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Journal of Clinical EEG & Neuroscience, October, 2009Abstracts of presentations at the 6th Annual Joint Meeting of the EEG and Clinical Neuroscience Society (ECNS) and the International Society for NeuroImaging in Psychiatry (ISNIP), in Atlanta, Georgia, September 9-13, 2009.SymposiaThe Frontal Eye Fields in Parkinson Disease: an fMRI and EEG PerspectiveBodis-Wollner I, SUNY Downstate Medical Center, Brooklyn, USA In Parkinson Disease (PD) several aspects of saccades are affected. The saccade-generating brainstem neurons are spared, however, the signals they receive may be flawed. In particular, voluntary saccades are affected in PD, as in general voluntary and not reflex movements suffer most. We measured blood-oxygenation-level-dependent (BOLD) activation and the wavelet transformed perisaccadic EEG in healthy controls and in moderately advanced, treated PD patients. The functional MRI reveals profound attenuation of frontal eye field activation. Conversely the parietal eye field and the occipital cortex show healthy activation. In the EEG the perisaccadic gamma band shows phasic power increase during the saccade in the posterior electrode sites in healthy controls. In PD patients perisaccadic posterior gamma power remains unmodulated by saccades in PD. The EEG and the BOLD imaging were not obtained concurrently. Further studies are needed to evaluate the role of the frontal eye field in modulating posterior eye field neuronal assemblies in healthy controls and in Parkinson Disease. Partially supported by National Parkinson Foundation (Center of Excellence) and NINDS. The Role of Xenobiotic Agents in EEG Disconnectivity in Autism: a CommentaryCantor DS, Psychological Sciences Institute, Johns Creek, Georgia, USA Autism continues to be labeled as a disorder with increasing incidence in the general population not reaching a ratio of approximately less than 1:150 births. Cantor et al. (1986) first identified qEEG correlates of autism indicating maturational lags in autism principally characterized by deviations in cortical asymmetry and coherence. There have been several papers which have proposed and strongly endorsed that the best descriptor of brain dysfunction in autism is one of “disconnectivity” of neural organization leading to poor coordination of sensory information processing and problems with filtering of sensory information such that identification of habituated versus novelty is hampered. Autism Spectrum Disorders have been documented to include a higher than expected incidence of abnormal immune system functioning and elevated toxins (Xenobiotic Agents). The compounds that have been identified to date have certain impact on cellular mRNA and mitochondrial activity that can alter the normal oscillatory rates of neurotransmitter production and re-uptake in such a way as to have an impact on the “timing” of neural sets to optimally coordinate sensory information. This commentary is intended to integrate some of the findings and models by the speakers of this symposium with a model toward providing an integrated model of etiology. Quantitative EEG Discriminant Functions Between Normal Function and Childhood DisordersChabot RJ, NYU School of Medicine, NY, NY, USA The clinical utility of QEEG in child and adolescent psychiatric disorders including autistic spectrum disorder (ASD), specific developmental disorders, and attention deficit hyperactivity disorder (ADHD) has been documented. We have developed a QEEG database of 310 normal, 458 children with ADHD, 175 with ASD, 59 with dyslexia and 23 with other childhood neurological disorders from 3 separate clinical sites. Using split-half replications we calculated 4 separate discriminant functions. Normal children could be distinguished from all other clinical populations with a sensitivity of 89.0%, specificity of 87.8%, positive predictive value of 75.0%, and negative predictive value of 95.1%. Children with ADHD could be distinguished from the normal child with a sensitivity of 92.9%, a specificity of 90.8%, a positive predictive value of 85.7%, and a negative predictive value of 95.6%. Normal children could be distinguished from children with ASD with a sensitivity of 93.5%, a specificity of 90.1%, a positive predictive value of 94.2%, and a negative predictive value of 89.1%. Children with ADHD could be distinguished from those with ASD with a sensitivity of 84.7%, a specificity of 87.0%, positive predictive value of 70.0%, and a negative predictive value of 94.2%. QEEG variables utilized and ROC curves will be discussed. Nanoproteomics and biomarker discoveryCrawford F, Roskamp Institute, Sarasota, Florida, USA Qualitative and quantitative proteomic approaches afford the ability to characterize in an unbiased manner a large number of proteins, including low abundant proteins, from any biomatrix and are a means by which to identify activation and response of biological and molecular pathways. Protein separation techniques coupled with mass spectrometry and bioinformatic tools are now available which can be potentially useful in bridging the gap between basic science findings and clinical practice. In many diverse fields of study these approaches are now yielding information on pathologic protein responses and are particularly valuable for illnesses with complex pathophysiology that are often difficult to dissect using classical molecular biology approaches. For example, our group currently employs proteomic approaches in animal models of Traumatic Brain Injury, Gulf War Illness and Drug Addiction, to identify biomarkers and novel therapeutics by better understanding the pathogenic molecular processes. Our platform involves isobaric tagging for relative and absolute quantitation (iTRAQ labeling) of fractionated plasma or tissue samples, followed by multidimensional liquid chromatographic separation and mass spectrometry for qualitative and quantitative characterization of the proteome. As these approaches start to yield results, exploring high-efficiency detection methods for proteins of interest will be increasingly important as will improved detection capability and methods to analyze protein-protein interactions. Nanotechnological developments are addressing these and other critical areas for clinical proteomics, allowing increased sensitivity and more accurate monitoring of protein changes, which will further contribute to early diagnosis and identification of therapeutic approaches, as well as offering novel possibilities for targeted drug delivery. This presentation will highlight results from our own analyses and address the potential avenues through which this work can be enhanced using nanotechnology. The Cognitive Circuit of Parkinson’s DiseaseEidelberg D, The Feinstein Institute for Medical Research, Manhasset, NY, USA Network analysis has been used to study the cognitive changes associated with Parkinson’s disease (PD). Voxel-based spatial covariance analysis of metabolic imaging data from non-demented PD patients has revealed a distinct pattern that was related to cognitive dysfunction. This PD-related cognitive pattern (PDCP) is characterized by a covariance structure that was different from the PD-related motor pattern (PDRP), with metabolic reductions mainly in medial frontal and parietal association regions, and relative increases in cerebellar cortex and dentate nuclei. PDCP expression in individual subjects correlated with performance on neuropsychological tests of memory and executive functioning in an original pattern derivation cohort and in a larger prospective validation cohort. Like the PDRP, PDCP expression is highly reproducible in individual patients. Importantly, although the activity of both networks increased linearly as a function of symptom duration, the rate of increase in PDCP expression was slower than that of the PDRP measured in the same subjects. Unlike the PDRP, PDCP expression is not modulated by routine antiparkinsonian therapy with levodopa or STN deep brain stimulation (DBS). Nonetheless, the effects of treatment on cognitive functioning have been found to correlate with baseline PDCP expression. Overall, these cross-sectional studies suggest that different neural systems underlie these two disease-related metabolic networks. BOLD fMRI Investigations of Cortical Plasticity in Former Hand AmputeesFrey SH, Lewis Center for Neuroimaging, University of Oregon, Eugene, Oregon, USA Evidence from multiple levels of analysis supports the hypothesis that the functional organization of cortical sensory maps is activity dependent. Deafferenting injuries, including amputation, induce a cascade of reorganizational events that begin almost