Differentiating psychogenic nonepileptic from epileptic seizures: A mixed-methods, content analysis study.

BACKGROUND: Identification of clinical features that might distinguish psychogenic nonepileptic seizures (PNES) from epileptic seizures (ES) is of value for diagnosis, management, and understanding of both conditions. Previous studies have shown that patients' descriptions of their seizures reflect differences in content and delivery. We aimed to compare verbal descriptions of PNES and ES using a mixed-methods approach. METHODS: We analyzed data from semi-structured interviews in which patients with video-electroencephalography (EEG)-confirmed ES (n = 30) or PNES (n = 10) described their seizures. Two masked raters independently coded the transcripts for relevant psychological categories and discrepancies that were noted and resolved. Additional analyses were conducted using the Linguistic Inquiry and Word Count system. The identified phenomena were descriptively compared, and inferential analyses assessed group differences in frequencies. A logistic regression analysis examined the predictive power of the most distinctive phenomena for diagnosis. RESULTS: As compared with ES, PNES reported longer seizures, more preseizure negative emotions (e.g., fear), anxiety symptoms (e.g., arousal, hyperventilation), altered vision/olfaction, and automatic behaviors. During seizures, PNES reported more fear, altered breathing, and dissociative phenomena (depersonalization, impaired time perception). Epileptic seizures reported more self-injurious behavior. Postseizure, PNES reported more fear and weeping and ES more amnesia and aches. The predictive power when including these variables was 97.5%. None of the single predictor variables was significant. The few but consistent linguistic differences related to the use of some pronouns and references to family. CONCLUSIONS: Although no single clinical feature definitively distinguishes PNES from ES, several features may be suggestive of a PNES diagnosis, including longer duration, negative emotion (i.e., fear) throughout the events, preseizure anxiety, ictal dissociation, and postseizure weeping. Fewer reports of ictal self-injury and postseizure amnesia and aches may also indicate the possibility of PNES.

Differentiating PNES from epileptic seizures using conversational analysis on French patients: A prospective blinded study.

Psychogenic nonepileptic seizures (PNES) resemble epileptic seizures (ES) but are not caused by the occurrence of excessive cortical neuronal discharge. Previous studies in German-, English-, and Italian-speaking patients showed that patients used a different communicative style to talk about their seizures. They demonstrated that the diagnosis between PNES and ES could be predicted using qualitative assessment and a diagnostic scoring aid (DSA). The objective of our study was to evaluate the contribution of linguistic analysis in the differential diagnosis between ES and PNES in a French patient population. During an extended video-electroencephalogram (video-EEG) monitoring, 13 patients presented PNES and 19 patients with ES. Two neurologists blindly and independently analyzed the interview of each patient. Rater 1 predicted the correct diagnosis in 27 of 32 patients (84%) and Rater 2 in 28 of 32 patients (88%). Interrater reliability of qualitative analysis was satisfactory (k = 0.68, interrater agreement = 84.4%). Using a simplified DSA, Rater 1 and Rater 2 would have correctly diagnosed 88% (28/32 patients) and 91 % (29/32) of the cases, respectively. Our blinded prospective study confirms the diagnostic value of conversational analysis, performed by neurologists, to differentiate PNES from ES in French-speaking patients.

Psychosocial complications in juvenile myoclonic epilepsy.

Juvenile myoclonic epilepsy (JME) constitutes about 10% of all epilepsies. Because of executive dysfunction, people with JME may be prone to impulsivity and risk-taking behavior. Our aim was to investigate whether psychosocial issues associated with impulsivity are more prominent in people with JME than in those with other types of genetic generalized epilepsy (GGE). Patients with GGE were recruited retrospectively through the Drammen Hospital records in Buskerud County, Norway, 1999-2013. They were invited to a semi-structured interview, either at the hospital or at home. Ninety-two patients with JME and 45 with other types of GGE were interviewed. Variables were evaluated in terms of their association with JME versus other GGE diagnosis using a logistic regression model. Juvenile myoclonic epilepsy was associated with use of illicit recreational drugs and police charges, although with borderline significance (odds ratio [OR] 3.4, p = 0.087 and OR 4.2, p = 0.095); JME was also associated with being examined for attention-deficit hyperactivity disorder (ADHD) in females (OR 15.5, p = 0.015), a biological parent with challenges like addiction or violent behavior (OR 3.5, p = 0.032), and use of levetiracetam (OR 5.1, p = 0.014). After controlling for group differences, we found psychosocial complications to be associated with JME, potentially influencing the lives of the individuals and their families to a greater extent than the seizures per se. Thus, JME should be considered a disorder of the brain in a broader sense than a condition with seizures only.

