2,379 research outputs found
On the analysis of EEG power, frequency and asymmetry in Parkinson's disease during emotion processing
Objective: While Parkinson’s disease (PD) has traditionally been described as a movement disorder, there is growing evidence of disruption in emotion information processing associated with the disease. The aim of this study was to investigate whether there are specific electroencephalographic (EEG) characteristics that discriminate PD patients and normal controls during emotion information processing.
Method: EEG recordings from 14 scalp sites were collected from 20 PD patients and 30 age-matched normal controls. Multimodal (audio-visual) stimuli were presented to evoke specific targeted emotional states such as happiness, sadness, fear, anger, surprise and disgust. Absolute and relative power, frequency and asymmetry measures derived from spectrally analyzed EEGs were subjected to repeated ANOVA measures for group comparisons as well as to discriminate function analysis to examine their utility as classification indices. In addition, subjective ratings were obtained for the used emotional stimuli.
Results: Behaviorally, PD patients showed no impairments in emotion recognition as measured by subjective ratings. Compared with normal controls, PD patients evidenced smaller overall relative delta, theta, alpha and beta power, and at bilateral anterior regions smaller absolute theta, alpha, and beta power and higher mean total spectrum frequency across different emotional states. Inter-hemispheric theta, alpha, and beta power asymmetry index differences were noted, with controls exhibiting greater right than left hemisphere activation. Whereas intra-hemispheric alpha power asymmetry reduction was exhibited in patients bilaterally at all regions. Discriminant analysis correctly classified 95.0% of the patients and controls during emotional stimuli.
Conclusion: These distributed spectral powers in different frequency bands might provide meaningful information about emotional processing in PD patients
Optimal set of EEG features for emotional state classification and trajectory visualization in Parkinson's disease
In addition to classic motor signs and symptoms, individuals with Parkinson's disease (PD) are characterized by emotional deficits. Ongoing brain activity can be recorded by electroencephalograph (EEG) to discover the links between emotional states and brain activity. This study utilized machine-learning algorithms to categorize emotional states in PD patients compared with healthy controls (HC) using EEG. Twenty non-demented PD patients and 20 healthy age-, gender-, and education level-matched controls viewed happiness, sadness, fear, anger, surprise, and disgust emotional stimuli while fourteen-channel EEG was being recorded. Multimodal stimulus (combination of audio and visual) was used to evoke the emotions. To classify the EEG-based emotional states and visualize the changes of emotional states over time, this paper compares four kinds of EEG features for emotional state classification and proposes an approach to track the trajectory of emotion changes with manifold learning. From the experimental results using our EEG data set, we found that (a) bispectrum feature is superior to other three kinds of features, namely power spectrum, wavelet packet and nonlinear dynamical analysis; (b) higher frequency bands (alpha, beta and gamma) play a more important role in emotion activities than lower frequency bands (delta and theta) in both groups and; (c) the trajectory of emotion changes can be visualized by reducing subject-independent features with manifold learning. This provides a promising way of implementing visualization of patient's emotional state in real time and leads to a practical system for noninvasive assessment of the emotional impairments associated with neurological disorders
Recommended from our members
Transcranial Focused Ultrasound to the Right Prefrontal Cortex Improves Mood and Alters Functional Connectivity in Humans
Transcranial focused ultrasound (tFUS) is an emerging method for non-invasive neuromodulation akin to transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS). tFUS offers several advantages over electromagnetic methods including high spatial resolution and the ability to reach deep brain targets. Here we describe two experiments assessing whether tFUS could modulate mood in healthy human volunteers by targeting the right inferior frontal gyrus (rIFG), an area implicated in mood and emotional regulation. In a randomized, placebo-controlled, double-blind study, participants received 30 s of 500 kHz tFUS or a placebo control. Visual Analog Mood Scales (VAMS) assessed mood four times within an hour (baseline and three times after tFUS). Participants who received tFUS reported an overall increase in Global Affect (GA), an aggregate score from the VAMS scale, indicating a positive shift in mood. Experiment 2 examined resting-state functional (FC) connectivity using functional magnetic resonance imaging (fMRI) following 2 min of 500 kHz tFUS at the rIFG. As in Experiment 1, tFUS enhanced self-reported mood states and also decreased FC in resting state networks related to emotion and mood regulation. These results suggest that tFUS can be used to modulate mood and emotional regulation networks in the prefrontal cortex