immediately, continue for months or longer, and culminate in significantly altered map topography. Can restoration of afferent signals reverse the effects of chronic deafferentiation? The answer to this question holds important implications for our basic understanding of the brain and is also of great clinical significance. Allogeneic hand transplant recipients present a unique opportunity to address this critical question. In this talk I will discuss our work using high resolution BOLD fMRI to address the emerging cortical representations of transplanted hands in former amputees. I will make the case that, even after long periods of deafferentiation, the mature cerebral cortex possesses a remarkable ability to return to its pre-amputation state. And, along with these changes come striking levels of functional recovery. Potential mechanisms underlying this phenomenon will be considered and the broader implications of these findings for our understanding and treatment of deafferenting injuries will be discussed. Processing Emotions in Anxiety and Mood Disorders: ERP and Neuroimaging FindingsGalderisi S, University of Naples SUN, Naples, Italy Abnormalities of emotion processing have been reported in both anxiety and mood disorders. It has been proposed that anxiety is related to abnormally increased fear response, which in its turn might be due to disordered pre-attentive fear response, or to reduced efficiency of late modulatory processes. Depression might involve abnormalities of reward responsiveness. Behavioral and neuroimaging findings allowed the identification of brain circuits involved in fear processing and response to reward. In this symposium, Aminda O’Hare will present the results of a study investigating the ERP correlates of anxious arousal in 58 healthy students; Avram Holmes will describe a study on impaired reward responsiveness following error commission in 18 patients with major depressive disorders compared to controls; Armida Mucci will illustrate the results of an ERP study on involuntary emotional processing in 33 healthy volunteers, and 55 clinically stable patients with different anxiety or mood disorders; and Jason S. Moser will present ERP findings on early (attention-related) and late (response-related) emotion face biases in social phobia and depression. Application of Nanotechnologies for Real-time Imaging During Neurosurgery Grundfest W, Culjat M, University of California, Los Angeles, California, USA Several advances in imaging technology are now feasible based on the applications of nanotechnology to intraoperative imaging. The development of tumor-targeted, fluorescently-labeled nanoparticles may allow for real-time intraoperative delineation of tumor margins. A variety of nanoparticles based on single-wall carbon nanotubes, silica nanoparticles, and gold nanoshells have been reported. Many of these particles are designed for both tumor identification and therapy. These modalities require direct optical imaging. At the same time, real-time ultrasonic guidance using flexible conformable ultrasound arrays may permit direct intraoperative guidance during surgery and allow greater precision during access to intracranial lesions. These thin film flexible arrays use PLZT elements (100 microns thick X 1mm2) mounted on flexible polyamide substrates to generate and receive ultrasonic signals. These arrays can be introduced through small burrholes, facilitating less invasive approaches. Multi-element arrays of various sizes can be constructed to permit acquisition of 3D images capable of 0.5mm resolution at a depth of 2cm-5cm. As these technologies are developed less invasive approaches will become feasible. Electrophysiological Correlates of Error Commission in Major Depressive Disorder: Dissociable Effects of Task-Relevant IncentivesHolmes AJ, Pizzagalli DA, Harvard University, Cambridge, Massachusetts, USA Reduced reward responsiveness and impaired behavioral performance following error commission has been observed in patients with major depressive disorder (MDD). We examined the electrophysiological correlates of error commission (error-related negativity, ERN; error positivity, Pe) in participants with MDD (n=18) and healthy controls (n=18) during the completion of a Stroop task featuring no-incentive and monetarily rewarding trials. Replicating prior findings, participants with MDD exhibited increased ERN amplitudes on no-incentive trials. Following errors on reward trials, the MDD group exhibited reduced Pe compared to controls, no group differences in ERN emerged. Among MDD participants, Pe amplitudes were negatively correlated with self-reported depressive symptomatology. No-incentive trial ERN group differences could result from heightened, condition independent, amplitudes in MDD participants. While healthy controls attribute increased significance to errors committed when rewards are available, the relative impact of these errors might be smaller in participants with MDD, possibly due to apathy and/or anhedonia. These deficits become apparent in MDD when monetary incentives are made available, and the relationship between anhedonia and action monitoring is explicitly probed. The present findings indicate that MDD is associated with a heightened reactivity to error commission, which is reduced in the context of increased incentives. Deep Brain Stimulation for Treatment-Resistant DepressionHoltzheimer PE, Emory University SOM, Atlanta, Georgia, USA Deep brain stimulation (DBS) is emerging as a promising treatment for many neuropsychiatric conditions, including treatment-resistant depression (TRD). In this presentation, the development of subcallosal cingulate (SCC) DBS will be described including: (1) review of the neuroimaging and other data supporting Brodmann Area (25) within the SCC as a crucial node within a neural network implicated in depression and the antidepressant treatment response; (2) discussion of the rationale for DBS as a means of modulating this node and the broader network; (3) a summary of preliminary safety, efficacy and mechanism of action studies of SCC DBS for TRD; and (4) brief delineation of critical questions that should be addressed as this intervention develops. Application of NASA’s Pristine Multi-Wall Carbon Nanotubes (MWCNTs) in Brain Tumor Immune TherapyKateb B, International Brain Mapping & Intraoperative Surgical Planning Society (IBMISPS), West Hollywood, California, USA Carbon nantotubes (CNTs) are emerging as a new family of nanovectors for drug and gene delivery into biological systems. To evaluate potential application of this technology for brain tumor therapy, we studied uptake and toxicity of multi-walled CNTs (MWCNTs) invitro and invivo (in the GL261 murine intracranial glioma model). The invite study demonstrated that MWCNTs do not result in proliferative or cytokine changes in vitro, are capable of carrying DNA and siRNA and are internalized at higher levels in phagocytic cells as compared to tumor cells. The Invivo study showed that within 24 h of a single intratumoral injection of labeled MWCNTs (5 Ìg), nearly 10-20% of total cells demonstrated CNT internalization. Most CNT uptake, however, occurred by tumor-associated macrophages (MP), which accounted for most (75%) MWCNT-positive cells. Within 24 h of injection, nearly 30% of tumor MP became MWCNT-positive. Despite a transient increase in inflammatory cell infiltration into both normal and tumorbearing brains following MWCNT injection, no significant toxicity was noted in mice, and minor changes in tumor cytokine expression were observed. This study suggests that MWCNTs could potentially be used as a novel and non-toxic vehicle for targeting MP in brain tumors. Nano-Engineered Bioscaffolds for Neural RepairLi S, University of California, Berkeley, California, USA Nanofibrous scaffolds can provide guidance for axon growth, and have tremendous potential as a platform for drug delivery and cell therapies. Here we show that nanofibrous conduits with aligned nanofibers in the longitudinal direction promote axon growth ex vivo and facilitate the regeneration of sciatic nerve in rat model. In addition, nanofibrous scaffolds were used as patches to deliver rolipram to spinal cord tissue with hemisection injury. The nanofibrous scaffolds enhanced axon growth and angiogenesis and promote the recovery of limb function. Should We Be Worried About Cognitive Declines Following Deep Brain Stimulation?Mikos A, Bowers D, Okun MS, University of Florida Movement Disorders Center, Mcknight Brain Institute, Gainesville, Florida, USA Deep Brain Stimulation (DBS) surgery of the subthalamic nucleus (STN) has been utilized to address medication-refractory Parkinson