Presenta on of the Psychology and Neurofeedback Special Interest Group of the Australian Psychological Society by Professor Richard Clark

Transcription

1 Quantitative EEG and neurofeedback therapy in the assessment and treatment of psychological disorders C. Richard Clark BA (Hons) PhD, MACS, BCN, FASSA Joint Clinical Director, Brain Health Clinics, Adelaide, Australia Professor, School of Psychology, Flinders University, Adelaide, Australia Outline Brain dynamics, conscious versus preconscious informaon processing, and relaonship to neurofeedback therapy EEG and brain funcon EEG markers of aenon and learning difficules - examples Quantave EEG (QEEG) in the assessment of psychological disorders and an ADHD case example Procedures and mechanisms of neurofeedback therapy Professional Development and Naonal Cerficaon in the theory and pracce of neurofeedback 1

2 Brain dynamics, preconscious informaon processing, psychological funcon and their relaonship to neurofeedback therapy Treatment modalies affecng brain and psychological funcon Medicaon: modulaon of global neurotransmier systems acvity Psychological and behavioural therapies: reshaping conscious content and behaviour; language, imagery, feelings QEEG/Neurotherapy: assessing and normalising the preconscious, systemic brain electrical acvity required to establish and maintain conscious working memory funcon Synergies can be obtained with mul- modal approaches 2

3 Preconscious processing extends over ~400ms and involves mulple interacng systems Sensory sampling: A repeated sampling (~10Hz) and processing to cognion of sensory events (thalamocorcal system) Valency and feelings: Parallel evaluaon of the valency of such events; generaon of related feelings (limbic system) Acvaon: direcon of aenon to distributed corcal representaons/associaons of valent event (limbic system; brain stem) Working memory binding: Binding of selected representaons as adapve working memory networks precursor to conscious awareness and mental operaons Systemic dysregulaon impacts on quality and content of conscious funcon but not directly accessible by conscious funcon PARALLEL, HEIRARCHICAL AND DISTRIBUTED PROCESSING 1y/2y Mulmodal Corcal hubs PHASE BOUND WORKING MEMORY ACTIVATIONS Lateral Midline THETA RHYTHMS (3-7 Hz) GAMMA RHYTHMS ( HZ) * BETA (14-24 HZ) ALPHA (8-13HZ) Release of recular inhibion allows material thru to cortex; alpha desynchronises 5. VASCULO- GLIAL SLOW WAVES ACC Synchronised septo- hippocampal bursts Corcal/ subcorcal inputs 3. INTRACORTICAL N. RETICULARIS NEOCORTEX Thalamocorcal bursts seen as alpha rhythms Lateral Inhibion by NRT from causes synchronised thalamocorcal bursts 1. LIMBIC/SEPTO- HIPPOCAMPAL SYSTEM 2. THALAMO- CORTICAL Limbic inputs influence selecon of thalamic material for cortex MOTOR SENSORY Activity of these systems characterised by distinctive spatial and temporal rhythms seen in the EEG 4. BRAINSTEM SLOW WAVE ACTIVATION Increased brainstem monoamines decrease NRT inhibion 3

4 Thalamocortical system Cognitive representation of world cortex as global workspace - DELTA (1-4 HZ), ALPHA (8-13 HZ) BETA (14-25 HZ) INTRA- CORTICAL GAMMA ( HZ) Prefrontal Execuve PMC Preparaon Brocas Speech Motor Acon Somatosensory Body IPL Conceptual Auditory Sound Temporal Conceptual SPL Spaal Wernicke Language V5 Moon VI- 4 Visual Mulmodal convergence zones.. group of interconnected corcal and subcorcal structures dedicated to linking visceral states and emoon to cognion and behaviour (Mesulam, 2000). Cingulate cortex Medial Fornix Thalamus 3D perspecve Paracentral lobule Frontal pole Olfactory bulb Superior frontal Ant. CC Medial Orbito- frontal Septum Amygdala Mid CC Entorhinal Insula Hippocampus Post. CC Parahippocampal Retro Splenial Mamillary bodies Limbic- cortical system Affective processing of world Pre- cuneus Cuneus Salience assessed via viscerosensory analysis of dorsal and anterior insula. Idenfies acvaons for control of aenon to lateral corcal fields via cingulate systems Neural correlate: Theta rhythm (3-7 Hz) (Sensory event - > emoon - > viscerosensaon - > salience - > feelings/aenon - > episodic memory) 4

