Multifeature Mismatch Negativity in Patients With Posttraumatic Stress Disorder

OBJECTIVE

The mismatch negativity (MMN) component of the event-related brain potential has been used to examine auditory monitoring in various mental disorders. Previous research with posttraumatic stress disorder (PTSD) patients has revealed contradictory results. Enhanced as well as diminished MMNs have been obtained.

METHOD

The multifeature protocol was employed to investigate the pattern of MMN in 17 military deployment-related PTSD patients and a group of healthy university student controls.

RESULTS

Our results suggest no general effect of PTSD on the MMN involving the majority of acoustic features. There were slightly reduced MMNs in patients relative to controls for 2 of the features (duration, location). On the other hand, the N1 component was reduced in patients compared with controls.

CONCLUSIONS

Choice of the stimulus protocol might be an important factor to explain inconsistent results in previous research. Differences in the auditory context between stimulus protocols and deficits in the formation of larger (auditory) contexts in PTSD might account for the results.

SIGNIFICANCE

This study adds to the small number of studies on PTSD and MMN and revealed valuable information to guide future, related studies.

Changes in sleep architecture in German Armed Forces personnel with posttraumatic stress disorder compared with depressed and healthy control subjects

BACKGROUND

This study compares the sleep architecture of patients with posttraumatic stress disorder (PTSD) with that of both patients with depression and subjects with no mental disorder.

METHOD

45 German armed forces personnel with PTSD, 72 German armed forces personnel with depression and 24 healthy control subjects underwent 24-hour polysomnography. The effects of group membership, medication and the statistical interaction of group and medication were analysed for the following variables: sleep onset latency, REM sleep latency, slow-wave sleep and REM sleep percentages.

RESULTS

Sleep onset latency was significantly prolonged in both the PTSD and the depression group. Moreover, psychotropic medication was associated with significantly prolonged REM sleep latency.

CONCLUSION

The impact on sleep onset latency is of special clinical relevance in that according to preliminary studies, it is of major importance for subjective sleep quality. In contrast to the other parameters, an increase in sleep onset latency results in a subjective reduction in sleep quality which can lead to hyperarousal and increased preoccupation with sleep, which in turn may lead to dysfunctional sleep patterns.

Aetiology and treatment of nightmare disorder: State of the art and future perspectives

This consensus paper provides an overview of the state of the art in research on the aetiology and treatment of nightmare disorder and outlines further perspectives on these issues. It presents a definition of nightmares and nightmare disorder followed by epidemiological findings, and then explains existing models of nightmare aetiology in traumatized and non‐traumatized individuals. Chronic nightmares develop through the interaction of elevated hyperarousal and impaired fear extinction. This interplay is assumed to be facilitated by trait affect distress elicited by traumatic experiences, early childhood adversity and trait susceptibility, as well as by elevated thought suppression and potentially sleep‐disordered breathing. Accordingly, different treatment options for nightmares focus on their meaning, on the chronic repetition of the nightmare or on maladaptive beliefs. Clinically, knowledge of healthcare providers about nightmare disorder and the delivery of evidence‐based interventions in the healthcare system is discussed. Based on these findings, we highlight some future perspectives and potential further developments of nightmare treatments and research into nightmare aetiology.