Acute effects of meditation training on the waking and sleeping brain: Is it all about homeostasis?

Our recent finding of a meditation-related increase in low-frequency NREM sleep EEG oscillatory activities peaking in the theta-alpha range (4-12 Hz) was not predicted. From a consolidated body of research on sleep homeostasis, we would expect a change peaking in slow wave activity (1-4 Hz) following an intense meditation session. Here we compared these changes in sleep with the post-meditation changes in waking rest scalp power to further characterize their functional significance. High-density EEG recordings were acquired from 27 long-term meditators (LTM) on three separate days at baseline and following two 8-hr sessions of either mindfulness or compassion-and-loving-kindness meditation. Thirty-one meditation-naïve participants (MNP) were recorded at the same time points. As a common effect of meditation practice, we found increases in low and fast waking EEG oscillations for LTM only, peaking at eight and 15 Hz respectively, over prefrontal, and left centro-parietal electrodes. Paralleling our previous findings in sleep, there was no significant difference between meditation styles in LTM as well as no difference between matched sessions in MNP. Meditation-related changes in wakefulness and NREM sleep were correlated across space and frequency. A significant correlation was found in the EEG low frequencies (<12 Hz). Since the peak of coupling was observed in the theta-alpha oscillatory range, sleep homeostatic response to meditation practice is not sufficient to explain our findings. Another likely phenomenon into play is a reverberation of meditation-related processes during subsequent sleep. Future studies should ascertain the interplay between these processes in promoting the beneficial effects of meditation practice.

Disgust but not Health Anxiety Graphic Warning Labels Reduce Motivated Attention in Smokers: A Study of P300 and Late Positive Potential Responses.

Background: Graphic health warning labels (GHWLs) on tobacco products attempt to leverage avoidance-promoting emotions, such as anxiety and disgust, to encourage cessation. Prior studies have relied on self-report or attentional metrics that may not accurately illuminate GHWLs' ability to motivate change. This report evaluates the impact of disgust- and anxiety-based GHWLs on electroencephalograph (EEG) measures of motivated attention among two groups of smokers-those that report higher versus lower cigarette dependence. We hypothesized that both anxiety and disgust GHWLs would reduce appetitive attention, as indexed by lowered P300 (P3) and late positive potential (LPP) activations. Methods: Sixty-one smokers provided demographic and smoking history before completing an oddball paradigm consisting of three counterbalanced stimuli blocks. Each block (100 trials) contained a neutral, GHWL-anxiety, or GHWL-disgust frequent image and a smoking cue as the oddball image (20%). Oddball trials for each block were averaged, P3 and LPP were identified at midline electrode positions (Fz, Cz, and Pz), and mean amplitude was analyzed. Results: Separate mixed-model ANOVAs of P3 and LPP reactivity revealed disgust-focused GHWLs reduced motivated attentional processing. Conversely, the anxiety-focused GHWL appeared to increase the salience of the smoking cue (Fz only). Less-dependent smokers showed lower P3 reactivity than those with higher dependence at Fz, but greater P3 reactivity at Cz and Pz. Conclusion: These results extend prior work in demonstrating that disgust, but not anxiety-based GHWLs, may reduce EEG-assessed motivated attention to smoking cues. Disgust may thus represent a more fruitful target for public health cessation efforts. Implications: Most GHWL evaluations have focused on fear (or anxiety) elicitation rather than disgust, an emotion that may have a unique link to smoking, having evolved specifically to facilitate the avoidance of contaminants via oral incorporation. Analyses of P300 and LPP responses to GHWLs suggest that disgust-focused images interfere with the EEG-indexed attentional processing of smoking cues and do so better than health anxiety-focused messages. However, interaction effects at different electrode sites indicated that GHWLs have complex effects in more versus less-dependent smokers and that an understanding of how smoking cues and anti-smoking imagery become associated over time is needed to identify relevant targets for public health efforts.

