scholarly journals Intrinsic sensory disinhibition contributes to intrusive re-experiencing in combat veterans

2019 ◽  
Author(s):  
Kevin J. Clancy ◽  
Alejandro Albizu ◽  
Norman B. Schmidt ◽  
Wen Li

ABSTRACTIntrusive re-experiencing of traumatic events is a hallmark symptom of posttraumatic stress disorder (PTSD). In contrast to abstract, verbal intrusions in other affective disorders, intrusive re-experiencing in PTSD is characterized by vivid sensory details as “flashbacks”. While prevailing PTSD models largely focus on dysregulated emotional processes, we hypothesize that deficient sensory inhibition in PTSD could drive overactivation of sensory representations of trauma memories, precipitating sensory-rich intrusions of trauma. In 86 combat veterans, we examined resting-state alpha (8-12 Hz) oscillatory activity (in both power and posterior→frontal connectivity), given its key role in sensory cortical inhibition, in association with intrusive re-experiencing symptoms. A subset (N = 35) of veterans further participated in an odor task (including both combat and non-combat odors) to assess olfactory trauma memory and emotional response. We observed a strong association between intrusive re-experiencing symptoms and attenuated resting-state posterior→frontal alpha connectivity, which were both correlated with olfactory trauma memory (but not emotional response). Importantly, olfactory trauma memory was further identified as a full mediator of the relationship between alpha connectivity and intrusive re-experiencing in these veterans, suggesting that deficits in intrinsic sensory inhibition can contribute to intrusive re-experiencing of trauma via heightened trauma memory. Therefore, by permitting unfiltered sensory cues to enter information processing and spontaneously activating sensory representations of trauma, impaired sensory inhibition can constitute a sensory mechanism of intrusive re-experiencing in PTSD.HIGHLIGHTSAlpha oscillations (indexing sensory inhibition) measured in 86 combat veteransRe-experiencing symptom severity was associated with attenuated alpha connectivityTrauma memory for, not emotional response to, odors mediated this relationshipTrauma memories may arise via disinhibited activation of sensory representationsSensory systems may be novel target for intrusive re-experiencing symptom treatment

2019 ◽  
Author(s):  
Marie-Pierre Deiber ◽  
Roland Hasler ◽  
Julien Colin ◽  
Alexandre Dayer ◽  
Jean-Michel Aubry ◽  
...  

AbstractAbnormal patterns of electrical oscillatory activity have been repeatedly described in adult ADHD. In particular, the alpha rhythm (8-12 Hz), known to be modulated during attention, has previously been considered as candidate biomarker for ADHD. In the present study, we asked adult ADHD patients to self-regulate their own alpha rhythm using neurofeedback (NFB), in order to examine the modulation of alpha oscillations on attentional performance and brain plasticity. Twenty-five adult ADHD patients and 22 healthy controls underwent a 64-channel EEG-recording at resting-state and during a Go/NoGo task, before and after a 30 min-NFB session designed to reduce (desynchronize) the power of the alpha rhythm. Alpha power was compared across conditions and groups, and the effects of NFB were statistically assessed by comparing behavioral and EEG measures pre-to-post NFB. Firstly, we found that relative alpha power was attenuated in our ADHD cohort compared to control subjects at baseline and across experimental conditions, suggesting a signature of cortical hyper-activation. Both groups demonstrated a significant and targeted reduction of alpha power during NFB. Interestingly, we observed a post-NFB increase in resting-state alpha (i.e. rebound) in the ADHD group, which restored alpha power towards levels of the normal population. Importantly, the degree of post-NFB alpha normalisation during the Go/NoGo task correlated with individual improvements in motor inhibition (i.e. reduced commission errors and slower reaction times in NoGo trials) only in the ADHD group. Overall, our findings offer novel supporting evidence implicating alpha oscillations in inhibitory control, as well as their potential role in the homeostatic regulation of cortical excitatory/inhibitory balance.HighlightsResting alpha power is reduced in adult ADHD suggesting cortical hyper-activationAdult ADHD patients successfully reduce alpha power during neurofeedbackA post-neurofeedback rebound normalizes alpha power in adult ADHDAlpha power rebound correlates with improvement of inhibitory control in adult ADHD


