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 brain's 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.

Voluntary control of auditory hallucinations: phenomenology to therapeutic implications

“…Social expectations themselves are learned from one's past social experiences; thus, the use of social expectations to inform precision of perceptual priors may explain some of the known relationships between trauma exposure, locus of control, agency, and ability to control one's hallucinations 109 . Indeed, past trauma has been shown to affect processes related to detection of basic auditory stimulus features 110 . These processes also change with affective state 111 .…”

Interpretable Principal Components Analysis for Multilevel Multivariate Functional Data, with Application to EEG Experiments

“…More specifically, recalling that the estimated second subject-level component is a measures of whole-brain theta power, if a person has a history of trauma, the higher his/her theta power, the lower their expected dissociation level. Theta power is associated with memory and emotional control and has been shown to be elevated in participants with a history of post traumatic stress disorder (Bangel et al, 2017). This result may suggest that during instructed rumination, if a person has a history of trauma, not engaging memory related circuitry, perhaps failing to reinvoke trauma recollections, even when a person wants to, may involve dissociation.…”

Multifeature Mismatch Negativity in Patients With Posttraumatic Stress Disorder

“…The outcome of our study differs from the findings of similar previously published studies. In particular, larger MMNs have been linked with PTSD in previous studies 8-10 that all used standard oddball protocols. In contrast, the only other study that employed a multifeature protocol 11 found reduced MMN amplitudes in PTSD, in particular when the deviants differed from standard sounds in the dimensions gap and duration.…”

“…Significantly larger MMNs (again elicited by frequency deviants) were also found in individuals that developed PTSD after experiencing a destructive earthquake compared with a control group that did not develop PTSD after the same event. 9 A more recent study by Bangel et al 10 compared trauma-exposed males with PTSD with a trauma-exposed control group without PTSD and found enhanced MMNs using deviants that differed from standards in both frequency and duration. These findings have been interpreted as increased sensitivity to stimulus changes in PTSD as a result of hypervigilance and hyperarousal.…”