Neural oscillations while remembering traumatic memories in PTSD

AbstractBackgroundIn posttraumatic stress disorder (PTSD), the traumatic event is often re-experienced through vivid sensory fragments of the traumatic experience. Though the sensory phenomenology of traumatic memories is well established, neural indications for this qualitative experience are lacking. The current study aimed at monitoring the oscillatory brain activity of PTSD patients during directed and imaginal exposure to the traumatic memory using magnetoencephalography (MEG), in a paradigm resembling exposure therapy.MethodsBrain activity of healthy trauma-exposed controls and PTSD participants was measured with MEG as they listened to individualized trauma narratives as well as to a neutral narrative and as they imagined the narrative in detail. Source localization analysis on varied frequency bands was conducted in order to map neural generators of altered oscillatory activity.ResultsPTSD patients exhibited increased power of high-frequency bands over visual areas and increased delta and theta power over auditory areas in response to trauma recollection compared to neutral recollection, while controls did not show such differential activation. PTSD participants also showed abnormal modulation of lower frequencies in the medial prefrontal cortex.ConclusionsElicitation of traumatic memories results in a distinct neural pattern in PTSD patients compared to healthy trauma-exposed individuals. Investigating the oscillatory neural dynamics of PTSD patients can help us better understand the processes underlying trauma re-experiencing.

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Physical exercise increases overall brain oscillatory activity but does not influence inhibitory control in young adults

10.1101/268995 ◽

2018 ◽

Author(s):

Luis F. Ciria ◽

Pandelis Perakakis ◽

Antonio Luque-Casado ◽

Daniel Sanabria

Keyword(s):

Physical Exercise ◽

Inhibitory Control ◽

Frequency Band ◽

Brain Function ◽

Acute Exercise ◽

Brain Activity ◽

Oscillatory Activity ◽

Power Increase ◽

Oscillatory Brain Activity ◽

Exercise Induced

AbstractExtant evidence suggests that acute exercise triggers a tonic power increase in the alpha frequency band at frontal locations, which has been linked to benefits in cognitive function. However, recent literature has questioned such a selective effect on a particular frequency band, indicating a rather overall power increase across the entire frequency spectrum. Moreover, the nature of task-evoked oscillatory brain activity associated to inhibitory control after exercising, and the duration of the exercise effect, are not yet clear. Here, we investigate for the first time steady state oscillatory brain activity during and following an acute bout of aerobic exercise at two different exercise intensities (moderate-to-high and light), by means of a data-driven cluster-based approach to describe the spatio-temporal distribution of exercise-induced effects on brain function without prior assumptions on any frequency range or site of interest. We also assess the transient oscillatory brain activity elicited by stimulus presentation, as well as behavioural performance, in two inhibitory control (flanker) tasks, one performed after a short delay following the physical exercise and another completed after a rest period of 15’ post-exercise to explore the time course of exercise-induced changes on brain function and cognitive performance. The results show that oscillatory brain activity increases during exercise compared to the resting state, and that this increase is higher during the moderate-to-high intensity exercise with respect to the light intensity exercise. In addition, our results show that the global pattern of increased oscillatory brain activity is not specific to any concrete surface localization in slow frequencies, while in faster frequencies this effect is located in parieto-occipital sites. Notably, the exercise-induced increase in oscillatory brain activity disappears immediately after the end of the exercise bout. Neither transient (event-related) oscillatory activity, nor behavioral performance during the flanker tasks following exercise showed significant between-intensity differences. The present findings help elucidate the effect of physical exercise on oscillatory brain activity and challenge previous research suggesting improved inhibitory control following moderate-to-high acute exercise.

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The separation of auditory experience and the temporal structure of MEG recorded brain activity

10.1101/189480 ◽

2017 ◽

Author(s):

Chris Allen

Keyword(s):

High Frequency ◽

Temporal Dynamics ◽

Brain Activity ◽

Temporal Structure ◽

Oscillatory Activity ◽

Auditory Stimuli ◽

Brain Oscillations ◽

Successful Separation ◽

Auditory Experience ◽

Oscillatory Brain Activity

AbstractDo brain oscillations limit the temporal dynamics of experience? This pre-registered study used the separation of auditory stimuli to track perceptual experience and related this to oscillatory activity using magnetoencephalography. The rates at which auditory stimuli could be individuated matched the rates of oscillatory brain activity. Stimuli also entrained brain activity at the frequencies at which they were presented and a progression of high frequency gamma band events appeared to predict successful separation. These findings support a generalised function for brain oscillations, across frequency bands, in the alignment of activity to delineate representations.