Tolerability of a comprehensive cardiorespiratory monitoring protocol in an epilepsy monitoring unit.

BACKGROUND: Recent reports of fatal or near-fatal events in epilepsy monitoring units (EMUs) and an increasing awareness of the effects of seizures on breathing have stimulated interest in cardiorespiratory monitoring for patients undergoing video-electroencephalography (EEG) recording. Patient and provider acceptance of these extra recording devices has not previously been studied and may represent a barrier to widespread adoption. METHODS: We queried EMU subjects regarding their experiences with a monitoring protocol that included the continuous measurement of oral/nasal airflow, respiratory effort (chest and abdominal respiratory inductance plethysmography), oxygen saturation, and transcutaneous CO2. Surveys were returned by 71.4% (100/140) of eligible subjects. RESULTS: Overall, 73% of participants reported being moderately to highly satisfied with the monitoring, and 82% reported moderate to strong agreement that advance knowledge of the monitoring would not have changed their decision to proceed with the video-EEG study. Except for nasal airflow, none of the additional monitoring devices caused more discomfort than EEG electrodes. CONCLUSION: Patient acceptance of an EMU comprehensive cardiorespiratory monitoring protocol is high. The information obtained from "multimodality recording" should help clinicians and investigators understand the effect of seizures on both cardiac and respiratory physiology, may enhance safety in the EMU, and may aid in the identification of biomarkers for sudden unexpected death in epilepsy (SUDEP).

Reward-based contextual learning supported by anterior cingulate cortex.

The anterior cingulate cortex (ACC) is commonly associated with cognitive control and decision making, but its specific function is highly debated. To explore a recent theory that the ACC learns the reward values of task contexts (Holroyd & McClure in Psychological Review, 122, 54-83, 2015; Holroyd & Yeung in Trends in Cognitive Sciences, 16, 122-128, 2012), we recorded the event-related brain potentials (ERPs) from participants as they played a novel gambling task. The participants were first required to select from among three games in one "virtual casino," and subsequently they were required to select from among three different games in a different virtual casino; unbeknownst to them, the payoffs for the games were higher in one casino than in the other. Analysis of the reward positivity, an ERP component believed to reflect reward-related signals carried to the ACC by the midbrain dopamine system, revealed that the ACC is sensitive to differences in the reward values associated with both the casinos and the games inside the casinos, indicating that participants learned the values of the contexts in which rewards were delivered. These results highlight the importance of the ACC in learning the reward values of task contexts in order to guide action selection.

Increases in cAMP, MAPK activity, and CREB phosphorylation during REM sleep: implications for REM sleep and memory consolidation.

The cyclic adenosine monophosphate (cAMP), mitogen-activated protein kinase (MAPK), and cAMP response element-binding protein (CREB) transcriptional pathway is required for consolidation of hippocampus-dependent memory. In mice, this pathway undergoes a circadian oscillation required for memory persistence that reaches a peak during the daytime. Because mice exhibit polyphasic sleep patterns during the day, this suggested the interesting possibility that cAMP, MAPK activity, and CREB phosphorylation may be elevated during sleep. Here, we report that cAMP, phospho-p44/42 MAPK, and phospho-CREB are higher in rapid eye movement (REM) sleep compared with awake mice but are not elevated in non-REM sleep. This peak of activity during REM sleep does not occur in mice lacking calmodulin-stimulated adenylyl cyclases, a mouse strain that learns but cannot consolidate hippocampus-dependent memory. We conclude that a preferential increase in cAMP, MAPK activity, and CREB phosphorylation during REM sleep may contribute to hippocampus-dependent memory consolidation.

[Central EEG rhythm associated with movement and EEG rhythm associated with spatial reasoning: are they homologous?].

EEG rhythmical picture of subject's movement suppression and spatial-figurative task solving was examined and analyzed. Rhythms appearing during spatial reasoning and suppressed movements with the frequency of about 11 Hz were isolated. It was hypothesized that a functional link exists between these rhythms in the considered behavioral tests. To test the hypothesis and to reveal this connection, experiments were developed and carried out. Then the analysis of recorded EEG signals was conducted by applying Fourier transform, independent component analysis (ICA) and equivalent dipole source localization. Unexpected conclusion about the existence of a general mechanism of movement suppression was drawn.