2019 ◽  
Author(s):  
Thomas Houweling ◽  
Robert Becker ◽  
Alexis Hervais-Adelman

AbstractThe role of neuronal oscillations in the processing of speech has recently come to prominence. Since resting-state (RS) brain activity has been shown to predict both task-related brain activation and behavioural performance, we set out to establish whether inter-individual differences in spectrally-resolved RS-MEG power are associated with variations in words-in-noise recognition in a sample of 88 participants made available by the Human Connectome Project. Positive associations with resilience to noise were observed with power in the range 21 and 29Hz in a number of areas along the left temporal gyrus and temporo-parietal association areas peaking in left posterior superior temporal gyrus (pSTG). Significant associations were also found in the right posterior superior temporal gyrus in the frequency range 30 to 40Hz. We propose that individual differences in words-in-noise performance are related to baseline excitability levels of the neural substrates of phonological processing.HighlightsPower of resting MEG activity predicts Words-In-Noise recognition performanceSignificant associations in higher beta and lower gamma frequency bandStrongest in left-lateralised perisylvian cluster peaking in posterior STGEffects are spectrally and spatially consistent with phoneme-level processing


2019 ◽  
Author(s):  
Robert Becker ◽  
Alexis Hervais-Adelman

AbstractThe resting brain exhibits spontaneous patterns of activity that reflect features of the underlying neural substrate. Examination of inter-areal coupling of resting state oscillatory activity has revealed that the brain’s resting activity is composed of functional networks, whose topographies differ depending upon oscillatory frequency, suggesting a role for carrier frequency as a means of creating multiplexed, or functionally segregated, communication channels between brain areas. Using canonical correlation analysis, we examined spectrally resolved resting-state connectivity patterns derived from MEG recordings to determine the relationship between connectivity intrinsic to different frequency channels and a battery of over a hundred behavioural and demographic indicators, in a group of 89 young healthy participants. We demonstrate that each of the classical frequency bands in the range 1-40Hz (delta, theta, alpha, beta and gamma) delineates a subnetwork that is behaviourally relevant, spatially distinct, and whose expression is either negatively or positively predictive of individual traits, with the strongest link in the alpha band being negative and networks oscillating at different frequencies, such as theta, beta and gamma carrying positive function.


2015 ◽  
Vol 29 (1) ◽  
pp. 26-32 ◽  
Author(s):  
Ching-Wen Huang ◽  
Chung-Ju Huang ◽  
Chiao-Ling Hung ◽  
Chia-Hao Shih ◽  
Tsung-Min Hung

Children with attention deficit hyperactivity disorder (ADHD) are characterized by a deviant pattern of brain oscillations during resting state, particularly elevated theta power and increased theta/alpha and theta/beta ratios that are related to cognitive functioning. Physical fitness has been found beneficial to cognitive performance in a wide age population. The purpose of the present study was to investigate the relationship between physical fitness and resting-state electroencephalographic (EEG) oscillations in children with ADHD. EEG was recorded during eyes-open resting for 28 children (23 boys and 5 girls, 8.66 ± 1.10 years) with ADHD, and a battery of physical fitness assessments including flexibility, muscular endurance, power, and agility tests were administered. The results indicated that ADHD children with higher power fitness exhibited a smaller theta/alpha ratio than those with lower power fitness. These findings suggest that power fitness may be associated with improved attentional self-control in children with ADHD.


2010 ◽  
Vol 15 (2) ◽  
pp. 142-151 ◽  
Author(s):  
Wondimu Ahmed ◽  
Greetje van der Werf ◽  
Alexander Minnaert

In this article, we report on a multimethod qualitative study designed to explore the emotional experiences of students in the classroom setting. The purpose of the study was threefold: (1) to explore the correspondence among nonverbal expressions, subjective feelings, and physiological reactivity (heart rate changes) of students’ emotions in the classroom; (2) to examine the relationship between students’ emotions and their competence and value appraisals; and (3) to determine whether task difficulty matters in emotional experiences. We used multiple methods (nonverbal coding scheme, video stimulated recall interview, and heart rate monitoring) to acquire data on emotional experiences of six grade 7 students. Concurrent correspondence analyses of the emotional indices revealed that coherence between emotional response systems, although apparent, is not conclusive. The relationship between appraisals and emotions was evident, but the effect of task difficulty appears to be minimal.


