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Cao C, Slobounov S. Application of a novel measure of EEG non-stationarity as 'Shannon- entropy of the peak frequency shifting' for detecting residual abnormalities in concussed individuals. Clin Neurophysiol 2011; 122:1314-21. [PMID: 21216191 PMCID: PMC3105191 DOI: 10.1016/j.clinph.2010.12.042] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2010] [Revised: 12/04/2010] [Accepted: 12/07/2010] [Indexed: 10/18/2022]
Abstract
OBJECTIVE The aim of this report was to propose a novel measure of non-stationarity of EEG signals, named Shannon- entropy of the peak frequency shifting (SEPFS). The feasibility of this method was documented comparing this measure with traditional time domain assessment of non-stationarity and its application to EEG data sets obtained from student-athletes before and after suffering a single episode of mild traumatic brain injury (mTBI) with age-matched normal controls. METHODS Instead of assessing the power density distribution on the time-frequency plane, like previously proposed measures of signal non-stationarity, this new measure is based on the shift of the dominant frequency of the EEG signal over time. We applied SEPFS measure to assess the properties of EEG non-stationarity in subjects before and shortly after they suffered mTBI. Student-athletes at high risk for mTBI (n=265) were tested prior to concussive episodes as a baseline. From this subject pool, 30 athletes who suffered from mTBI were retested on day 30 post-injury. Additional subjects pool (student-athletes without history of concussion, n=30) were recruited and test-re-tested within the same 30 day interval. Thirty-two channels EEG signals were acquired in sitting eyes closed condition. RESULTS The results showed that the SEPFS values significantly decreased in subjects suffering from mTBI. Specifically, reduced EEG non-stationarity was observed in occipital, temporal and central brain areas, indicating the possibility of residual brain dysfunctions in concussed individuals. A similar but less statistically significant trend was observed using traditional time domain analysis of EEG non-stationarity. CONCLUSIONS The proposed measure has at least two merits of interest: (1) it is less affected by the limited resolution of time-frequency representation of the EEG signal; (2) it takes into account the neural characteristics of the EEG signal that have not been considered in previously proposed measures of non-stationarity. SIGNIFICANCE This new method may potentially be used as a complementary tool to assess the alteration of brain functions as a result of mTBI.
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Affiliation(s)
- Cheng Cao
- Department of Kinesiology, 19 Recreation Building, The Pennsylvania State University, University Park, PA 16802, USA
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202
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Leiser SC, Dunlop J, Bowlby MR, Devilbiss DM. Aligning strategies for using EEG as a surrogate biomarker: A review of preclinical and clinical research. Biochem Pharmacol 2011; 81:1408-21. [DOI: 10.1016/j.bcp.2010.10.002] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2010] [Revised: 10/01/2010] [Accepted: 10/01/2010] [Indexed: 11/30/2022]
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203
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Doppelmayr M, Weber E. Effects of SMR and Theta/Beta Neurofeedback on Reaction Times, Spatial Abilities, and Creativity. ACTA ACUST UNITED AC 2011. [DOI: 10.1080/10874208.2011.570689] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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204
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Electrophysiological markers of genetic risk for attention deficit hyperactivity disorder. Expert Rev Mol Med 2011; 13:e9. [PMID: 21426626 DOI: 10.1017/s1462399411001797] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Attention deficit hyperactivity disorder (ADHD) is a highly heritable neurodevelopmental disorder with complex genetic aetiology. The identification of candidate intermediate phenotypes may facilitate the detection of susceptibility genes and neurobiological mechanisms underlying the disorder. Electroencephalography (EEG) is an ideal neuroscientific approach, providing a direct measurement of neural activity that demonstrates reliability, developmental stability and high heritability. This systematic review evaluates the utility of a subset of electrophysiological measures as potential intermediate phenotypes for ADHD: quantitative EEG indices of arousal and intraindividual variability, and functional investigations of attention, inhibition and performance monitoring using the event-related potential (ERP) technique. Each measure demonstrates consistent and meaningful associations with ADHD, a degree of genetic overlap with ADHD and potential links to specific genetic variants. Investigations of the genetic and environmental contributions to EEG/ERP and shared genetic overlap with ADHD might enhance molecular genetic studies and provide novel insights into aetiology. Such research will aid in the precise characterisation of the clinical deficits seen in ADHD and guide the development of novel intervention and prevention strategies for those at risk.