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Oscillations in the central brain ofDrosophilaare phase locked to attended visual features

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2010749117 ◽

2020 ◽

Vol 117 (47) ◽

pp. 29925-29936

Author(s):

Martyna J. Grabowska ◽

Rhiannon Jeans ◽

James Steeves ◽

Bruno van Swinderen

Keyword(s):

Brain Activity ◽

Visual Navigation ◽

Central Complex ◽

Oscillatory Activity ◽

Visual Features ◽

Attention Tasks ◽

Temporal Features ◽

Object Based ◽

Oscillatory Brain Activity ◽

Beta Frequency

Object-based attention describes the brain’s capacity to prioritize one set of stimuli while ignoring others. Human research suggests that the binding of diverse stimuli into one attended percept requires phase-locked oscillatory activity in the brain. Even insects display oscillatory brain activity during visual attention tasks, but it is unclear if neural oscillations in insects are selectively correlated to different features of attended objects. We addressed this question by recording local field potentials in theDrosophilacentral complex, a brain structure involved in visual navigation and decision making. We found that attention selectively increased the neural gain of visual features associated with attended objects and that attention could be redirected to unattended objects by activation of a reward circuit. Attention was associated with increased beta (20- to 30-Hz) oscillations that selectively locked onto temporal features of the attended visual objects. Our results suggest a conserved function for the beta frequency range in regulating selective attention to salient visual features.

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EEG correlates of working memory performance in females

10.1101/098301 ◽

2017 ◽

Author(s):

Yuri G. Pavlov ◽

Boris Kotchoubey

Keyword(s):

Working Memory ◽

Individual Differences ◽

High Performance ◽

Brain Activity ◽

Memory Performance ◽

Two Dimensions ◽

Oscillatory Activity ◽

Theta Power ◽

Low Performance ◽

Oscillatory Brain Activity

AbstractBackgroundThe study investigates oscillatory brain activity during working memory (WM) tasks. The tasks employed varied in two dimensions. First, they differed in complexity from average to highly demanding. Second, we used two types of tasks, which required either only retention of stimulus set or retention and manipulation of the content. We expected to reveal EEG correlates of temporary storage and central executive components of WM and to assess their contribution to individual differences.ResultsGenerally, as compared with the retention condition, manipulation of stimuli in WM was associated with distributed suppression of alpha1 activity and with the increase of the midline theta activity. Load and task dependent decrement of beta1 power was found during task performance. Beta2 power increased with the increasing WM load and did not significantly depend on the type of the task.At the level of individual differences, we found that the high performance (HP) group was characterized by higher alpha rhythm power. The HP group demonstrated task-related increment of theta power in the left anterior area and a gradual increase of theta power at midline area. In contrast, the low performance (LP) group exhibited a drop of theta power in the most challenging condition. HP group was also characterized by stronger desynchronization of beta1 rhythm over the left posterior area in the manipulation condition. In this condition, beta2 power increased in the HP group over anterior areas, but in the LP group over posterior areas.ConclusionsWM performance is accompanied by changes in EEG in a broad frequency range from theta to higher beta bands. The most pronounced differences in oscillatory activity between individuals with high and low WM performance can be observed in the most challenging WM task.

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The Value of Hypnosis in the Resolution of Dissociation: Clinical Lessons from World War I on the Integration of Traumatic Memories

QUADERNI DI PSICOTERAPIA COGNITIVA ◽

10.3280/qpc44-2019oa8148 ◽

2019 ◽

pp. 11-49 ◽

Cited By ~ 1

Author(s):

Onno van der Hart

Keyword(s):

World War I ◽

Traumatic Experience ◽

Traumatic Memory ◽

World War ◽

Traumatic Memories ◽

Previous Trauma ◽

History Of ◽

War Experiences ◽

Simple Phase

Some World War I clinicians related the symptoms of traumatized servicemen to an underlying dissociation of their personality, consisting of two prototypical conditions: one involving functioning in daily life (inspired by Myers, whose work is also discussed in this article, and which will be labeled apparently normal part of the personality [ANP]) and one involving fixation in the traumatic experience and related attempts at defense (emotional part of the personality [EP]). These authors described two dissociative patterns. As illustrated in this article, one pattern consisted in the presentation of a dominant ANP suffering from constant or frequent intrusions from EP. The other pattern consisted in repeated complete alternations between ANP and EP. Instead of the use of purely symptom-oriented approaches, for the dissociative symptoms to be really resolved, an integration of traumatic memory in the personality, that is, between EP and ANP had to take place. These clinicians used hypnosis to access the traumatic memory and EP and to foster such integration; they agreed on the importance of the quality of the therapeutic relationship in this regard. However, they differed in opinion and practice as to the need to assists patients in their expression of traumatic emotions during this process. When the trauma was related merely to war experiences, such therapeutic processes took place within a simple phase-oriented treatment model, while in the presence of a history of previous trauma and related dissociation of the personality, this model had more complex applications. This is similar to modern treatment approaches of the sequelae - such as a complex dissociative disorder - of chronic (childhood) traumatization.