disease (PD), however there have been documented cognitive sequalae. We report a cohort of unilateral STN DBS patients who performed verbal fluency tasks with stimulation of the contact that provided optimal motor benefit, as well as with stimulation of the contacts dorsal and ventral to that and OFF stimulation. Testing occurred “off” dopa medication. Computer-generated models of activated tissue were created for each contact based upon anatomical, electrical, and neural activation information. Outcome measures included the volume of tissue activation (VTA), and the amount of VTA occurring both inside and outside of the STN. Spearman correlations were conducted. At dorsal contacts, more VTA outside of the STN was related to lower category fluency scores relative to OFF stimulation. At ventral contacts, more VTA inside the STN was related to lower letter fluency scores relative to OFF stimulation. This study suggests that stimulation dorsal to and outside of the STN, as well as ventrally within the STN may adversely affect verbal fluency performance. These findings will be discussed in the larger context of cognitive declines with DBS. Support provided by NIH and the National Parkinson Foundation. Anatomical and Functional MRI Contributions to the Understanding of Parkinson’s DiseaseMonchi O, Montreal Geriatric’s Institute and University of Montreal, Canada The degeneration of nigrostriatal neurons as the quasi-unique origin of Parkinson’s disease (PD) pathophysiology has recently been challenged. Furthermore, the effects of L-Dopa therapy on the cognitive deficits are not well understood. We initially compared patients at the early stages of PD (off medication) with control participants using fMRI during the performance of the Wisconsin Card Sorting Task. The results showed that the cortical activity in PD depends on the striatal involvement for the task, with less cortical activation if the striatum is solicited and more if it is not. More recently, we used the same protocol on PD patients that were scanned twice, once taking their usual dose of dopaminergic medication and another time following overnight removal of medication. The results indicate that L-Dopa has significantly more effect on motor cortico-striatal regions than on cognitive areas such as the prefrontal cortex. In a last study novel anatomical MRI methods are being used to identify anatomical differences between PD patients and healthy individuals. Preliminary results show a significant reduction in tissue intensity in the brain stem of PD patients using optimized VBM, in accordance with post-mortem studies suggesting this region as the first damaged cite in the disease pre-symptomatically. Information Processing Biases in Social Anxiety as Revealed by Event-Related Brain PotentialsMoser JS, University of Delaware, Newark, Delaware, USA In the present talk, I will present event related brain potential (ERP) findings from two paradigms – an ambiguous sentence processing task and a modified version of the Eriksen Flanker task using facial stimuli (face flanker task) – employed across three experiments aimed at further elucidating the nature and temporal dynamics of information processing biases in social anxiety. In Experiment 1, high socially anxious subjects lacked the positive interpretation bias shown by low anxious subjects in the ambiguous sentence processing task. In Experiment 2, high socially anxious subjects showed dynamic biases reflected in a lack of positive face bias and presence of a negative face bias in the face flanker task. In Experiment 3, we extended our findings to socially phobic and depressed patients. Findings from the ambiguous sentence task revealed a common interpretation bias in social phobia and depression. The face flanker task, on the other hand, showed distinct emotion face biases between social phobia and depression, such that social phobics were characterized by early attention-related face biases while depressives were characterized by later response-related face biases. Implications of these findings for research and theory of information processing biases in social anxiety and negative affective psychopathology will be considered. ERP Indices of Involuntary Emotional Processing in Anxiety and Mood DisordersMucci A, Centanaro F, Russo D, Galderisi S, University of Naples SUN, Naples, Italy Abnormalities of emotion processing have been reported in both anxiety and mood disorders. It has been proposed that anxiety is related to abnormally increased fear response, which in its turn might be due to disordered pre-attentive fear response, or to reduced efficiency of late modulatory processes. Depression might involve reduced responsiveness to positive emotions. Event-related potentials (ERPs) can be used to explore the time course of emotional processing to better understand both normal and disordered emotional processing. In the present study, ERPs were used to investigate involuntary emotional processing in 33 healthy volunteers, and clinically stable patients with anxiety or mood disorders (16 with panic disorder, PD, 15 with obsessive-compulsive disorder, OCD, 13 with unipolar depression, UD, and 11 with bipolar disorder, BD). ERPs were recorded during a target detection task. Erotic, threatening, disgusting and neutral stimuli were used as distracters. Stabilized patients with anxiety and mood disorders differed from controls in the sequence, duration and topography of ERP components elicited by emotional distracters. Only patients with BD differed on the same ERP parameters for target stimuli. Abnormalities of emotional processing might represent a trait factor in both anxiety and mood disorders. ERP Components as Indices of Anxious ArousalO’Hare A, University of Kansas, Lawrence, Kansas, USA Working within the framework of the dual-anxiety model, it has been argued that different types of anxiety can be differentiated behaviorally, cognitively, and in brain laterality (Heller, Nitschke, Etienne, & Miller, 1997). Anxious arousal and anxious apprehension have been proposed to be two aspects of anxiety that are differentially lateralized. Two prior event-related potential (ERP) studies have found right-lateralized ERPs that correlate with scores on the Fear Survey Schedule (FSS) but not with the Spielberger State-Trait Anxiety Inventory (STAI), seeming to indicate ERP components more sensitive to characteristics of anxious arousal than anxious apprehension. Here, work by the author will be presented that provides further support for differing lateralities in the dual-anxiety model. High-density ERPs were recorded from 58 participants who completed the STAI and FSS as measures of trait anxious apprehension and anxious arousal, respectively. A spatial cueing task where emotional faces validly or invalidly cued targets was used. A right-lateralized posterior component responsive to scores on the FSS was revealed. This finding supports the idea that anxious arousal can be right lateralized. Event-Related Potentials and Neuroimaging in Psychiatry – Implications for Diagnosis and TreatmentPogarell O, Ludwig-Maximilian University, Munich, Germany The neurobiological characterization of patients is a major issue in psychiatry. Clear pathophysiological hypotheses with respect to brain activity or metabolism provide the scientific basis for neuropsychopharmacological approaches. The effects of psychoactive agents often depend on a reliable differentiation of the subjects neurochemical properties. Both neurophysiological and functional neuroimaging techniques have been used to discriminate diagnostic and therapeutic subgroups of neuropsychiatric patients and have been investigated regarding prognostic and predictive properties. Different methodological approaches will be presented and discussed in terms of their clinical implications. Electroencephalography has been used for studying the cortical effects of psychoactive drugs and to predict response to medication in different neuropsychiatric conditions. Functional MRI and electroencephalography can be integrated and implemented to assess brain functional abnormalities, which might be relevant for therapeutic decisions in psychiatry. Molecular imaging with radioligands of serotonergic and dopaminergic pathways in combination with neurophysiological tools allow the stratification of neuropsychiatric patients with respect to brain neurochemical properties which might be predictive for the individuals’ responses to medication. Both methodological and clinical studies using these techniques alone or in combination will be presented and discussed with a special focus on their clinical applications for diagnosis and treatment in neuropsychiatric