Selective neuronal entrainment to the beat and meter embedded in a musical rhythm.

Fundamental to the experience of music, beat and meter perception refers to the perception of periodicities while listening to music occurring within the frequency range of musical tempo. Here, we explored the spontaneous building of beat and meter hypothesized to emerge from the selective entrainment of neuronal populations at beat and meter frequencies. The electroencephalogram (EEG) was recorded while human participants listened to rhythms consisting of short sounds alternating with silences to induce a spontaneous perception of beat and meter. We found that the rhythmic stimuli elicited multiple steady state-evoked potentials (SS-EPs) observed in the EEG spectrum at frequencies corresponding to the rhythmic pattern envelope. Most importantly, the amplitude of the SS-EPs obtained at beat and meter frequencies were selectively enhanced even though the acoustic energy was not necessarily predominant at these frequencies. Furthermore, accelerating the tempo of the rhythmic stimuli so as to move away from the range of frequencies at which beats are usually perceived impaired the selective enhancement of SS-EPs at these frequencies. The observation that beat- and meter-related SS-EPs are selectively enhanced at frequencies compatible with beat and meter perception indicates that these responses do not merely reflect the physical structure of the sound envelope but, instead, reflect the spontaneous emergence of an internal representation of beat, possibly through a mechanism of selective neuronal entrainment within a resonance frequency range. Taken together, these results suggest that musical rhythms constitute a unique context to gain insight on general mechanisms of entrainment, from the neuronal level to individual level.

Not all errors are alike: theta and alpha EEG dynamics relate to differences in error-processing dynamics.

Performance errors in conflict tasks often result from inappropriate action impulses, and are thought to signal the need for increased control over the motor system. However, errors may also result from lapses in sustained attention, which may require different monitoring and adaptation mechanisms. Distinguishing between the mechanisms of adaptation is important as both error types may occur intermixed. To this end, we measured EEG of healthy human subjects while they performed three variants of the Simon task in which errors were more likely to occur due to attentional lapses, failures of motor control, or both. Behavioral results showed that subjects exhibited less conflict effects and less impulsive errors in sustained attention compared with the other Simon conditions. Time-frequency analyses of EEG data showed that the sustained attention Simon condition, compared with the motor control Simon condition, was characterized by: (1) less error-related MFC theta (4-8 Hz) power and an absence of error-related MFC-DLPFC theta phase synchronization; (2) stronger error-related suppression of parieto-occipital alpha (8-12 Hz) power and stronger parieto-occipital-frontal alpha synchronization. A control experiment, using SART (the Sustained Attention to Response Test), confirmed that adaptation after attentional lapses involved posterior alpha power suppression, in addition to inter-regional frontal theta activity. Together, these results suggest that at least two cortical mechanisms exist for performance monitoring, and that different tasks and task-settings can recruit these mechanisms in a different way. Post-error brain dynamics thus consist of heterogeneous activity from multiple neurocognitive processes.

Persistent cognitive impairment, hippocampal atrophy and EEG changes in sepsis survivors.

OBJECTIVES: The objective of this preliminary study was to explore long-term changes in neurobehavioral parameters, brain morphology and electroencephalography of sepsis patients who received intensive care compared to non-septic intensive care unit (ICU) patients. METHODS: Two-centre follow-up study 6-24 months after discharge from hospital using published norms and existing databases of healthy controls for comparison. Patients included 25 septic and 19 non-septic ICU survivors who were recruited from two ICUs of a university and community hospital. Measurements used include brain morphology, standard electroencephalography, cognition and psychiatric health and health-related quality of life. RESULTS: Sepsis survivors showed cognitive deficits in verbal learning and memory and had a significant reduction of left hippocampal volume compared to healthy controls. Moreover, sepsis and to some extent non-septic ICU patients had more low-frequency activity in the EEG indicating unspecific brain dysfunction. No differences were found in health-related quality of life, psychological functioning or depressive symptoms, and depression could be ruled out as a confounding factor. CONCLUSIONS: This study demonstrates permanent cognitive impairment in several domains in both septic and non-septic ICU survivors and unspecific brain dysfunction. In the sepsis group, left-sided hippocampal atrophy was found compared to healthy controls. Further study is needed to clarify what contribution sepsis and other factors at the ICU make to these outcomes. Specific neuroprotective therapies are warranted to prevent persisting brain changes in ICU patients.

