The aim of this investigation was to determine the group of symptoms which are the most prominent in depression comorbid to PTSD and to compare delineated features with the similar features of the depressive episode which is a part of the primary major depressive disorder (MDD).

Totally 120 patients were assessed and divided into the experimental (PTSD-depression) and control (depression-only group). The presence and the severity of the disorders were assessed by means of the following instruments: CAPS-DX, MADRS, 17-items HDRS and QIDS-SR. Statistical analysis was performed using ANOVA.

Results showed that symptoms which differed most significantly between the two groups were: sleep disturbances, trouble concentrating, poor apeetite, inner tension, agitation, fatigue and loss of energy, guilt, loss of interest and pleasure and depressed mood.

On the ground of the results obtained we reach the conclusion that depressive symptoms which were followed by PTSD are not the results of the increased activation of the neural circuits by the two pathophysiological processes, but there is the case of differential engagement of neural networks in which stimulation from the lower brain structures responsible for generation of emotional input, increasingly arrives into the upper brain structures, in which the more intense and deeper emotional processing takes place causing more intense experience of emotional stimuli and bridging the connection from perceptual and cognitive contents up to affective and visceral center of the organismus.