disorders. Electrophysiological Neuroimaging in Diagnosis and Treatment of Generalized Anxiety Disorder – Evidence for a Key-Lock PrincipleSaletu B, Anderer P, Assandri A, Stefano AD, Vaccani A, Nannipieri F, Saletu-Zyhlarz GM Medical University of Vienna, Austria, Cross Research, Arzo, Switzerland and Abiogen Pharma, Pisa, Italy Quantitative analyses of the electroencephalogram (EEG), including EEG mapping and EEG tomography such as low-resolution brain electromagnetic tomography (LORETA), have been utilized to gain insight into the pathogenesis of psychiatric disorders such as generalized anxiety disorder (GAD), but also into the mode of action of psychotropic drugs. Earlier LORETA studies in 44 patients with nonorganic insomnia (F51.0) and comorbid GAD (F41.1) (HAMA: 22±6, SAS: 37±6, sleep efficiency index: 84±12%) compared with controls showed an increase in LORETA power in the delta, theta, alpha-1 and alpha-2 frequencies, while an anxiolytic sedative (lorazepam + diphenhydramine) induced opposite changes after 4-week treatment vs. pre-drug placebo. In contrast, a recent study in GAD patients without mandatory insomnia (n: 18, HAMA: 26±5, SAS: 41±8, sleep efficiency index: 88±8%) compared with controls demonstrated a deficit of LORETA power – specifically in delta (more left than right hemisphere, involving occipital cortex, insula, cingulate and frontal cortex) and beta (occipital cortex), mirroring neuroimaging findings on the neural circuitry of anxiety. Oppositional changes were seen during treatment with ABIO-08/01, a novel GABAergic anxiolytic with cognition-enhancing and anticonvulsive properties. Thus, both studies demonstrated a key-lock principle as the changes induced by the drugs were opposite to those caused by the disorders. Clinical, Polysomnographic and EEG-LORETA Studies in Somatoform Pain Disorder With Comorbid Nonorganic InsomniaSaletu-Zyhlarz G, Prause W, Aigner M, Anderer P, Grätzhofer E, Klug S, Saletu B, Medical University of Vienna, Austria Somatoform pain disorder (SPD) is frequently associated with insomnia, which in turn lowers the pain threshold and worsens pain. The aim of this study was to investigate differences in wake-EEG (LORETA) and objective and subjective sleep and awakening quality in SPD patients as compared with controls and study acute and chronic effects of trazodone CR on these variables and pain measures. Fifteen patients with SPD (F45.4) and co-morbid insomnia (F51.0) were compared with 15 controls and participated in a single-blind, placebo-controlled, cross-over study on the acute effect of 100 mg trazodone CR, followed by a six-week open titration period. Statistics involved clinical, EEG-LORETA, PSG and psychometry. LORETA showed reduced power, mainly in the beta band in almost all pain matrix areas (SI, SII, ACC, SMA, PFC, PPC, insula, amygdala, hippocampus). PSG demonstrated a lack of deep sleep and increased arousals and stage shifts, with opposite changes induced by trazodone after acute and chronic therapy. Improvement of sleep was associated with improvement of pain. In conclusion, our LORETA findings demonstrate a dysfunctional pain modulation in SPD. Trazodone induced changes in subjective and objective sleep and awakening quality that were opposite to the differences between SPD patients and controls (key-lock principle) and associated with pain improvement. Viral Etiologies for Selected Neuropsychiatric Disorders: Lessons from the past … Hopes and implications for the futureSmith RW, Institute for Postgraduate Interdisciplinary Studies, Palo Alto, California, USA Stress-activated virus secondary particles (dubbed autovirions) are putative etiologic factors in autism spectrum disorders, schizophrenia and selected other neuropsychiatric conditions. This recent discovery reveals new “epigenetic” ways for conceptualizing genetic and psychiatric disorders, their development and consequences. Autovirions effectively interfere with or change the ‘genetic code’, even without changing host genes or DNA sequences. Our findings reveal reasons why some common latent viruses may contribute to uncommon and enigmatic diseases and syndromes by means of “hit-and-run” and “beneath-the-radar” actions. Perhaps more important, this discovery provides additional parsimony that now can explain associations among autoimmune diseases, infectious diseases, some cancers, and many disparate and long-term psychoimmunoneurological consequences. This report examines new opportunities for assessing, treating and preventing neurobehavioral disorders and their seemingly unrelated symptoms and consequences. Also discussed are experimental and epidemiologic approaches and technologies likely to contribute to the further explication and elucidation of genetic, genomic and psychiatric illnesses. Dopamine, Reward, and Frontostriatal Circuitry in Impulse Control Disorders in Parkinson’s Disease: Insights from Functional ImagingStrafella A, University of Toronto, Canada In the last few years, Impulse Control Disorders (ICD) are increasingly reported in Parkinson’s disease (PD) patients on dopamine agonists. Given the social implications, these disorders represent a cause of significant distress not only for the patients but also their families. A number of studies have reported over the past few years the significant contribution of dopamine in addiction. There are reasons to believe that behavioral forms of addictions may share the same neural network of the well described drug addiction. However, to date, the mechanisms underlying behavior addictions in PD are poorly understood. Proposed mechanisms include abnormal functioning of mesolimbic structures resulting in dysregulation of striatal dopamine. In this presentation, we will review neural networks, imaging abnormalities and dopamine and genetic contribution in ICD. Quantitative EEG Evaluations of Childhood Disorders Including Measures of Cross-Frequency Phase Synchrony and the Development of EEG Phase ResetThatcher RW, North DM and Biver CJ, Applied Neuroscience Research Institute, St. Petersburg, Florida, USA A systematic evaluation of the electrical fields of the brain of children from age 2 months to 16 years of age using quantitative electroencephalography will be presented. Automatic artifact removal and visual verification of artifact free EEG will be demonstrated. Comparisons to FDA registered normative databases will be emphasized in an effort to link a child’s symptoms and complaints to functional localization of function. The location of deviant electrical activity is evaluated with multiple methods including surface electrical field analysis, Laplacian current source density, coherence, bi-spectral analyses and phase reset. Then a 3-Dimensional analysis of deviant current sources with respect to an age match normative database is used to further link patient’s symptoms and complaints to functional localization in the brain. These methods have been used in hundreds of cases and some examples will be presented, including analyses from autistic children. In addition, the evaluation of cross-frequency phase shift and cross-frequency phase lock will be presented to evaluate thalamo-cortical dysrhythmia and other dysfunctions of the brain. Publications on the development of thalamo-cortical phase shift and phase lock from birth to age 16 will also be presented. Quantum Dot Nanotechnologies for Probing Receptor Trafficking in the Nervous SystemVu T, Oregon Health & Sciences University, Portland, Oregon, USA Emerging theories suggest that the intracellular trafficking of receptors may play a fundamental role in neural signaling. Moreover, impaired receptor trafficking in neurons is hypothesized to be involved in the pathogenesis and progression of a spectrum of neurodegenerative diseases (e.g. Alzheimer’s, major depression, ALS). A detailed and integrative understanding of how neurons traffic at the molecular level is however surprisingly sparse. One difficulty in studying the role of receptor trafficking in healthy and diseased neurons is due to a lack of an imaging probe capable of quantifying the behavior of a sequence of a diverse population of individual receptor molecules undergoing simultaneous complex dynamics and biochemical interactions. Here I will present work showing how a suite of quantum dot-based assays that we have developed can be applied to elucidate the role of receptor trafficking in neural signaling. These quantum dot-based assays can be used to study the molecular dynamics of biochemical signaling in neurons in both in vitro and in vivo experimental preparations. Free Oral Communications40Hz Oscillations (LORETA Source Analysis): Male/Female Differences in