Are Alterations in Alpha Synchrony Discriminatory of PTSD?

Research Paper Title

Alterations in Sleep EEG Synchrony in Combat-Exposed Veterans With PTSD.


The researchers assessed whether the synchrony between brain regions, analysed using electroencephalography (EEG) signals recorded during sleep, is altered in subjects with post-traumatic stress disorder (PTSD) and whether the results are reproducible across consecutive nights and sub-populations of the study.


Seventy-eight combat-exposed veteran men with (n = 31) and without (n = 47) PTSD completed two consecutive laboratory nights of high-density EEG recordings. They computed a measure of synchrony for each EEG channel-pair across three sleep stages [rapid eye movement (REM) and non-REM stages 2 and 3] and six frequency bands.

The researchers examined the median synchrony in nine region-of-interest (ROI) pairs consisting of six bilateral brain regions (left and right frontal, central, and parietal regions) for ten frequency-band and sleep-stage combinations.

To assess reproducibility, they used the first 47 consecutive subjects (18 with PTSD) for initial discovery and the remaining 31 subjects (13 with PTSD) for replication.


In the discovery analysis, five alpha-band synchrony pairs during non-REM sleep were consistently larger in PTSD subjects compared to controls (effect sizes ranging from 0.52 to 1.44) across consecutive nights: two between the left-frontal and left-parietal ROIs, one between the left-central and left-parietal ROIs, and two across central and parietal bilateral ROIs.

These trends were preserved in the replication set.


PTSD subjects showed increased alpha-band synchrony during non-REM sleep in the left fronto-parietal, left centro-parietal, and inter-parietal brain regions.

Importantly, these trends were reproducible across consecutive nights and sub-populations. Thus, these alterations in alpha synchrony may be discriminatory of PTSD.


Laximinarayan, S., Wang, C., Ramakrishnan, S., Oyama, T., Cashmere, J.D., Germain, A. & Reifman, J. (2020) Alterations in Sleep EEG Synchrony in Combat-Exposed Veterans With PTSD. Sleep. doi: 10.1093/sleep/zsaa006. Online ahead of print.

Let There Be Light (1946)


Let There Be Light (1946) – known to the US Army as PMF 5019 – is a documentary film directed by American filmmaker John Huston.

Intended to educate the public about posttraumatic stress disorder and its treatment among returning veterans, the film’s unscripted presentation of mental disability led to Let There Be Light being suppressed by the US government; it was not released until the 1980’s.

It is featured in the docuseries “Five Came Back“.

Outline (Background)

As the US Army was demobilising near the end of World War II it had the task of reintegrating returning military veterans back into peacetime society.

An obstacle veterans faced was the stigma surrounding “shell shock” or “psychoneurosis”, the old terms for posttraumatic stress disorder.

To convince the public, and especially employers, that veterans being treated for battle-induced mental instability were completely normal after psychiatric treatment, on 25 June 1945, the Army Signal Corps tasked Major John Huston with producing the documentary The Returning Psychoneurotics.

Huston visited multiple Army hospitals on the East and West Coasts before deciding upon Mason General Hospital on Brentwood, Long Island. The reasons being that Mason General was the biggest mental health facility on the East Coast, the hospital was located near the Army motion picture production center at Astoria Studio in Queens, New York, and the doctors were very open and receptive to the filming and any psychiatric questions he had.

The new title that Huston gave the film, Let There Be Light, was a reference to Genesis 1:3 of the King James Version of the Bible. This was an allusion to the documentary revealing truths that were previously concealed as too frightening or shameful for acknowledgement.

Outline (Documentary)

The film begins with an introduction, stating that 20% of wartime casualties are of a psychiatric nature.

Veterans are transported from a medical ship to Mason General Hospital to be treated for mental conditions brought about by war.

A group of seventy-five US service members – recent combat veterans suffering from various “nervous conditions” including psychoneurosis, battle neurosis, conversion disorder, amnesia, severe stammering, and anxiety states – arrive at the facility. They are brought into a room and told by an admissions officer to not be alarmed by the cameras, which will make a photographic record of their progress.

Next are scenes of interviews between a doctor and some of the patients about their problems and circumstances leading to that point. Afterwards, various treatment methods are employed to cure them.

Treatments depicted include narcosynthesis, hypnosis, group psychotherapy, music therapy, and work therapy. One soldier who had amnesia was hypnotised to remember the trauma of the Japanese bombings on Okinawa and his life before then. Another is given an intravenous injection of sodium amytal to induce a hypnotic state, curing him of his mental inability to walk.

The treatments are followed by classes (designed to reintegrate patients into civilian life) and group therapy sessions. Therapists make a point of reassuring the patients that there is nothing to be ashamed of for receiving treatment for their mental conditions, and that civilians subjected to the same stresses would develop the same conditions.

At this point the documentary shifts the tone to a sense of normalcy, with the soldiers performing regular activities and complaining about everyday problems.