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205
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Lansbergen MM, Arns M, van Dongen-Boomsma M, Spronk D, Buitelaar JK. The increase in theta/beta ratio on resting-state EEG in boys with attention-deficit/hyperactivity disorder is mediated by slow alpha peak frequency. Prog Neuropsychopharmacol Biol Psychiatry 2011; 35:47-52. [PMID: 20713113 DOI: 10.1016/j.pnpbp.2010.08.004] [Citation(s) in RCA: 129] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2010] [Revised: 07/21/2010] [Accepted: 08/05/2010] [Indexed: 10/19/2022]
Abstract
Attention-deficit/hyperactivity disorder (ADHD) was found to be characterized by a deviant pattern of electrocortical activity during resting state, particularly increased theta and decreased beta activity. The first objective of the present study is to confirm whether individuals with slow alpha peak frequency contribute to the finding of increased theta activity in ADHD. The second objective is to explore the relation between resting-state brain oscillations and specific cognitive functions. From 49 boys with ADHD and 49 healthy control boys, resting-state EEG during eyes open and eyes closed was recorded, and a variety of cognitive tasks were administered. Theta and beta power and theta/beta ratio were calculated using both fixed frequency bands and individualized frequency bands. As expected, theta/beta ratio, calculated using fixed frequency bands, was significantly higher in ADHD children than control children. However, this group effect was not significant when theta/beta ratio was assessed using individualized frequency bands. No consistent relation was found between resting-state brain oscillations and cognition. The present results suggest that previous findings of increased theta/beta ratio in ADHD may reflect individuals with slow alpha peak frequencies in addition to individuals with true increased theta activity. Therefore, the often reported theta/beta ratio in ADHD can be considered a non-specific measure combining several distinct neurophysiological subgroups such as frontal theta and slowed alpha peak frequencies. Future research should elucidate the functional role of resting-state brain oscillations by investigating neurophysiological subgroups, which may have a clearer relation to cognitive functions than single frequency bands.
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Affiliation(s)
- Marieke M Lansbergen
- Department of Psychiatry, Radboud University Nijmegen Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands.
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206
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Kooij SJJ, Bejerot S, Blackwell A, Caci H, Casas-Brugué M, Carpentier PJ, Edvinsson D, Fayyad J, Foeken K, Fitzgerald M, Gaillac V, Ginsberg Y, Henry C, Krause J, Lensing MB, Manor I, Niederhofer H, Nunes-Filipe C, Ohlmeier MD, Oswald P, Pallanti S, Pehlivanidis A, Ramos-Quiroga JA, Rastam M, Ryffel-Rawak D, Stes S, Asherson P. European consensus statement on diagnosis and treatment of adult ADHD: The European Network Adult ADHD. BMC Psychiatry 2010; 10:67. [PMID: 20815868 PMCID: PMC2942810 DOI: 10.1186/1471-244x-10-67] [Citation(s) in RCA: 505] [Impact Index Per Article: 36.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2010] [Accepted: 09/03/2010] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Attention deficit hyperactivity disorder (ADHD) is among the most common psychiatric disorders of childhood that persists into adulthood in the majority of cases. The evidence on persistence poses several difficulties for adult psychiatry considering the lack of expertise for diagnostic assessment, limited treatment options and patient facilities across Europe. METHODS The European Network Adult ADHD, founded in 2003, aims to increase awareness of this disorder and improve knowledge and patient care for adults with ADHD across Europe. This Consensus Statement is one of the actions taken by the European Network Adult ADHD in order to support the clinician with research evidence and clinical experience from 18 European countries in which ADHD in adults is recognised and treated. RESULTS Besides information on the genetics and neurobiology of ADHD, three major questions are addressed in this statement: (1) What is the clinical picture of ADHD in adults? (2) How can ADHD in adults be properly diagnosed? (3) How should ADHD in adults be effectively treated? CONCLUSIONS ADHD often presents as an impairing lifelong condition in adults, yet it is currently underdiagnosed and treated in many European countries, leading to ineffective treatment and higher costs of illness. Expertise in diagnostic assessment and treatment of ADHD in adults must increase in psychiatry. Instruments for screening and diagnosis of ADHD in adults are available and appropriate treatments exist, although more research is needed in this age group.