Depression, Mania, Schizophrenia and ControlsFlor-Henry P, Lind J, Koles Z, Alberta Hospital Edmonton, University of Alberta, Canada Among those studied were 65 male controls, 80 female controls, 44 female depressives, 31 male depressives, 15 female manics, 11 male manics, 18 female schizophrenics, 69 male schizophrenics. All patients were unmedicated. Quantitative EEG analyses were carried out with 48 electrodes system during four conditions: Eyes Open, Eyes Closed, Dot Localization and Word Finding. It was found that in the 40Hz band: in normals males have increased sources in the left and females have increased sources in the right hemisphere; compared to controls female depressives had predominantly left hemispheric sources whereas male depressives had predominantly right hemispheric sources; both male and female manics had predominantly left hemispheric sources when compared to controls, male schizophrenics (including sinistrals and ambilaterals), when compared to controls, had increased left hemispheric sources whilst consistent dextral male schizophrenics showed increased right hemispheric sources; when female schizophrenics are compared to female controls it is the controls who have increased sources in the right hemisphere. In depression, mania and schizophrenia there are changes in lateral hemispheric (dis)organization which, in each of the 3 psychosis, are gender dependent. Alpha Phase Synchrony Model of Consciousness: Clinical ApplicationsHebert R, Tan G, Michael E. DeBakey Veterans Affairs Medical Center, Houston, Texas, USA Our previous report (Hebert, 2005) identified two types of alpha standing waves. The new in-phase waveform found in transcendental meditation was associated with a content-free “ground state” hypothesized by Roy John (2002). We evaluated the wavelength of alpha as a possible physical explanation for these standing waves. We used 1) Neurorep QEEG that allows the millisecond measure of a half cycle of alpha 2) application of “wavelength formula” consisting of frequency of alpha, cortical travel distance and traveling speed. We determined the wavelength of alpha to be ~50-cm; half a cycle=25 cm, =A-P length of the cortex favorable for standing waves. Our “phase synchrony model of consciousness” describes alpha phase synchrony in the context of phase reset, evoked potential, comparator processing, traveling waves, standing waves, memory access, perceptual frames and cross-frequency phase synchrony. We describe how in-phase standing wave alpha may provide a restorative mechanism we call the “rebooting operating system”. These new-found alpha roles may explain the negative clinical impact of low alpha phase synchrony. We propose the enhancement of alpha through the EEG-based ground state as a method of restoring homeostasis in brain function. As John (2002) hypothesized: “when the ground state is restored..psychiatric disorders often normalize”. Subanesthetic Dose of Ketamine Decreases Prefrontal Theta-Cordance in Healthy Volunteers: Implications for Antidepressant Effect Horacek J, Brunovsky M, Novak T, Tislerova B, Spaniel F, Mohr P, Balikova M, Hoschl C Theta-cordance is a novel clinically highly relevant quantitative electroencephalography measure that correlates with cerebral perfusion. A series of clinical studies demonstrated that the prefrontal theta-cordance value decreases after one week of treatment in responders to antidepressants and that this effect precedes clinical improvement. Ketamine, a non-competitive antagonist of N-methyl-D-aspartate (NMDA) receptors, has a unique rapid antidepressant effect but its influence on theta-cordance is still unknown. In an acute double-blind, cross-over, placebo-controlled experiment we studied the influence of ketamine (0.54 mg/kg within 30 min) on theta-cordance in a group of 20 healthy volunteers. Ketamine infusion induced a decrease in prefrontal theta-cordance and increase in the central region theta-cordance after 10 and 30 min. The change of prefrontal theta-cordance correlates with ketamine and norketamine blood levels after 10 min of ketamine infusion. In conclusion, our data indicate that ketamine infusion immediately induces similar changes as monoamineric-based antidepressants do gradually. The reduction in theta-cordance could be a marker and predictor of a fast antidepressant effect of ketamine, a hypothesis that could be tested in depressive patients treated with ketamine. Early Auditory Gamma Band Response Abnormalities in First Hospitalized Schizophrenia Taylor GW, McCarley RW, Salisbury DF, Harvard Medical School, Boston, Massachusetts, USA Recent theory suggests abnormalities in the coherent function of cortical cells in local and distributed processing assemblies through synchronous firing in the gamma range may be a core neurophysiologic deficit in schizophrenia. Although several recent studies have noted gamma band abnormalities to complex second order transforms in the visual system or to exogenously driven auditory gamma function, an endogenous gamma burst occurs early within the auditory system that may serve as a simple probe of coherent cortical circuit functioning in the disorder. This early auditory gamma band response (EAGBR), due to its occurrence early in the processing stream, is easily dissectible and localized to primary auditory structures. To determine if the EAGBR was abnormal in power and trial-to-trial phase locking, 24 first hospitalized schizophrenia and schizoaffective patients and 32 matched control subjects were compared on the EAGBR to standard tones recorded during an oddball target detection task. Abnormalities in the coherent functioning of local cell assemblies within primary auditory cortex are apparent in schizophrenia even near psychosis onset. This supports the contention that basic sensory processes are impaired in schizophrenia Enhanced Intensity Dependence and Aggressive Behavior History Indicate Previous Ecstasy Use in Abstinent Polydrug Users Wan L, Baldridge RM, Colby AM, Stanford MS, Baylor University, Waco, Texas, USA Intensity dependence is an electrophysiological measure of intra-individual stability of the augmenting/reducing characteristic of the N1/ P2 event-related potential amplitudes in response to stimuli of varying intensities. Ecstasy (MDMA, MDA, and MDEA) is a group of popular recreational drugs. Abstinent ecstasy users typically show enhanced intensity dependence and higher levels of impulsivity and aggression. Enhanced intensity dependence and high impulsivity and aggression levels may be due to damage in the brain’s serotonergic neurons as a result of ecstasy use. The present study investigated whether intensity dependence, impulsivity and aggressive behavior history can be used as indictors of previous ecstasy usage. Forty-four abstinent polydrug users (8 women; age 19 to 61 years old) were recruited. All participants were currently residents at a local substance abuse facility receiving treatment and had been free of all drugs for a minimum of 21 days. The study found significantly enhanced intensity dependence of tangential dipole source activity and more aggressive behavior history in participants who had used ecstasy before. Intensity dependence of the tangential dipole source and aggressive behavior history correctly identified 73.3% of those who had used ecstasy and 78.3% of those who had not. Overall, 76.3% of the participants were correctly classified. PostersAssessment of Mismatch Negativity in Auditory Sensory Gating ParadigmsAfifi S, Gjini K, Burroughs S, Elfakhani M, Boutros NN, Wayne State University, School of Medicine, Detroit, Michigan, USA Mismatch negativity (MMN) is an evoked response related to automatic probing of auditory sensory traces of a repetitious stimulus by a deviant one elicited in an oddball paradigm. We aimed to assess MMN-like activity in five different auditory sensory gating (SG) paradigms in schizophrenia patients and healthy controls. Twenty-five schizophrenia patients and 29 healthy controls were enrolled in the study. Five SG paradigms were used: a paired-stimulus paradigm with identical stimuli (S1=S2), two paired-stimulus paradigms with deviant pitch for second stimuli (S1>S2 or S1<S2) and two short-train paradigms with 5 identical stimuli followed by a sixth deviant stimulus (S1-S5). Interstimulus and interpair / intertrain interval were set to 0.5s and 8s, respectively. Mismatch negativity was scored from the difference waves (S2 -S1 in paired stimulus and S6-S5 in the short-train paradigms) at Fz electrode site. Repeated measures ANOVA statistics showed a main effect of task (F=2.16, p=0.086) and task group interaction (F=2.57, p=0.049). MMN amplitudes differed significantly between groups in two