The role of stress as a trigger for epileptic seizures: a narrative review of evidence from human and animal studies.

Stress is one of the most frequently self-identified seizure triggers in patients with epilepsy; however, most previous publications on stress and epilepsy have focused on the role of stress in the initial development of epilepsy. This narrative review explores the causal role of stress in triggering seizures in patients with existing epilepsy. Findings from human studies of psychological stress, as well as of physiologic stress responses in humans and animals, and evidence from nonpharmacologic interventions for epilepsy are considered. The evidence from human studies for stress as a trigger of epileptic seizures is inconclusive. Although retrospective self-report studies show that stress is the most common patient-perceived seizure precipitant, prospective studies have yielded mixed results and studies of life events suggest that stressful experiences only trigger seizures in certain individuals. There is limited evidence suggesting that autonomic arousal can precede seizures. Interventions designed to improve coping with stress reduce seizures in some individuals. Studies of physiologic stress using animal epilepsy models provide more convincing evidence. Exposure to exogenous and endogenous stress mediators has been found to increase epileptic activity in the brain and trigger overt seizures, especially after repeated exposure. In conclusion, stress is likely to exacerbate the susceptibility to epileptic seizures in a subgroup of individuals with epilepsy and may play a role in triggering "spontaneous" seizures. However, there is currently no strong evidence for a close link between stress and seizures in the majority of people with epilepsy, although animal research suggests that such links are likely. Further research is needed into the relationship between stress and seizures and into interventions designed to reduce perceived stress and improve quality of life with epilepsy.

Improving pediatric compliance with EEG: decreasing procedural anxiety and behavioral distress.

Behavioral distress in EEG can be a barrier to medical care, and behavioral interventions may be a solution. This study evaluates the effectiveness of a brief intervention to decrease procedural distress during an EEG. We hypothesized that children and parents who received psychoeducation and distraction interventions would exhibit less anxiety and distress during an EEG procedure, as compared to those receiving standard care, and this would not add to EEG duration. One hundred and thirty-nine children (0-6 years) and their parents referred for routine EEGs were enrolled. Data were analyzed separately for both infants and children due to differences in the presentation of psychoeducational materials. Results demonstrated less parental anxiety and less distress vocalizations during the EEG. Interestingly, the intervention did not increase the duration of the EEG. While the data suggest positive effects, study limitations raise more questions as to the feasibility and impact of psychoeducation and distraction interventions with extended medical procedures.

[Magnetic resonance imaging (MRI) in children and adolescents ­ study design of a feasibility study concerning examination related emotions]. / Magnetresonanztomographie (MRT) bei Kindern und Jugendlichen. Studiendesign einer Durchführbarkeitsstudie hinsichtlichuntersuchungsmethodenbezogener Emotionen.

Numerous research centres apply magnetic resonance imaging (MRI) for research purposes in children. In view of this practical research, ethical concerns regarding the strains the study participants are exposed to during the MRI examination are discussed. The study evaluates whether an MRI examination induces negative emotions in children and adolescents which are more intense than the ones caused by electroencephalography (EEG), an examination method currently classified as causing "minimal stress." Furthermore, the emotional stress induced by the MRI examination in children and adolescents is compared with that induced in adults. The study gathers data on examination-related emotions in children (age 8-17;11, male and female) who undergo an MRI examination of the cerebrum with a medical indication. The comparison group is a sample of children and adolescents examined with EEG (age 8-17;11, male and female) as well as a sample of adults (age 18-65, male and female) examined with MRI. At present, the study is in the stage of data collection. This article presents the study design of the MRI research project.

Pre-attentive modulation of brain responses to tones in coloured-hearing synesthetes.