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Affiliation(s)
- Sandra JJ Kooij
- PsyQ, psycho medische programma's, Department Adult ADHD, Carel Reinierszkade 197, Den Haag, The Netherlands
| | - Susanne Bejerot
- Department of Clinical Neuroscience, Karolinksa Institutet, Section Psychiatry, St. Goran, Stockholm, Sweden
| | - Andrew Blackwell
- University Department of Psychiatry, Addenbrookes Hospital, Cambridge, UK
| | - Herve Caci
- Pediatric Department, Hôpitaux Pédiatriques CHU-Lenval, 06200 Nice, France
| | - Miquel Casas-Brugué
- Servicio de Psiquiatria, Hospital Universitari Vall d' Hebron, Universidad Autonoma de Barcelona, Barcelona, Spain
| | - Pieter J Carpentier
- Reinier van Arkel Groep, Postbus 70058, 5201 DZ 's-Hertogenbosch, The Netherlands
| | - Dan Edvinsson
- Department of Neuroscience/Psychiatri Ulleråker, MK 75, S-750 17 Uppsala, Sweden
| | - John Fayyad
- Institute of Development, Research, Advocacy and Applied Care (IDRAAC), Department of Psychiatry and Clinical Psychology, St George Hospital University Medical Centre, Balamand University, Beirut, Lebanon
| | - Karin Foeken
- Centre des Consultations, Institut A Tzanck, Mougins, France
| | - Michael Fitzgerald
- Department of Psychiatry, Trinity College Dublin (TCD), Dublin 2, Ireland
| | - Veronique Gaillac
- Clinique des Maladies Mentales et de l'Encéphale (CMME), Sainte Anne Hospital Paris, France
| | - Ylva Ginsberg
- Affektiva mottagningen, M 59, Psykiatri Sydväst, 141 86 Stockholm, Sweden
| | - Chantal Henry
- Département de Psychiatrie Adulte, Unité Lescure, CH Charles Perrens, Bordeaux, France
| | - Johanna Krause
- Private clinic for psychiatry and psychotherapy, 11a Schillerstrasse, Ottobrunn, Germany
| | - Michael B Lensing
- Department of Child Neurology, Oslo University Hospital, Ullevaal, Oslo, Norway
| | - Iris Manor
- Geha Mental Health Center, Petach-Tiqva, Sackler Faculty of Medicine, Tel-Aviv University, Israel
| | - Helmut Niederhofer
- Department of Child Psychiatry, Regional Hospital of Bolzano, Via Guncina, Bolzano, Italy
| | - Carlos Nunes-Filipe
- Faculty of Medical Sciences, New University of Lisbon, Campo dos Mártires da Pátria, 1169-056 Lisboa, Portugal
| | - Martin D Ohlmeier
- Department of Psychiatry, Social Psychiatry and Psychotherapy, Hannover Medical School, Germany
| | - Pierre Oswald
- Department of Psychiatry, Brugmann University Hospital, Université Libre de Bruxelles, Brussels, Belgium
| | - Stefano Pallanti
- Department of Neurosciences, Florence University, Florence, Italy
| | - Artemios Pehlivanidis
- Department of Psychiatry, National and Kapodistrian University of Athens Medical School, Eginition Hospital, Athens, Greece
| | - Josep A Ramos-Quiroga
- Programa Integral del Déficit de Atención en el Adulto (P.I.D.A.A), Servei de Psiquiatria, Hospital Universitari Vall d'Hebron, Barcelona, Spain
| | - Maria Rastam
- Department of Clinical Sciences, Lund, Child and Adolescent Psychiatry, Lund University, Sweden
| | | | - Steven Stes
- ADHD Program, University Psychiatric Center, Catholic University Leuven, Kortenberg, Belgium
| | - Philip Asherson
- MRC Social Genetic and Developmental Psychiatry, Institute of Psychiatry, Kings College London, London, UK
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207
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Perreau-Linck E, Lessard N, Lévesque J, Beauregard M. Effects of Neurofeedback Training on Inhibitory Capacities in ADHD Children: A Single-Blind, Randomized, Placebo-Controlled Study. ACTA ACUST UNITED AC 2010. [DOI: 10.1080/10874208.2010.501514] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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208
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Affiliation(s)