paired standard-deviant paradigms, but not in paired identical-click and short-train paradigms. These preliminary results should be extended further in studying the inter-relationship between MMN-like responses and habituation / dishabituation effects in auditory sensory gating (SG) paradigms, especially during the stimuli processing represented by N100 and P200 AEP components. Neuroendocrinal Study of Depression in Epileptic Patients Afifi S,Sandhu R, Boutros N, Wayne State University, School of Medicine, Detroit, Michigan, USA Depressive Disorders are the most common type of psychiatric co-morbidity in patients with epilepsy. It is more prevalent in patients with partial seizures than with generalized epilepsy. The interrelationship between mood and endocrine changes is not well characterized. Forty patients; 20 depressed epileptics and 20 non-depressed epileptics were examined. Every subject had an electroencephalogram (EEG), Hamilton Depression Rating Scale (HDRS), and serum level of cortisone, prolactin, thyroid (T3, T4, TSH), and testosterone levels. Patients were drug-free and without endocrinological disorders. Significant elevations of prolactin and cortisone were found in depressed epileptic patients as compared to non-depressed epileptics (P=0.0005). Significant decrease in testosterone was also noted in depressed as compared to non-depressed epileptic patients (P=0.0005). There was no significant differences between the two groups regarding thyroid hormones. Epilepsy is a chronic neurological disorder which leads to hormonal storm after the occurrence of fits. These changes are commonly present in association with interictal depression which is characterized by increased serum prolactin and cortisone and decreased serum testosterone with no effect on the thyroid hormones. Further examination of this relationship could shed additional light on the etiology of depression in epileptics. The Reduction of Prefrontal QEEG Theta Cordance as a Predictor of Treatment Response in Patients With Resistant Major Depression: a Pooled Analysis of Single-Center Studies With Bupropion, Venlafaxine and rTMSBrunovsky M, Bares M, Novak T, Kopecek M, Horacek J, Krajca V, Höschl C, Prague Psychiatric Center, Charles University, Czech Republic Cordance is a measure that combines complementary information from absolute and relative power of EEG spectra. Previous studies have shown that decrease in prefrontal theta cordance after first week of treatment can predict clinical response in unipolar depression. This pooled analysis compared the efficacy of cordance in the prediction of response in patients with resistant depression. Data from a 4-week, open-label study of bupropion (n=18) and a 4-week, two-arm, double-blind, randomized trial of venlafaxine (n=26) and 1 Hz rTMS (n=26) were pooled and analyzed for all patients. Prefrontal theta band cordance was computed at baseline and after one week of treatment. Depressive symptoms were assessed using Montgomery-Åsberg Depression Rating Scale (MADRS). There was no significant difference across 3 treatment groups in the rate of response; 28 of 31 responders (reduction of MADRS?50%) and 12 of 39 non-responders showed decreased prefrontal QEEG cordance after 1 week of treatment (p=0.01). The predictor yielded accuracy of 79% (90% sensitivity, 69% specificity) with positive and negative predictive values of 0.7 (95% CI, 0.56-0.84) and 0.9 (95% CI, 0.80-0.99), respectively. Effects of Child Abuse and/or Neglect on Hippocampal Volumes in First Episode Psychosis PatientsCharil A, Czechowska Y, Malla A, Joober R, Laplante DP, King S, McGill University, Montreal, Canada Research has demonstrated that there exists a high prevalence of childhood trauma in patients with schizophrenia. MRI studies generally show a reduction of hippocampal volume in patients with schizophrenia. However, the relationship between childhood trauma (abuse and neglect) and hippocampal volumes in schizophrenic patients has yet to be determined. The present study examined the relationship between child abuse and/or neglect and hippocampal development. Thirty-five first episode psychosis patients (23 men, 12 women; mean age=23, range=18-30) were assessed for childhood abuse/neglect, by means of the Childhood Trauma Questionnaire (CTQ), and structural brain anomalies by means of T1-weighted structural MRIs at 1.5T (3D spoiled gradient echo acquisition; 1mm isotropic voxels). Following nonuniformity correction, registration into standard stereotaxic space, and signal intensity normalization the left and right hippocampi (total, body, head, and tail) were manually segmented according to the protocol described by Pruessner et al. (2000; updated protocol by Pruessner, unpublished data, 2006). Significant positive correlations were found between right HC tail and CTQ Abuse for men (r=.48; p=.019), and between both left (r=.85; p=.001) and right (r=.87; p<.001) HC heads and CTQ Neglect for women, suggesting that different HC regions are associated with different types of childhood trauma in men and women. The Cortical Silent Period is Abnormal in Abstinent Cocaine-Dependent IndividualsElfakhani M, Gjini K, Burroughs S, Boutros N, Wayne State University, School of Medicine, Detroit, Michigan, USA The cortical silent period (CSP) elicited by transcranial magnetic stimulation (TMS) of the motor cortex is altered in neuropsychiatric disorders and modulated by drugs including dopamine. We aimed to know the effects of cocaine, a dopamine-related drug, on the human brain using a sensori-motor clinical neurophysiologic battery. In five abstinent cocaine-dependent subjects, and five control gender- and age-matched, EMG was recorded from the first dorsal interosseous and a figure-eight coil was used to stimulate the right and left M1. For CSP, five trials of single TMS obtained from 100 to 150% of AMT were averaged and rectified. Mid-latency auditory evoked responses also recorded will be presented separately. CSP was significantly longer (range: 80.3 to 176.2ms) in abstinent cocaine-dependent subjects than in controls (range: 67.8 to 128.2ms ) at all intensities of stimulation, and in both hemispheres (P<0.01 at all values). In conclusion, the CSP is prolonged by the administration of L-DOPA in normal subjects and shortened by neuroleptics. This is the first report of significant prolongation of the TMS-induced CSP in subjects with history of cocaine-dependence that could be due to the effects of cocaine as a dopamine reuptake inhibitor. Increased Source Densities at the Amygdalar and Insular Regions as a Core Finding in Panic Disorder, Clinical Diversity and Possible Physiopathogenic ImplicationsGerez M, Sada A, Serrano C, Castanedo L, Nicolini H, Tello A, Hospital Español de México, Mexico The relationship of panic disorder and complex partial seizures has been suggested and controverted for a long time without a definite understanding of the underlying mechanisms. Despite clinical similarities, the lack of EEG correlates during the attacks, the preservation of consciousness and the variable response to antiepileptics argue against a relationship. Yet, response is variable for other treatment strategies as well, and many partial seizures are also elusive to the surface EEG. In a previous study we reported regional differences in LORETA source density abnormalities among anxiety disorders. Here, we want to extend the findings of increased densities at the amygdalar region in panic disorder by presenting evidence of the same regions affected in most subjects from our sample during asymptomatic recordings, with further increases in four of them during a panic attack, and regional shifts paralleling clinical changes during an ongoing complex seizure in two other patients. Physiopathogenic hypothesis will be presented relating our findings to the fear-learning and the amygdalar kindling models, as well as the modulatory role of serotonin afferents upon the amygdalar target regions. A Topography of Anxiety? Distinct Maps for Different Disorders Gerez, M, Serrano C, Castanedo L, Tello A, Hospital Español de México, México Panic (PD), phobic (PHD), obsessive-compulsive (OCD) and generalized anxiety disorders (GAD) are considered discrete entities under current psychiatric classifications. Yet, comorbidity and similar pharmacologic response argue for common mechanisms. Biological evidence can be found in both directions. We present EEG evidence of brain dysfunction, with some similarities and clear differences among the anxiety disporders (AD). from a sample of 192 unmedicated patients and 30 controls. At visual inspection epileptiform activity was seen in 38 patients, unrelated to diagnosis, but not in