Measuring the Plasticity of Social Approach: A Randomized Controlled Trial of the Effects of the PEERS Intervention on EEG Asymmetry in Adolescents with Autism Spectrum Disorders
This study examined whether the Program for the Education and Enrichment of Relational Skills (PEERS: Social skills for teenagers with developmental and autism spectrum disorders: The PEERS treatment manual, Routledge, New York, 2010a) affected neural function, via EEG asymmetry, in a randomized controlled trial of adolescents with Autism spectrum disorders (ASD) and a group of typically developing adolescents. Adolescents with ASD in PEERS shifted from right-hemisphere gamma-band EEG asymmetry before PEERS to left-hemisphere EEG asymmetry after PEERS, versus a waitlist ASD group. Left-hemisphere EEG asymmetry was associated with more social contacts and knowledge, and fewer symptoms of autism. Adolescents with ASD in PEERS no longer differed from typically developing adolescents in left-dominant EEG asymmetry at post-test. These findings are discussed via the Modifier Model of Autism (Mundy et al. in Res Pract Persons Severe Disabl 32(2):124, 2007), with emphasis on remediating isolation/withdrawal in ASD
A systematic review of the neurophysiology of mindfulness on EEG oscillations
Mindfulness meditation has been purported as a beneficial practice for wellbeing. It would
be expected that the neurophysiology of mindfulness would reflect this impact on wellbeing.
However, investigations of the effect of mindfulness have generated mixed reports of
increases, decreases, as well as no differences in EEG oscillations in comparison with a
resting state and a variety of tasks. We have performed systematic review of EEG studies of
mindfulness meditation in order to determine any common effects and to identify factors
which may impact on the effects. Databases were reviewed from 1966 to August 2015.
Eligibility criteria included empirical quantitative analyses of mindfulness meditation practice
and EEG measurements acquired in relation to practice. A total of 56 papers met the
eligibility criteria and were included in the systematic review, consisting of a total 1,715
subjects: 1,358 healthy individuals and 357 individuals with psychiatric diagnoses. Studies
were principally examined for power outcomes in each bandwidth, in particular the power
differentials between mindfulness and the control state, as well as outcomes relating to
hemispheric asymmetry and event-related potentials. The systematic review revealed that
mindfulness was most commonly associated with enhanced alpha and theta power as
compared to an eyes closed resting state, although such outcomes were not uniformly
reported. No consistent patterns were observed with respect to beta, delta and gamma
bandwidths. In summary, mindfulness is associated with increased alpha and theta power in
both healthy individuals and in patient groups. This co-presence of elevated alpha and theta
may signify a state of relaxed alertness which is conducive to mental health
Frontal Alpha and Beta EEG Power Asymmetry and Iowa Gambling Task Performance
Frontal electroencephalographic (EEG) alpha (α) asymmetry may index the activation of lateralized affect and motivation systems in humans. Resting EEG activation was measured and its relationship to Iowa gambling task (IGT) performance was evaluated. No effects were found for α power asymmetry. However, beta (β) power asymmetry, an alternative measure of resting EEG activation, was associated with the number of risky decisions made in the early portion of the task. Additionally, IGT deck selection patterns suggest there are at least three distinct performance styles in healthy individuals. Interestingly, β power asymmetry contradicts performance predictions based on accepted frontal asymmetry affect and motivation models
EEG resting asymmetries and frequency oscillations in approach/avoidance personality traits: a systematic review
Background: Brain cortical activity in resting electroencephalogram (EEG) recordings
can be considered as measures of latent individual disposition to approach/avoidance behavior.