5 INFRASLOW ( HZ) AND SLOW ( HZ) CORTICAL POTENTIALS (Glutamate) Glia, blood- epithelial interface Metabolism, O 2, Glucose.. (??) MONOAMINES HZ LC (Noradrenaline) Alerng, vigilance SN/VTA (Dopamine) Movement Movaon/Explicit learning Raphe (Serotonin) Movaon/Implicit learning Basal forebrain (Ach) Aenon Brainstem ARAS (Ach, Glu) Arousal Lat. Hypothalamus (Orexin) Supermodulaon, wakefulness Tuberomamm. N. (Histamine) Sleep- wake cycle Adapted from THE MIND S MACHINE, FIG 4 Sinauer Associates Inc Modulation of brain activity Energetics; regional/systemic arousal and activation Radial Thalamocortical Corticolimbic Fast and speciic Limited domain Information transfer Interneuron, (lateral inhibion etc.) GABA (- ), Pepdes Vasculo- glial modulaon Thalamocorcal Glutamate (+), Aspartate (+) Limbic- corcal Glutamate (+), Aspartate (+) Corcocorcal Glutamate (+), Aspartate (+) Sensory, semantic, conceptual Tangential Monoaminergic Slow, non- speciic Large domain Modulatory FUNCTIONAL CONVERGENCE OF SYSTEMS DETERMINE LOCAL CONTRIBUTION TO REPRESENTATIONAL PATTERNS Local acvaon determined by convergent interacon of these systems Underlies convergent processes of (a) regional priming & acvaon (SCP; lateral inhibion) (b) cognive elaboraon (Alpha1, 2) (c) affecve biasing (Theta) and (c) phase- locked, working memory acvaon (Gamma) of salient informaon leading to awareness Brainstem and basal forebrain modulatory afferents Dopamine, Noradrenaline, Serotonin, Histamine, Acetylcholine Moment to moment seeking of regional mimina 5

6 Brain electrical fields & preconscious processes Breakdown in these preconscious processes affects conscious awareness Such dysregulaon not directly accessible to conscious awareness Examples of psychological condions involving such dysregulaon: Developmental disorders e.g. ADHD, ASD, language disorders, cs; Anxiety disorders (GAD, Panic disorder); Trauma and stress disorders; OCD; Depressive disorders Neurotherapy works on dysfuncon through modulaon of related brain electrical fields Example Evoluon of brain electrical field acvity associated with processing a simple smulus event Resulng in standing fields reflecng distributed working memory Here seen bilaterally over temporal, parietal and frontal regions; and centrally over cingulate regions 400ms post- event EEG and brain funcon 6

7 EEG relects brain electrical ield activity SCALP NEOCORTICAL LAMINAE EEG reflects the electrical component of the open fields of corcal pyramidal cells; organised in noonal columns Pyramidal neurons most numerous in cortex (>100,000 million) Electrical fields capture degree of synchronisaon of underlying acvity (~1cm radius, ~50 million pyramidal cells) & reveals the oscillatory rhythms of the brain or EEG Brain electrical ield activity and the EEG Electrode cap Amplifier and computer EEG measured using sensing electrodes (1 to 256) placed on scalp; usually 19 channels. Scalp impedence preparaon necessary Electrode gels generally used to facilitate signal capture Signals amplified, digised (~ samples/sec) and preprocessed to allow visualisaon & analysis 7

8 EEG display demonstrating temporal and site variability in oscillatory frequency & power, relecting composite neurological activity Awake Slow and infraslow Vasculoglial, Modulatory, brain SCPs stem SCPs Thal- Ctx disconnecon Limbic- Ctx affecve Thal- Ctx Relaxed but Resng alert alert Amplitude and frequency characteriscs of the EEG Thal- Ctx Motor alert Ctx cognive Mental Ctx work (acve mental LCPs) processes Adapted from Sherlin,