| | - Patricia Boksa
- Correspondence to: Dr. P. Boksa, Douglas Institute — Research, Pavilion Perry, Rm. E-2110, 6875 LaSalle Blvd., Verdun QC H4H 1R3; fax 514 762-3034;
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209
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Kanda PADM, Anghinah R, Smidth MT, Silva JM. The clinical use of quantitative EEG in cognitive disorders. Dement Neuropsychol 2009; 3:195-203. [PMID: 29213628 PMCID: PMC5618973 DOI: 10.1590/s1980-57642009dn30300004] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The primary diagnosis of most cognitive disorders is clinically based, but the
EEG plays a role in evaluating, classifying and following some of these
disorders. There is an ongoing debate over routine use of qEEG. Although many
findings regarding the clinical use of quantitative EEG are awaiting validation
by independent investigators while confirmatory clinical follow-up studies are
also needed, qEEG can be cautiously used by a skilled neurophysiologist in
cognitive dysfunctions to improve the analysis of background activity, slow/fast
focal activity, subtle asymmetries, spikes and waves, as well as in longitudinal
follow-ups.
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Affiliation(s)
- Paulo Afonso de Medeiros Kanda
- Reference Center of Behavioral and Cognitive Disorders of Clinicas Hospital of the University of São Paulo School of Medicine, São Paulo, SP, Brazil
| | - Renato Anghinah
- Reference Center of Behavioral and Cognitive Disorders of Clinicas Hospital of the University of São Paulo School of Medicine, São Paulo, SP, Brazil
| | - Magali Taino Smidth
- Reference Center of Behavioral and Cognitive Disorders of Clinicas Hospital of the University of São Paulo School of Medicine, São Paulo, SP, Brazil
| | - Jorge Mario Silva
- Reference Center of Behavioral and Cognitive Disorders of Clinicas Hospital of the University of São Paulo School of Medicine, São Paulo, SP, Brazil
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210
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The cerebellum in emotion regulation: a repetitive transcranial magnetic stimulation study. THE CEREBELLUM 2009; 8:28-34. [PMID: 18855096 DOI: 10.1007/s12311-008-0056-6] [Citation(s) in RCA: 133] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Several lines of evidence suggest that the cerebellum may play a role in the regulation of emotion. The aim of this study was to investigate the hypothesis that inhibition of cerebellar function using slow repetitive transcranial magnetic stimulation (rTMS) would lead to increased negative mood as a result of impaired emotion regulation. In a randomized counterbalanced within-subjects design, 12 healthy young right-handed volunteers received 20 min of cerebellar, occipital, or sham 1 Hz rTMS on three separate days. Mood state inventories were acquired prior to and immediately after rTMS and after an emotion regulation task (ERT). In the ERT, participants were instructed to either look at aversive and neutral scenes, or to suppress the negative feelings experienced while watching aversive scenes during which the electroencephalogram (EEG) was recorded. Results showing no changes in baseline-corrected mood were observed immediately after rTMS. However, significant increases in baseline-corrected negative mood following the ERT were reported after cerebellar rTMS exclusively. No effects on the EEG during the ERT were observed. These findings provide support for the view that the cerebellum is implicated in the regulation of emotion and mood, and concur with evidence of cerebellar abnormalities observed in disorders associated with emotion dysregulation. In order to clarify the underlying biological mechanisms involved, more research is needed.