This systematic review aims to provide an updated overview of the relationship between resting
EEG cortical activity and approach/avoidance motivation personality traits. Methods: The review
process was conducted according to the PRISMA-Statement, using PsycArticles, MEDLINE, Scopus,
Science Citation Index, and Research Gate database. Restrictions were made by selecting EEG studies
conducted in resting idling conditions, which included approach/avoidance personality traits or
parallel measures, and an index of EEG brain activity. In the review 50 studies were selected, wherein
7120 healthy adult individuals participated. Results: The study of the relationship between resting
EEG cortical activity and approach/avoidance personality traits provides controversial and unclear
results. Therefore, the validity of resting asymmetry or frequency oscillations as a potential marker for
approach/avoidance personality traits is not supported. Conclusions: There are important contextual
and interactional factors not taken into account by researchers that could mediate or moderate
this relationship or prove it scarcely replicable. Further, it would be necessary to conduct more
sessions of EEG recordings in different seasons of the year to test the validity and the reliability of the
neurobiological measures
Mental sleep activity and disturbing dreams in the lifespan
Sleep significantly changes across the lifespan, and several studies underline its crucial role in cognitive functioning. Similarly, mental activity during sleep tends to covary with age. This review aims to analyze the characteristics of dreaming and disturbing dreams at dierent age brackets. On the one hand, dreams may be considered an expression of brain maturation and cognitive development, showing relations with memory and visuo-spatial abilities. Some investigations reveal that specific electrophysiological patterns, such as frontal theta oscillations, underlie dreams during sleep, as well as episodic memories in the waking state, both in young and older adults. On the other hand, considering the role of dreaming in emotional processing and regulation, the available literature suggests that mental sleep activity could have a beneficial role when stressful events occur at dierent age ranges. We highlight that nightmares and bad dreams might represent an attempt to cope the adverse events, and the degrees of cognitive-brain maturation could impact on these mechanisms across the lifespan. Future investigations are necessary to clarify these relations. Clinical protocols could be designed to improve cognitive functioning and emotional regulation by modifying the dream contents or the ability to recall/non-recall them
The Psychological Correlates of Asymmetric Cerebral Activation
This study examined the psychological correlates of asymmetric cerebral activation as measured by electroencephalograph (EEG) recordings. Five content areas were investigated in the context of EEG asymmetry: hierarchical visual processing, creative potential, mood, personality, and EEG asymmetry, and the effect of a mood induction procedure on cognition and EEG asymmetry. Undergraduate participants completed two experimental sessions separated by two to three weeks. Participants completed a comprehensive set of emotion, personality, and creative potential measures, a cognitive task assessing individual differences in hierarchical visual processing. and a short form of the Rorschach inkblot test. Additionally. each participant underwent either a happy or a sad mood induction procedure to examine the effects of mood on verbal and spatial fluency tasks and EEG asymmetry. EEG was measured in frontal, central. and parietal locations. The primary findings regarding the psychometrics of EEG asymmetry suggested that a large proportion of participants show relatively stable EEG asymmetry across two to three weeks. The results failed to replicate previous research suggesting a relationship between hierarchical visual analysis and mood using a Global-Local task. The results also failed to support the hypothesis that the Rorschach could be used as a measure of hierarchical visual analysis. However, Minor Detail location responses on the Rorschach correlated positively with negative affect and negatively with positive affect. Regarding creativity, the Rorschach was found to be a viable means of assessing individual differences in primary process cognition using the Regressive Imagery Dictionary (Martindale, 1975). Additionally, the results partially supported Martindale\u27s (1 999) hypothesis that creative people show greater right-hemisphere activation. No support was found for the hypothesized relationships between frontal activation asymmetry and mood or personality. Regarding the effect of mood on verbal and spatial fluency, no support was found for the hypothesis that happy moods increase verbal fluency and decrease spatial fluency or that sad moods increase spatial tluency and decrease verbal fluency. Happy and sad mood also did not have a significant effect on EEG asymmetry in the predicted directions. The results are discussed in terms of the status of recent research on EEG asymmetry and its relation to cognition, creativity, emotion and personality
Detection of emotions in Parkinson's disease using higher order spectral features from brain's electrical activity
Non-motor symptoms in Parkinson's disease (PD) involving cognition and emotion have been progressively receiving more attention in recent times. Electroencephalogram (EEG) signals, being an activity of central nervous system, can reflect the underlying true emotional state of a person. This paper presents a computational framework for classifying PD patients compared to healthy controls (HC) using emotional information from the brain's electrical activity
- …