controls. Independent split sample discriminant analysis was conducted on a set of QEEG and LORETA variables, selected from previously conducted independent ANOVAs, yielding 87% accuracy individual classification. Decreased delta power was common to all patient groups, stronger in OCD and GAD. LORETA source density increases at particular regions of interest (ROIs) were strongly related to diagnostic group: orbitofrontal to OCD, amygdala and anterior insula to panic, anterior cingulate to GAD and OCD. Our findings support brain dysfunction in anxiety disorders, with a shared component possibly as a final pathway modulated by serotonin, and another, different among disorders with clear regional involvement in OCD and PAN. A Pilot Study Investigating Temporal Lobe Epilepsy as a Possible Etiology of Panic Attacks Gill T, Turner J, Wallace S, Derrick M, Dengler E, Vyas U, Moore N, East Tennessee State University, Johnson City, Tennessee, USA Panic attacks and Temporal Lobe Epilepsy have many of the same clinical signs; some panic attacks may actually be simple partial seizures. If this is the case, antiepileptic drugs may be a more effective treatment for these panic attacks than the SSRIs, TCAs, and benzodiazepines used to treat panic disorder (PD). The goals of this pilot study were to 1) detect epileptic EEG abnormalities in PD patients and 2) assess the feasibility of a full scale study. Seven PD patients and 4 controls were monitored for 24 hours by ambulatory EEG. An investigator, blinded to the PD/control status of patients, evaluated the EEGs for signs of epileptic abnormalities. One control showed normal EEG activity, while the other 3 exhibited suspected epileptic abnormalities. Only 2 PD subjects had EEG findings suggestive of epileptic activity, and both reported at least 1 panic attack during the recording. The other 5 PD subjects, 3 reporting a panic attack, had normal EEG findings. In conclusion, we found no significant difference in EEG findings between the control group and the PD group. Future studies should be of patients with 1 or more panic attacks per day, so that EEG is recorded during an attack. Estimation of Brain Areas Involved in Visual Gating by eLORETA: Preliminary ResultsGjini K, Boutros NN, Wayne State University School of Medicine, Detroit, Michigan, USA Sensory gating in the human brain has been extensively studied in the auditory modality. Recently we have shown gating of visual information by using a paired-flash paradigm (S1-S2). Here we aimed to estimate cortical areas that are involved in gating of irrelevant repeating visual information in the human brain. Eight healthy controls participated in the study. EEG data were collected from 19 scalp sites. eLORETA was used to obtain distributed current estimates of brain activity during S1 and S2 visual stimuli processing from time-domain (P1-N1 evoked potentials) and frequency-domain data (theta band). Additionally, cortical areas involved in gating of the irrelevant visual information were estimated by a statistical comparison of S1 and S2 distributed current distributions in the brain. Initially, gating of irrelevant visual input was shown to take place in occipital cortices and right posterior temporal and premotor cortices (P1-phase). During a later phase (N1-response), gating related activity in anterior cingulated gyrus (ACC) was shown. Similarly in frequency-domain, suppression of theta power was localized in occipital areas and ACC region. These preliminary results should be extended by studying the functional interaction between the involved sources. Utilizing denser EEG array data in the near future would improve the accuracy of our estimates. Acute Medication Challenge Leading to Interhemispheric Coherence Changes in Patients with ADHD Hauser ME, Smithson WA, Poprawski TJ, Paciora RA, Konopka LM, First Chicago Neuroscience, Chicago, Illinios, USA Our objective was to evaluate the effect of acute electrophysiological challenge and subsequent qEEG pattern changes, focusing on coherence in patients with ADHD. This study evaluated 23 self-referred patients (12 males and 11 females), ranging from 12-66 years of age (11 adults and 12 children). Data were collapsed across age since no age effects were observed. Patients with ADHD symptomology were studied using acute oral medication challenge; agent used was Adderall or Ritalin (10-20mg). As described by Konopka and Poprawski (2008), participant brain electrophysiology was evaluated with qEEG at baseline and post-medication. Patients were defined as positive medication responders (n=11) if they improved on electrophysiological patterns based on absolute power. Coherence changes in positive Ritalin (n = 5) and Adderall (n = 6) responders were analyzed using NeuroGuide 2.4.4. Different patterns of electrophysiological coherence were identified based on medication choice, Adderall or Ritalin. In the Adderall medication condition, frontal interhemispheric coherence was significantly improved in alpha frequencies at F3-F4 (p = 0.018). In the Ritalin condition, significant findings were in temporal beta frequencies at T3-T4 (p = 0.016) and in occipital theta frequencies at O1-O2 (p = 0.033). qEEG Findings in Patients with Asthma and Psychiatric Disorders: Use of Antiasthma Medications Hauser ME, Bajo S, Smithson WA, Poprawski TJ, Paciora RA, Konopka LM, First Chicago Neuroscience, Chicago, Illinois, USA Our objective was to evaluate the effect of respiratory illness on quantitative EEG (qEEG) patterns in patients with psychiatric disorders. Interhemispheric coherence differences were identified: parietal interhemispheric coherence findings in alpha and beta (p < 0.05) and right intrahemispheric findings in beta at F4-T4, F4-T6, C4-T4 (p < 0.05). Differences in relative power were also seen in the left occipital region (p < 0.05) and the absolute power showed a trend. The study showed significant qEEG abnormalities in patients with asthma differing with medication usage. These findings provide evidence for focal coherence, absolute and relative power abnormalities potentially related to asthma medication use. Scalp Lateralization of Perisaccadic Gamma Modulation Depends on Saccade DirectionJavaid M, Mohsin H, Glazman S, Flom P, Bodis-Wollner I, SUNY Downstate Med Center, Brooklyn, New York, USA We quantified the hemispheric lateralization of gMI, the index of perisaccadic phasic modulation of the gamma (35–45 Hz ) and beta (18-24 Hz) range EEG in humans. EEG was recorded over the frontal, parietal, temporal and occipital sites in 8 male volunteers (age 23-30 years). Eye movements were recorded with EOG and ISCAN camera. Subjects executed saccades to a mark at right and back to fixation point and vice versa. Two minutes of EEG were obtained from each subject for each of the eight possible saccades (rightwards and leftwards, centripetal and centrifugal x 2 distances). Each perisaccadic EEG segment was analyzed using continuous wavelet transform for quantifying the power and time course of gamma and beta (18–24 Hz.) EEG ranges for each saccade type. General linear mixed model was used for statistical analysis. Perisaccadic gMI (peak intrasaccadic power divided by mean power.) – GMI – is higher over the contralateral hemisphere to the saccade direction, for both centrifugal and centripetal saccades at anterior (p< 0.0050) posterior ( p<0.0106) and occipital (p<0.0106).GMI is higher for centripetal than for centrifugal saccades. There was no evidence of persisaccadic phasic modulation in the beta range. Supported:NPF Standard EEG Study of Acute Psychiatric Patients With Difficult to Assess Mental StatusJavanbakht A, Sadri AA, Ajluni V, Boutros NN, Wayne State University, School of Medicine, Detroit, Michigan, USA Delirium is common on the differential diagnostic list of psychiatric patients in acute care settings. When a patient is unable or unwilling to answer questions about orientation, such determination of possible delirium or other probable etiologies becomes difficult. The role of the standard EEG (SEEG) in evaluating such patients is not known. Subjects were patients whose orientation to time, place, or person could not be assessed by two physicians in the psychiatric crisis center of Detroit Receiving Hospital, Wayne State University. If the patients were clearly disoriented, they were ruled out and the study was done on patients whose orientation was not accessible, i.e., mute patients or patients who would give irrelevant answers. For each subject, 16 channel EEG was performed. From 16 subjects enrolled, 2 had EEGs dominated by theta activity (i.e., slower than 8 Hz). 