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211
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Abstract
Quantifying EEG measures across age allows the ability to establish parameters of normalcy at any age which can be used as a reference when children exhibit developmental delays in their abilities and/or other atypical and maladaptive behaviors. A review of the current literature on the utilization of QEEG methods to serve as an aid for identifying these children as distinctively different from normal, and in some cases as distinctive from other clinical considerations has been shown to provide a sufficient sensitivity and specificity worthy of consideration as a diagnostic aid in evaluating clinical deviations in development. Furthermore, these same QEEG measures can provide a means of establishing treatment efficacy for the evident brain dysfunctions underlying these childhood disorders.
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Affiliation(s)
- David S Cantor
- Psychological Sciences Institute, Atlanta, Georgia, USA.
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212
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Monastra VJ. Quantitative electroencephalography and attention-deficit/hyperactivity disorder: implications for clinical practice. Curr Psychiatry Rep 2008; 10:432-8. [PMID: 18803918 DOI: 10.1007/s11920-008-0069-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Although behavioral symptoms of inattention, impulsivity, and hyperactivity serve as a foundation for the accurate diagnosis of attention-deficit/hyperactivity disorder (ADHD), the low interrater reliability and specificity of behavioral rating scales and the absence of comprehensive screening for medical conditions that mimic ADHD have created a barrier to the effective treatment of ADHD. Recently published studies using quantitative electroencephalographic techniques have identified abnormal patterns of cortical activation through power spectral analysis, in event-related cortical potentials, and in slow cortical potentials that may serve as a basis for overcoming these barriers. This paper reviews the initial evidence indicating that power spectral analysis and event-related cortical potentials may be useful in differentiating ADHD from other psychiatric disorders, helping in medication selection, evaluating medication response, and improving the rate of treatment initiation and maintenance. Studies examining electroencephalogram biofeedback (neurotherapy) are reviewed using published efficacy guidelines.
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Affiliation(s)
- Vincent J Monastra
- FPI Attention Disorders Clinic, Department of Psychology, Binghamton University, 94 Marshall Drive, Endicott, NY 13760, USA.
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213
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Snyder SM, Quintana H, Sexson SB, Knott P, Haque AFM, Reynolds DA. Blinded, multi-center validation of EEG and rating scales in identifying ADHD within a clinical sample. Psychiatry Res 2008; 159:346-58. [PMID: 18423617 DOI: 10.1016/j.psychres.2007.05.006] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2006] [Revised: 01/24/2007] [Accepted: 05/09/2007] [Indexed: 11/26/2022]
Abstract
Previous validation studies of attention deficit/hyperactivity disorder (ADHD) assessment by rating scales or EEG have provided Class-IV evidence per standards of the American Academy of Neurology. To investigate clinical applications, we collected Class-I evidence, namely from a blinded, prospective, multi-center study of a representative clinical sample categorized with a clinical standard. Participating males (101) and females (58) aged 6 to 18 had presented to one of four psychiatric and pediatric clinics because of the suspected presence of attention and behavior problems. DSM-IV diagnosis was performed by clinicians assisted with a semi-structured clinical interview. EEG (theta/beta ratio) and ratings scales (Conners Rating Scales-Revised and ADHD Rating Scales-IV) were collected separately in a blinded protocol. ADHD prevalence in the clinical sample was 61%, whereas the remainder had other childhood/adolescent disorders or no diagnosis. Comorbidities were observed in 66% of ADHD patients and included mood, anxiety, disruptive, and learning disorders at rates similar to previous findings. EEG identified ADHD with 87% sensitivity and 94% specificity. Rating scales provided sensitivity of 38-79% and specificity of 13-61%. While parent or teacher identification of ADHD by rating scales was reduced in accuracy when applied to a diverse clinical sample, theta/beta ratio changes remained consistent with the clinician's ADHD diagnosis. Because theta/beta ratio changes do not identify comorbidities or alternative diagnoses, the results do not support the use of EEG as a stand-alone diagnostic and should be limited to the interpretation that EEG may complement a clinical evaluation for ADHD.
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Affiliation(s)
- Steven M Snyder
- Department of Psychology, University of North Texas Health Science Center at Fort Worth, Fort Worth, TX 76107, USA.
