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bioRxiv · 10.1101/186460

Aberrant brain response after auditory deviance in PTSD compared to trauma controls: An EEG study.

Abstract

Part of the symptomatology of post-traumatic stress disorder (PTSD) are alterations in arousal and reactivity which could be related to a maladaptive increase in the automated sensory change detection system of the brain. In the current EEG study we investigated whether the brains response to a simple auditory sensory change was altered in patients with PTSD relative to trauma-exposed matched controls who did not develop the disorder. Thirteen male PTSD patients and trauma-exposed controls matched for age and educational level were presented regular auditory pure tones (1000 Hz, 200 ms duration), with 11% of the tones deviating in both duration (50 ms) and frequency (1200 Hz) while watching a silent movie. Relative to the controls, patients who had developed PTSD showed enhanced mismatch negativity (MMN), increased theta power (5-7 Hz), and stronger suppression of upper alpha activity (13-15 Hz) after deviant vs. standard tones. Behaviourally, the alpha suppression in PTSD correlated with decreased spatial working memory performance suggesting it might reflect enhanced stimulus-feature representations in auditory memory. These results taken together suggest that PTSD patients and trauma-exposed controls can be distinguished by enhanced involuntary attention to changes in sensory patterns.

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BibTeXRIS

Bangel, K. A., van Buschbach, S., Smit, D. J. H., Olff, M., Mazaheri, A.. 2017-09-13. Aberrant brain response after auditory deviance in PTSD compared to trauma controls: An EEG study.. https://doi.org/10.1101/186460

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