9 patients had borderline EEG backgrounds with activity mainly in the 8-9 Hz, and 4 were considered normal with activity consistently above 9 Hz. While two of the subjects had clear slowing of the EEG, the majority of them (9 subjects) had borderline background activity mainly in the 8-9 Hz range. These results suggest the need for a more extensive study of a bigger sample group and suggest more careful assessment of psychiatric emergency patients for general medical conditions especially encephalopathy. Event Related Potentials in Response to Significant FacesOfek E, University of Zurich, Switzerland Previous EEG (ERP) studies focused mainly on the physical attributes of the stimulus, and not on the inherent subjective meaning that the stimulus carries. Here, we study the effect of subjective emotional significance of faces on the brain response to them. In a previous study (Ofek and Pratt 2005) we have studied the effect of subjective significance of first names on ERP. Electric brain activity was recorded using 128 EEG channels in 20 healthy subjects in response to 18 faces (facial pictures, brought by the subjects) – familiar, unfamiliar, targets, as well as the subject’s partner and the subject’s own face. Each face was shown for 1250ms, with 750ms green screen between faces, and 500ms cross before each face. The faces were portrait pictures, on a green background. Event related potentials were analyzed for each face, latency 0 till 1000ms. ERP peaks were marked. Distinct event related brain potentials (P3 and LPC) were found for familiar and unfamiliar faces, partner and self, especially in the right parietal scalp distribution. It is possible to discriminate between facial pictures of different subjects, based on the subjective significance that the person carries to the subject, using evoked potentials. Panic Attacks Turning into Complex Seizures: Report of Two CasesSada A, Gerez M, Hospital Español de Mexico, Mexico The phenomenology of panic attacks and complex partial seizures overlap, and at times are difficult to differenciate. Both are paroxysmal, brief and recurrent. In addition, atypical panic attacks also include somatic features such as focal parestesias or sensory distortions. Yet, attempts to demonstrate a relationship or an independence have been unsuccessful. The importance of a differential diagnosis to differentiate between these entities is their very different treatment implications., so we report two cases with typical panic attacks, which, during EEG activating maniouvers, developed complex symptoms paired to changing electrographic patterns up to the installation of a sustained ictal discharge. In both cases, symptoms had been ameliorated by selective serotonine reuptake inhibitors but only disappeared after the addition of anticonvulsants. The two recorded seizures shared some of the source density abnormal locations: amydala and insula during fear feelings with autonomic changes, anterior cingulate, ventral prefrontal, insular, parietal during the ictal discharges. These findings support the hypothesis of an increased basal activation of limbic structures, predominantly amygdala and insula, in PD. More dynamical changes at frontoventral and parahippocampal regions may be related to extended symptoms. They suggest that a regulatory dysfunction at any key site in this network could lead to the development of panic symptoms. QEEGs Diagnostic Effectiveness When Testing for Alzheimer’s DiseaseShetty N, Arfken CL, Boutros N, Wayne State University, Detroit Michigan, USA Diagnosis of Alzheimer’s Disease (AD) would be improved with laboratory tests, like Q-EEG. However, diagnostic effectiveness requires certain parameters; summarized by the 4-step approach. Publications with Q-EEG measurements in AD patients and healthy controls were sought using a PubMed search via key terms “Q-EEG”, “Alzheimer’s”, and “Spectral EEG”(Limits: English and Human). Review articles were also examined for publications. The search “Spectral EEG and Alzheimer’s” resulted in 89 articles, 86 were excluded. “Q-EEG and Alzheimer’s” yielded 52 articles, 49 were excluded. An additional 5 articles were located using searches of the terms individually. All 11 articles qualified for Step 1; 4 articles qualified for Step 2. Only 1 article qualified for step 3. Zero articles qualified for step 4. Q-EEG data were rarely reported. Inclusion criteria: AD group, healthy control, all with reports of actual Q-EEG data with statistics. Q-EEG as a diagnostic test for AD isn’t ready due to lack of step 3 and 4 data. Thus diagnostically, Q-EEGs, although replicable, need to be strengthened with studies consistent with step 3 and 4 processes. Correlations Among Drug Serum Levels, EEG Parameters and Clinical Outcome Tarhan N, Hizli G, Nuhoglu S, NeuroPsychiatry Hospital Istanbul It has been claimed that EEG parameters have a predictive value about the clinical outcome. However, there are contradictory reports. We hypothesized that the reason for the contradictory findings is that they did not take the drug serum levels into account. On the basis of the hypothesis, in this study, correlations among drug serum levels, EEG parameters and clinical outcome measures are investigated. We found that there was significant decrease in theta activity at the first hour EEG after single dose of sertralin 50 mg ingestion. A significant alpha decrease after 7 days of sertralin 50 mg/day oral antidepressant treatment and beta activity decrease after 4 weeks of sertralin 50 mg/day oral treatment were observed on EEG measures. There found to be a highly significant correlation between sertralin plasma levels and theta and alpha activity decrease on EEG records after 2 hours of single dose of 50 mg oral sertralin ingestion. According to the Hamilton Depression Scale, all of the subjects were therapy responder. These findings support that the use of EEG measures have the value of predicting treatment outcome in depression when correlated with the serum drug levels. Fully Automated ICA-Based EEG Blink Artifact Removal Yen Y-T, Sacks AE, Cho RY, University of Pittsburgh, Pittsburgh, Pennsylvania, USA Eye blinks are a prominent artifact in EEG data analysis. Between the two common methods for removing eye blinks from EEG data, independent components analysis (ICA) methods confers possible advantages over the traditional Gratton regression based method. However, ICA methods can be time consuming and cumbersome for the user. Here, we present a fast, automated approach for ICA blink component selection that is consistent and accurate. Blink trials are selected on the basis of their high kurtosis values and followed by exclusion of non-ideal blink trials through use of a peak-finding algorithm and appropriate thresholding. ICA blink components are similarly selected on the basis of high kurtosis values. Then, correlations between candidate ICA blink components and the original EEG blink trials were used to make a final selection of ICA blink components. In conclusion, our automatic ICA blink component detection method is a robust and efficient approach for removing eye blink artifacts from EEG data. Music Therapy in Schizophrenic PopulationYoshida S, Wayne State University, School of Medicine, Detroit, Michigan, USA Schizophrenia is a devastating chronic life-long mental disorder affecting about 1% of the population in the US. Although there is a wide variety of traditional medication available to treat the symptoms of schizophrenia, researchers and clinicians have been exploring nontraditional approaches in addition to the standard medications to improve the quality of patients’ lives. More specifically, this review article will discuss and compare the effectiveness of music therapy in schizophrenic population. A total of 85 and 145 articles were found from databases “pubmed” and “PsycInfo” respectively, with key words including “music therapy” and “schizophrenia”. Thirteen articles, years ranging from 1975 to 2008, were selected for this review. The reasons for eliminations of articles included: non-English language, irrelevancy, and publication types (e.g., reviews, comments, and case studies). Although there are variations in types of measures used to assess the changes due to music therapy, all 13 articles stated positive outcomes. Specifically, several articles concluded that there is a significant decrease in negative symptoms of schizophrenia as well as improvement in psychosocial behaviors (e.g., increased ability to converse with others, reduced social isolation). Since music therapy attenuates asymmetry of frontal EEG in depressed patients, future EEG research using schizophrenic population in conjunction with music therapy is recommended. |
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