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214
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Bush G. Neuroimaging of attention deficit hyperactivity disorder: can new imaging findings be integrated in clinical practice? Child Adolesc Psychiatr Clin N Am 2008; 17:385-404, x. [PMID: 18295152 DOI: 10.1016/j.chc.2007.11.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Recent advances in neuroimaging research have helped elucidate the neurobiology of attention deficit hyperactivity disorder (ADHD) and the mechanisms by which medications used to treat ADHD exert their effects. The complex nature and array of imaging techniques, however, present challenges for the busy clinician in assessing possible clinical uses of brain imaging. Even though currently there are no accepted uses for imaging in diagnosing ADHD (other than ruling out identifiable medical or neurologic conditions that may mimic ADHD), this review introduces the main imaging techniques used to study ADHD, identifies relevant complexities facing psychiatric researchers in implementing neuroimaging techniques for clinical purposes, and provides benchmarks to help determine when imaging modalities have advanced to a point that they are deemed clinically useful.
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Affiliation(s)
- George Bush
- Department of Psychiatry, Harvard Medical School, 25 Shattuck Street, Boston, MA 02115, USA.
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215
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Marco-Pallares J, Cucurell D, Cunillera T, García R, Andrés-Pueyo A, Münte TF, Rodríguez-Fornells A. Human oscillatory activity associated to reward processing in a gambling task. Neuropsychologia 2008; 46:241-8. [PMID: 17804025 DOI: 10.1016/j.neuropsychologia.2007.07.016] [Citation(s) in RCA: 200] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2007] [Revised: 07/18/2007] [Accepted: 07/19/2007] [Indexed: 11/26/2022]
Abstract
Previous event-related brain potential (ERP) studies have identified a medial frontal negativity (MFN) in response to negative feedback or monetary losses. In contrast, no EEG correlates have been identified related to the processing of monetary gains or positive feedback. This result is puzzling considering the large number of brain regions involved in the processing of rewards. In the present study we used a gambling task to investigate this issue with trial-by-trial wavelet-based time-frequency analysis of the electroencephalographic signal recorded non-invasively in healthy humans. Using this analysis a mediofrontal oscillatory component in the beta range was identified which was associated to monetary gains. In addition, standard time-domain ERP analysis showed an MFN for losses that was associated with an increase in theta power in the time-frequency analysis. We propose that the reward-related beta oscillatory activity signifies the functional coupling of distributed brain regions involved in reward processing.
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Affiliation(s)
- Josep Marco-Pallares
- Department of Neuropsychology, Otto von Guericke University, 39112 Magdeburg, Germany
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216
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217
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Subjective impulsivity and baseline EEG in relation to stopping performance. Brain Res 2007; 1148:161-9. [PMID: 17362884 DOI: 10.1016/j.brainres.2007.02.034] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2006] [Revised: 02/10/2007] [Accepted: 02/14/2007] [Indexed: 10/23/2022]
Abstract
Impulsivity is a personality trait within the normal population, but also a feature of many psychiatric disorders that have been associated with poor inhibitory control. The aim of the present study was to examine the relation between subjective impulsivity, theta/beta EEG ratio, and inhibitory control in healthy individuals. In 15 high and 14 low impulsive healthy volunteers (as assessed by the I(7) questionnaire), resting state EEG was recorded during an eyes open condition to obtain estimates for theta and beta activity. Subsequently, a stop-signal task was presented where participants responded to go-signals and had to stop their initiated response to stop-signals. Stopping performance and EEG activity were compared between the impulsive groups as well as between high vs. low theta/beta ratio groups. Results showed that subjective impulsivity was not related to stopping behavior or to theta/beta ratio. In contrast to our expectations that individuals with high theta/beta ratios would show relatively long stopping reaction times, analyses revealed that the low theta/beta ratio group had longer stopping reaction times. Given that increased theta/beta ratio may reflect reduced cortical inhibition over subcortical drives, it is proposed that healthy individuals with relative high theta/beta ratios are more motivated to maximize inhibition-related performance.
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