9 Examples of EEG indicators of aenon and learning difficules Normal EEG of awake alert state Abnormal Thal- Ctx alpha Excessive posterior alpha acvity reflecng abnormal thalamocorcal funcon underacvaon affecng sensory integraon, sensory aenon and related learning 9

10 Abnormal midline limbic theta resulting in attentional dysregulation theta-beta subtype Excess theta (limbic corcal network) and reducons in beta (intracorcal dysregulaon) in >50% of ADHD: evaluaon issues Intracortical overactivation resulting in attentional dysregulation beta spindling subtype : EC; 7 yrs. Inattentive problems. Widespread spindling High beta spindling related to pre- epilepc auras, epilepsy, corcal irritaon and some forms of encephalopathy. 10

11 Quantave EEG in the assessment of psychological disorders Quantave EEG (qeeg) quanfies power, frequency and phase of electrical field oscillaons 11

12 Quantifying & parameterising spectral frequencies in the EEG Measures of test- retest and split half reliability Power Spectral plot Absolute Power by resonance band (Frequency: 1-30Hz) Resonant frequency SD Normality across resonance bands (z- score) Resonant frequency Quantifying & parameterising spectral frequencies in the EEG Power Absolute Power by resonance band (Frequency: 1-30Hz) Z- score Measure of normality across resonant frequency power (z- score) 2sd Resonant frequency Resonant frequency 12

13 ADHD case example QEEG assessment Male teenager Case CRC112 CRC112 Power SPECTRAL POWER Theta excess (5HZ) Z- score SPECTRAL STATS Theta bursts over midfrontal regions Stascal outliers (>4sd) at 5Hz - Limbic 2sd threshold EEG traces, spectral values and spectral statistics relative to age matched normative database Frequency CRC112 13

14 Peak acvaon Localised bilaterally to Brodmann areas 24, 32 and 33 of anterior and middle cingulate gyri associated with affecve and aenonal regulaon, and impacng on frontal and parietotemporal recruitment, respecvely Z scores All slices Image source: Hoffstaedter et al 2014 Brain mapping of statistical abnormality using 3D source localisation (LORETA) CRC112 Pre- treatment Post- treatment STEN SD Pre- treatment Post- treatment - - PRE- POST ANALYSIS ADHD CASE CRC112 14

15 Neurofeedback therapy Neurofeedback therapy Operant training mediated by feedback of targeted brain acvity over mulple sessions Complex form of behavioural therapy, with posive and negave feedback determined by related valency of targeted brain acvity Electrodes AV feedback Operant training curve for neurofeedback gains Asymptote, consolidaon Improvement Fast acquision stage Slow early changes Amplifier Treatment sessions Neurofeedback generally involves sensory (auditory, visual, tactile) feedback based on real- time analysis of targeted brain function 15

16 More Computed acvity of targeted system based on raw measures such as power, phase or coherence 19 channel EEG training may use selected EEG components from one or more sites Power Phase Coherence Negave reinforcement provided Posive reinforcement provided REWARD Z- score TRAINING REINFORCEMENT THRESHOLD + 0 Computed acvity of targeted system based on proximity to stascal norm Less Time _ Neurofeedback reinforcement process Realme derivaon from 19 channel EEG of composite training metric, based on acvity of system target(s) from QEEG analysis. Training proceeds either in terms of metric or z- score transform based on reference norms Neural mechanisms underlying reinforcement learning (see Kandel et al, 2012, Principles of Neural Science) 16

17 Neurofeedback therapy Single or mulple sites on scalp Training of scalp or source rhythms Passive (sub- conscious brain acvity) or acve (slow corcal potenals related to acve aenon) AV feedback Electrodes Amplifier Neurofeedback generally involves sensory (auditory, visual, tactile) feedback based on real- time analysis of targeted brain function Neurofeedback therapy Many hardware systems e.g. Mitsar, EEGer, Neuroscan, Lexicor, Q20, PET Many soware systems e.g. EEGer, Neuroguide, Bioexplorer, Thought Technology AV feedback Electrodes Amplifier Neurofeedback generally involves sensory (auditory, visual, tactile) feedback based on real- time analysis of targeted brain function 17

18 Extract of a sample neurofeedback session here using z- score training of source activity End of presentation 18