may be studied in future studies.