The film ends with a number of the featured patients participating in a ceremony in which they are discharged, not just from the hospital, but from military service, and returned to civilian life.

Production & Filming Details

  • Narrator(s): Walter Huston.
  • Director(s): John Huston.
  • Producer(s): John Huston and US Army Pictorial Service.
  • Writer(s): John Huston and Charles Kaufman.
  • Music: Dimitri Tiomkin.
  • Cinematography: Stanley Cortez, John Doran, Lloyd Fromm, Joseph Jackman, and George Smith.
  • Editor(s): William H. Reynolds and Genre Fowler Jr.
  • Distributor(s): US Army.
  • Release Date: 1946.
  • Running Time: 58 minutes.
  • Country: US.
  • Language: English.

What is the Role of Combat Exposure & Malevolent Environments in Mental Health?

Research Paper Title

Do different types of war stressors have independent relations with mental health? Findings from the Korean Vietnam Veterans Study.


South Korea had the second largest contingent of soldiers in the Vietnam War, but little is known about their adaptation, especially in later life.

Previous work in a different sample found very high rates of post-traumatic stress disorder (PTSD; 41%) among Korean Vietnam veterans (KVVs; Kang, Kim, & Lee, 2014), compared to 19-31% for American Vietnam veterans.

The researchers explored possible reasons for this high rate of PTSD, as well as anxiety and depressive symptoms, utilising both vulnerability factors (e.g., war stressors) and protective factors (optimism, unit cohesion, and homecoming experiences).


The sample included 367 male KVVs surveyed by mail (M age = 72, SD = 2.66).

Using hierarchical regressions controlling for demographics, the researchers examined the relative contributions of different types of war stressors and then the protective factors.


Combat exposure was significantly associated with the three types of negative psychological symptoms, but their associations became non-significant when “subjective” war stressors (malevolent environments, perceived threat, and moral injury) were added.

In the final models, malevolent environments were the strongest predictor for all three outcomes.

In addition, moral injury was independently associated with PTSD symptoms, while perceived threat was marginally associated with depressive and anxiety symptoms.

Among psychosocial factors, only optimism was negatively associated with the mental health outcomes.


KVVs had very high rates of combat exposure, but malevolent environments played a more important role in their mental health in later life.

These findings suggest the importance of considering adverse environmental factors in understanding PTSD in future studies.


Lee, H., Aldwin, C.M. & Kang, S. (2020) Do different types of war stressors have independent relations with mental health? Findings from the Korean Vietnam Veterans Study. Psychological Trauma: Theory, Research, Practice, and Policy. doi: 10.1037/tra0000557. [Epub ahead of print].

Is There a Link between Elevated Spindle Oscillatory Frequency in PTSD & Sleep Continuity?

Research Paper Title

Increased Oscillatory Frequency of Sleep Spindles in Combat-Exposed Veteran Men with Post-Traumatic Stress Disorder.


Sleep disturbances are core symptoms of post-traumatic stress disorder (PTSD), but reliable sleep markers of PTSD have yet to be identified.

Sleep spindles are important brain waves associated with sleep protection and sleep-dependent memory consolidation.

The present study tested whether sleep spindles are altered in individuals with PTSD and whether the findings are reproducible across nights and sub-samples of the study.


Seventy-eight combat-exposed veteran men with (n = 31) and without (n = 47) PTSD completed two consecutive nights of high-density EEG recordings in a laboratory.

The researchers identified slow (10-13 Hz) and fast (13-16 Hz) sleep spindles during N2 and N3 sleep stages and performed topographical analyses of spindle parameters (amplitude, duration, oscillatory frequency, and density) on both nights.

To assess reproducibility, we used the first 47 consecutive participants (18 with PTSD) for initial discovery and the remaining 31 participants (13 with PTSD) for replication assessment.


In the discovery analysis, compared to non-PTSD participants, PTSD participants exhibited:

  1. Higher slow-spindle oscillatory frequency over the antero-frontal regions on both nights; and
  2. Higher fast-spindle oscillatory frequency over the centro-parietal regions on the second night.

The first finding was preserved in the replication analysis.

The researchers found no significant group differences in the amplitude, duration, or density of slow or fast spindles.


The elevated spindle oscillatory frequency in PTSD may indicate a deficient sensory-gating mechanism responsible for preserving sleep continuity.

The findings, if independently validated, may assist in the development of sleep-focused PTSD diagnostics and interventions.


Wang, C., Laxminarayan, S., Ramakrishnan, S., Dovzhenok, A., Cashmere, J.D., Germain, A. & Reifman, J. (2020) Increased Oscillatory Frequency of Sleep Spindles in Combat-Exposed Veteran Men with Post-Traumatic Stress Disorder. Sleep. pii: zsaa064. doi: 10.1093/sleep/zsaa064. [Epub ahead of print].