2021 ◽  
Vol 10 (3) ◽  
pp. 448
Author(s):  
Federica Piani ◽  
Arrigo F. G. Cicero ◽  
Claudio Borghi

The relationship between serum uric acid (SUA) and hypertension has been a subject of increasing interest since the 1870 discovery by Frederick Akbar Mahomed. Several epidemiological studies have shown a strong association between high SUA levels and the presence or the development of hypertension. Genetic analyses have found that xanthine oxidoreductase (XOR) genetic polymorphisms are associated with hypertension. However, genetic studies on urate transporters and Mendelian randomization studies failed to demonstrate a causal relationship between SUA and hypertension. Results from clinical trials on the role of urate-lowering therapy in the management of patients with hypertension are not uniform. Our study sought to analyze the prognostic and therapeutic role of SUA in the hypertensive disease, from uric acid (UA) biology to clinical trials on urate-lowering therapies.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jelena Trajkovic ◽  
Francesco Di Gregorio ◽  
Francesca Ferri ◽  
Chiara Marzi ◽  
Stefano Diciotti ◽  
...  

AbstractSchizophrenia is among the most debilitating neuropsychiatric disorders. However, clear neurophysiological markers that would identify at-risk individuals represent still an unknown. The aim of this study was to investigate possible alterations in the resting alpha oscillatory activity in normal population high on schizotypy trait, a physiological condition known to be severely altered in patients with schizophrenia. Direct comparison of resting-state EEG oscillatory activity between Low and High Schizotypy Group (LSG and HSG) has revealed a clear right hemisphere alteration in alpha activity of the HSG. Specifically, HSG shows a significant slowing down of right hemisphere posterior alpha frequency and an altered distribution of its amplitude, with a tendency towards a reduction in the right hemisphere in comparison to LSG. Furthermore, altered and reduced connectivity in the right fronto-parietal network within the alpha range was found in the HSG. Crucially, a trained pattern classifier based on these indices of alpha activity was able to successfully differentiate HSG from LSG on tested participants further confirming the specific importance of right hemispheric alpha activity and intrahemispheric functional connectivity. By combining alpha activity and connectivity measures with a machine learning predictive model optimized in a nested stratified cross-validation loop, current research offers a promising clinical tool able to identify individuals at-risk of developing psychosis (i.e., high schizotypy individuals).


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jelena Trajkovic ◽  
Francesco Di Gregorio ◽  
Francesca Ferri ◽  
Chiara Marzi ◽  
Stefano Diciotti ◽  
...  

AbstractAn amendment to this paper has been published and can be accessed via a link at the top of the paper.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Stephanie Langella ◽  
◽  
Muhammad Usman Sadiq ◽  
Peter J. Mucha ◽  
Kelly S. Giovanello ◽  
...  

AbstractWith an increasing prevalence of mild cognitive impairment (MCI) and Alzheimer’s disease (AD) in response to an aging population, it is critical to identify and understand neuroprotective mechanisms against cognitive decline. One potential mechanism is redundancy: the existence of duplicate elements within a system that provide alternative functionality in case of failure. As the hippocampus is one of the earliest sites affected by AD pathology, we hypothesized that functional hippocampal redundancy is protective against cognitive decline. We compared hippocampal functional redundancy derived from resting-state functional MRI networks in cognitively normal older adults, with individuals with early and late MCI, as well as the relationship between redundancy and cognition. Posterior hippocampal redundancy was reduced between cognitively normal and MCI groups, plateauing across early and late MCI. Higher hippocampal redundancy was related to better memory performance only for cognitively normal individuals. Critically, functional hippocampal redundancy did not come at the expense of network efficiency. Our results provide support that hippocampal redundancy protects against cognitive decline in aging.


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