BACKGROUND: Coloured-hearing (CH) synesthesia is a perceptual phenomenon in which an acoustic stimulus (the inducer) initiates a concurrent colour perception (the concurrent). Individuals with CH synesthesia "see" colours when hearing tones, words, or music; this specific phenomenon suggesting a close relationship between auditory and visual representations. To date, it is still unknown whether the perception of colours is associated with a modulation of brain functions in the inducing brain area, namely in the auditory-related cortex and associated brain areas. In addition, there is an on-going debate as to whether attention to the inducer is necessarily required for eliciting a visual concurrent, or whether the latter can emerge in a pre-attentive fashion. RESULTS: By using the EEG technique in the context of a pre-attentive mismatch negativity (MMN) paradigm, we show that the binding of tones and colours in CH synesthetes is associated with increased MMN amplitudes in response to deviant tones supposed to induce novel concurrent colour perceptions. Most notably, the increased MMN amplitudes we revealed in the CH synesthetes were associated with stronger intracerebral current densities originating from the auditory cortex, parietal cortex, and ventral visual areas. CONCLUSIONS: The automatic binding of tones and colours in CH synesthetes is accompanied by an early pre-attentive process recruiting the auditory cortex, inferior and superior parietal lobules, as well as ventral occipital areas.

Electrophysiological evidence for the understanding of maternal speech by 9-month-old infants.

Early word learning in infants relies on statistical, prosodic, and social cues that support speech segmentation and the attachment of meaning to words. It is debated whether such early word knowledge represents mere associations between sound patterns and visual object features, or reflects referential understanding of words. By measuring an event-related brain potential component known as the N400, we demonstrated that 9-month-old infants can detect the mismatch between an object appearing from behind an occluder and a preceding label with which their mother introduces it. Differential N400 amplitudes have been shown to reflect semantic priming in adults, and its absence in infants has been interpreted as a sign of associative word learning. By setting up a live communicative situation for referring to objects, we demonstrated that a similar priming effect also occurs in young infants. This finding may indicate that word meaning is referential from the outset of word learning and that referential expectation drives, rather than results from, vocabulary acquisition in humans.

Early learning shapes the memory networks for arithmetic: evidence from brain potentials in bilinguals.

Language and math are intertwined during children's learning of arithmetic concepts, but the importance of language in adult arithmetic processing is less clear. To determine whether early learning plays a critical role in the math-language connection in adults, we tested retrieval of simple multiplication in adult bilinguals who learned arithmetic in only one language. We measured electrophysiological and behavioral responses during correctness judgments for problems presented as digits or as number words in Spanish or English. Problems presented in the language in which participants learned arithmetic elicited larger, more graded, and qualitatively different brain responses than did problems presented in participants' other language, and these responses more closely resembled responses for digits, even when participants' other language was more dominant. These findings suggest that the memory networks for simple multiplication are established when arithmetic concepts are first learned and are independent of language dominance in adulthood.

Unresponsiveness ≠ unconsciousness.

Consciousness is subjective experience. During both sleep and anesthesia, consciousness is common, evidenced by dreaming. A defining feature of dreaming is that, while conscious, we do not experience our environment; we are disconnected. Besides inducing behavioral unresponsiveness, a key goal of anesthesia is to prevent the experience of surgery (connected consciousness), by inducing either unconsciousness or disconnection of consciousness from the environment. Review of the isolated forearm technique demonstrates that consciousness, connectedness, and responsiveness uncouple during anesthesia; in clinical conditions, a median 37% of patients demonstrate connected consciousness. We describe potential neurobiological constructs that can explain this phenomenon: during light anesthesia the subcortical mechanisms subserving spontaneous behavioral responsiveness are disabled but information integration within the corticothalamic network continues to produce consciousness, and unperturbed norepinephrinergic signaling maintains connectedness. These concepts emphasize the need for developing anesthetic regimens and depth of anesthesia monitors that specifically target mechanisms of consciousness, connectedness, and responsiveness.

Catatonic disorder due to a general medical or psychiatric condition.

Identification of individuals with catatonic disorder secondary to a general medical condition (CD-GMC) may affect both acute and long-term patient management. The authors performed a 20-year retrospective cohort analysis of all patients meeting DSM-IV-TR criteria for catatonic subtypes seen at our institution. Encephalitis was the most common etiologic diagnosis among patients with CD-GMC, and lumbar puncture the test most likely to affect acute management. Univariate logistic-regression analysis utilizing Bonferroni correction for multiple comparisons yielded absence of a psychiatric history and history of clinical seizure as variables increasing the likelihood of a diagnosis of CD-GMC. Prospective evaluation across a larger patient series will be required to better identify patients with catatonia who would benefit from neurologic evaluation.