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Memory of the Traumatic Event as a Risk Factor for the Development of PTSD: Lessons from the Study of Traumatic Brain Injury

CNS Spectrums ◽

10.1017/s1092852900013651 ◽

2006 ◽

Vol 11 (8) ◽

pp. 603-607 ◽

Cited By ~ 9

Author(s):

Sharon Gil ◽

Yael Caspi ◽

Irit Ben-Ari ◽

Ehud Klein

Keyword(s):

Traumatic Brain Injury ◽

Brain Injury ◽

Stress Disorder ◽

Traumatic Event ◽

Traumatic Memory ◽

Ethical Considerations ◽

Traumatic Memories ◽

Naturally Occurring ◽

The Relationship ◽

With Memory

ABSTRACTTraumatic memories, and the mechanisms by which they operate, continue to occupy a central role in the scientific investigation of risk factors for the development of posttraumatic stress disorder (PTSD). However, empirically based studies are constrained by practical and ethical considerations and are limited to naturalistic models. Consequently, the paradigms most appropriate for the exploration of the relationship between traumatic memories and PTSD have been identified in conditions involving traumatic events where memories may be compromised. Indeed, traumatic brain injury, a condition that is commonly associated with memory impairment, has often been utilized as a naturally occurring model for the study of traumatic memory and its contribution to the development of PTSD. This article presents a critical review of these research efforts and discusses their theoretical and clinical implications.

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EEG Oscillatory Phase-Dependent Markers of Corticospinal Excitability in the Resting Brain

BioMed Research International ◽

10.1155/2014/936096 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 33

Author(s):

Barbara Berger ◽

Tamas Minarik ◽

Gianpiero Liuzzi ◽

Friedhelm C. Hummel ◽

Paul Sauseng

Keyword(s):

Cortical Excitability ◽

Brain Activity ◽

Motor Evoked Potential ◽

Corticospinal Excitability ◽

Neuronal Firing ◽

Oscillatory Activity ◽

Brain Oscillations ◽

Frequency Bands ◽

Instantaneous Phase ◽

Brain States

Functional meaning of oscillatory brain activity in various frequency bands in the human electroencephalogram (EEG) is increasingly researched. While most research focuses on event-related changes of brain activity in response to external events there is also increasing interest in internal brain states influencing information processing. Several studies suggest amplitude changes of EEG oscillatory activity selectively influencing cortical excitability, and more recently it was shown that phase of EEG activity (instantaneous phase) conveys additional meaning. Here we review this field with many conflicting findings and further investigate whether corticospinal excitability in the resting brain is dependent on a specific spontaneously occurring brain state reflected by amplitude and instantaneous phase of EEG oscillations. We applied single pulse transcranial magnetic stimulation (TMS) over the left sensorimotor cortex, while simultaneously recording ongoing oscillatory activity with EEG. Results indicate that brain oscillations reflect rapid, spontaneous fluctuations of cortical excitability. Instantaneous phase but not amplitude of oscillations at various frequency bands at stimulation site at the time of TMS-pulse is indicative for brain states associated with different levels of excitability (defined by size of the elicited motor evoked potential). These results are further evidence that ongoing brain oscillations directly influence neural excitability which puts further emphasis on their role in orchestrating neuronal firing in the brain.

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An Efficient System for Eye Movement Desensitization and Reprocessing (EMDR) Therapy: A Pilot Study

Healthcare ◽

10.3390/healthcare10010133 ◽

2022 ◽

Vol 10 (1) ◽

pp. 133

Author(s):

Nicolae Goga ◽

Costin-Anton Boiangiu ◽

Andrei Vasilateanu ◽

Alexandru-Filip Popovici ◽

Marius-Valentin Drăgoi ◽

...

Keyword(s):

Eye Movement ◽

Traumatic Event ◽

Traumatic Memory ◽

Post Traumatic Stress ◽

Efficient System ◽

Traumatic Memories ◽

The Past ◽

Post Traumatic ◽

Disorder Treatment ◽

Emdr Therapy

In this paper, we describe an actuator-based EMDR (eye movement desensitization and reprocessing) virtual assistant system that can be used for the treatment of participants with traumatic memories. EMDR is a psychological therapy designed to treat emotional distress caused by a traumatic event from the past, most frequently in post-traumatic stress disorder treatment. We implemented a system based on video, tactile, and audio actuators which includes an artificial intelligence chatbot, making the system capable of acting autonomously. We tested the system on a sample of 31 participants. Our results showed the efficiency of the EMDR virtual assistant system in reducing anxiety, distress, and negative cognitions and emotions associated with the traumatic memory. There are no such systems reported in the existing literature. Through the present research, we fill this gap by describing a system that can be used by patients with traumatic memories.

