Long-term effects of early life stress on psycho-physiological functions in psychiatric patients

Abstract

Over the past decades, the link between childhood adversities, brain development and various forms of psychopathology has been well established in the literature. This dissertation aims at identifying psychological functions that are altered as a consequence of early life stress (ELS) and may play a mediating role in the development of a psychiatric disorder. In a quasi-longitudinal design, the present project examined a sample of psychiatric patients that reported a particularly high or a particularly low amount of childhood adversities.Across a 1.5 years period, two groups of patients with high and low ELS as well as a low stress healthy control group were examined three times in order to assess measures of stress sensitivity (number of life events and their subjectively experienced stressfulness), negative affect and psychopathology. Moreover, cortical processing of affective pictures was evaluated with magnetoencephalographic recordings. Patients that had experienced a high amount of ELS reported the most stressful life events in the six month prior to the assessments and experienced them as more stressful than patients without a history of ELS and healthy control subjects. Moreover, they exhibited a stable disposition to high levels of negative affect and had more comorbid diagnoses. Overall cortical responses to affective stimuli were dampened in patients as compared to controls while modulation by stimulus content did not seem to be crucially affected. Dampening of cortical responses was more pronounced in high ELS patients than in low ELS patients. Effects remained stable across a period of altogheter 1.5 years.Results indicate lasting effects of ELS on psychological functions in psychiatric patients despite of clinical improvement. Findings are discussed on the basis of the current literature concerning the mediating pathways between ELS and psychopathology.