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Unmixing Oscillatory Brain Activity by EEG Source Localization and Empirical Mode Decomposition

Computational Intelligence and Neuroscience ◽

10.1155/2019/5618303 ◽

2019 ◽

Vol 2019 ◽

pp. 1-15 ◽

Cited By ~ 3

Author(s):

Sofie Therese Hansen ◽

Apit Hemakom ◽

Mads Gylling Safeldt ◽

Lærke Karen Krohne ◽

Kristoffer Hougaard Madsen ◽

...

Keyword(s):

Empirical Mode Decomposition ◽

Source Localization ◽

Primary Motor Cortex ◽

Brain Activity ◽

Motor Evoked Potential ◽

Region Of Interest ◽

Oscillatory Activity ◽

Electrical Brain Activity ◽

Mode Decomposition ◽

Oscillatory Brain Activity

Neuronal activity is composed of synchronous and asynchronous oscillatory activity at different frequencies. The neuronal oscillations occur at time scales well matched to the temporal resolution of electroencephalography (EEG); however, to derive meaning from the electrical brain activity as measured from the scalp, it is useful to decompose the EEG signal in space and time. In this study, we elaborate on the investigations into source-based signal decomposition of EEG. Using source localization, the electrical brain signal is spatially unmixed and the neuronal dynamics from a region of interest are analyzed using empirical mode decomposition (EMD), a technique aimed at detecting periodic signals. We demonstrate, first in simulations, that the EMD is more accurate when applied to the spatially unmixed signal compared to the scalp-level signal. Furthermore, on EEG data recorded simultaneously with transcranial magnetic stimulation (TMS) over the hand area of the primary motor cortex, we observe a link between the peak to peak amplitude of the motor-evoked potential (MEP) and the phase of the decomposed localized electrical activity before TMS onset. The results thus encourage combination of source localization and EMD in the pursuit of further insight into the mechanisms of the brain with respect to the phase and frequency of the electrical oscillations and their cortical origin.

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RE-EXPERIENCING AS A SYMPTOM OF POSTTRAUMATIC STRESS DISORDER

PSYCHOLOGICAL JOURNAL ◽

10.31108/1.2019.5.7.14 ◽

2019 ◽

Vol 5 (9) ◽

pp. 208-221

Author(s):

Spartak Subbota ◽

Keyword(s):

Stress Disorder ◽

Traumatic Event ◽

Emotional Reaction ◽

Traumatic Experience ◽

Post Traumatic Stress ◽

Traumatic Memories ◽

Related Information ◽

Extraction Pattern ◽

Psychological Mechanism ◽

Post Traumatic

The article shows that intrusive reexperiencing is one of key symptoms of post-traumatic stress disorder (PTSD) that can be manifestedin various forms, for example, intrusive ideas and images, nightmares, flashbacks, stress, physiological reactions and so on. Researchers mostly agree that symptom of re-experiencing is related to methods of coding traumatic memories, storing them in one’s memory and extraction. Pattern of selective identification of elements related to the traumatic event and strong emotional reaction on these triggers looks like a normal adaptive reaction soon after the trauma, as a person needs to re-estimate safety of his/her own environment. Many people recover relatively quickly, working with the trauma alone or with the help of a psychotherapist, in particular through the processes of establishment of autobiographic memories about the event of the trauma as well as its proximal context, both temporal and situational. These people further notice that triggers work as signals of false alarm, and that actually they do not signal about any immediate danger. However for some patients reexperiencing can still remain: if a person can’t place traumatic memories within corresponding context of time and place (for example, when working with memories alone or at least without professional help) with periodical memory updates using trauma-related information, then intrusive re-experiencing works as a trigger reaction remains quite working psychological mechanism. It is proven that it is important to take into account features of both conscious and involuntary memories when describingpost-traumatic memories among PTSD patients. It is shown that key elements of traumatic experience are memorized best of all, and details are remembered worse and less detailed. Although such tendency is consistentwith posttraumatic narratives from patients with PTSD, it however lacks to explain maintenance of symptom of repeated experiencing; warning signals hypothesis, in our opinion, shows the best explanatory potential in this case. Moreover, problems with the conscious remembering of the traumatic experiencing also promote attention to problems with adequate estimations of trauma in general, and consequently are important for professional understanding of abnormal psychology of PTSD.

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