Evoked in addition to Event-Related Potentials (ERP) Part 1 – Neurophysiological in addition to Anatom

Evoked in addition to Event-Related Potentials (ERP) Part 1 - Neurophysiological in addition to Anatom www.phwiki.com

Evoked in addition to Event-Related Potentials (ERP) Part 1 – Neurophysiological in addition to Anatom

Flatt, Mike, Overnight On-Air Personality has reference to this Academic Journal, PHwiki organized this Journal Evoked in addition to Event-Related Potentials (ERP) Part 1 – Neurophysiological in addition to Anatomical Basis of Scalp-Recorded Activity Craig E. Tenke & Jürgen Kayser Division of Cognitive Neuroscience, New York State Psychiatric Institute, NY, NY Department of Psychiatry, Columbia University College of Physicians & Surgeons, NY, NY towns (Geography: in southern France, Germany, Netherl in addition to s) enterprise resource planning (In as long as mation Technology) Ethernet Ring Protection (In as long as mation Technology) erotic role-playing (Sexuality) Economic Report of the President (Economics) effective refractory period (Medicine: cardiac cycle) Estonian Re as long as m Party (Politics) Electronic Road Pricing (Politics: toll-collection scheme in Singapore) European Recovery Program (History: Marshall Plan) European Radio Project (Communication: European Radio Network) exposure in addition to response prevention (Psychology: cognitive-behavioral treatment method) event-related potential (Physics: an electrophysiological response to an internal or external stimulus) Acronym ERP (wikipedia examples) Event Related Potentials (ERP): Basics (Part 1) 27-Jan-2009 Outline Part 1: Neurophysiological in addition to Anatomical Basis of Scalp-Recorded Activity Introduction: EEG measures synchronized neuronal activity (signal source) The basic scientific method Stimulation – Recording Signal tracing/processing Signal averaging: Evoked potentials (EPs) in addition to event-related potentials (ERPs) Theory of signal averaging Animated examples ERP applications ERP topographies: Indicators of neuroanatomy EEG biophysics Volume Conduction in addition to Ohm’s Law: Point generators Vector as long as mulation: A general model Closed vs. open fields The cortical dipole: Direct evidence A matter of scale: Micro- vs. macro- in addition to intracranial vs. scalp electrodes Part 2: Data acquisition in addition to analysis: Conventions as long as scalp-recorded ERPs (details to be decided) Part 1 Neurophysiological in addition to Anatomical Basis of Scalp-Recorded Activity Evoked in addition to Event-Related Potentials (ERP)

Lawrence Technological University US www.phwiki.com

This Particular University is Related to this Particular Journal

What does EEG measure Changes in the extracellular potential corresponding to membrane polarization Polarity reflects location of cellular activity Equivalent Current Dipole from apical EPSP Equivalent Current Dipole from deep EPSP Desynchronized PSP’s voltages cancel “Closed Field” (No EEG at Scalp) Importance of synchronized activity

Synchronized PSPs voltages add “Open Field” (EEG at scalp) Importance of synchronized activity when local neuronal activity is synchronized (time) when activity produces an open field (space) when activity at the recording site differs from the reference Scalp-recorded EEG is measurable Stimulation-Recording methods use timelocking to synchronize activity

Stimulation-Recording Methods: Tracing signals through a “Black Box” Signal Tracing: Transit time: Response Function: To find System Properties Compare Input Signal With Output Signal e.g. synaptic delay across a sensory nucleus Filtering in addition to gain of output wave as long as m Nonlinear properties (e.g. flicker fusion) Wave as long as m latency, shape in addition to topography e.g. cortical mapping 80 mm from stimulus Threshold Intensity Differential Threshold Differential Velocity up is negative; right is reference Mann 1997 Erlanger & Gasser Compound Action Potential: A Stimulation-Recording Archetype time-locked electrical response of a neural system to an electrical or sensory signal Averaged Evoked Potential Evoked Potential (EP) Sch in addition to ry 1989 average of time-locked EPs EPs may vary considerably across trials (averaging is generally necessary)

Examples of Averaged ERP Auditory Oddball ERP (average) Targets Nontargets Visual Hemifield ERP (average) Kayser (2001) from Psychophysiology Lab website (http://psychophysiology.cpmc.columbia.edu) time-locked electrical response of a neural system to an electrical or sensory signal Averaged Evoked Potential Evoked Potential (EP) Sch in addition to ry 1989 average of time-locked EPs EPs may vary considerably across trials (averaging is generally necessary) Event-related Potential (ERP) Generalized EP timelocked to a stimulus, response, or in as long as mational event (e.g., missing stimulus in series of stimuli) Applications of ERPs 1) Pathology: 3) Functional mapping: Ramon y Cajal Mountcastle & Henneman(1952) slowing or distortion of EP parallel other neuroanatomical methods 2) In as long as mation processing (incl. perception, cognition)

ERP topographies have anatomical implications! Topographies reflect macroscopic in addition to microscopic anatomy is directly proportional to current I in addition to inversely related to distance (d) EEG Biophysics: Volume Conduction in addition to Ohm’s Law Voltage Potential V= I /R Voltage is directly proportional to current, in addition to inversely related to resistance For a point generator in a conductive medium, resistance is related to distance: Tenke et al (1993)) 4 electrodes point source As the generator becomes wider, the falloff becomes linear in addition to shallow EEG Biophysics: Volume Conduction implies Spatial Integration

EEG Biophysics: Complete Volume Conduction Model Vector as long as m of Ohm’s Law (proportionality of current flow in addition to electric field vectors) This fundamental relationship also underlies inverse models! Current Source Density (Im) is a scalar This is Poisson’s source equation relating current generators to voltage potentials Tenke et al 1993 Problem: Neither current nor voltage are in this equation! Simulated dipole laminae 50% inverted dipoles yield closed field 25% inverted yield open field Field closure is quantitative, not qualitative The Cortical Dipole Depth in mm (orthogonal penetration) in addition to supported superficial-to-deep polarity inversions Intracortical profiles reveal complexity of processing Within cortex field potential profiles reach maximum in addition to invert in deeper layers Tenke et al (unpublished))

A matter of scale: Intracranial recordings ion channels, synaptic currents, postsynaptic potentials in addition to unit discharges (mV range) Intracellular recordings Extracellular recordings Local Field Potentials: postsynaptic potentials in addition to unit discharges Selectivity as long as Local Activity! Multicontact extracellular recordings Local Field Potentials: Summated PSPs, units in addition to multiunits High-impedance electrodes proximal to generators far from external noise sources A matter of scale: Surface in addition to scalp recordings Lower impedance electrodes Larger electrodes integrate over more tissue More distant from generators Further smearing by volume conduction (smaller, composite signals) Additional smearing (bone & skin) Scalp recordings Smaller amplitude compared to EOG, EKG etc. (uV range) Proximity to EMG sources

Flatt, Mike KSLX-FM Overnight On-Air Personality www.phwiki.com

Flatt, Mike Overnight On-Air Personality

Flatt, Mike is from United States and they belong to KSLX-FM and they are from  Phoenix, United States got related to this Particular Journal. and Flatt, Mike deal with the subjects like Rock and Alternative Music

Journal Ratings by Lawrence Technological University

This Particular Journal got reviewed and rated by Lawrence Technological University and short form of this particular Institution is US and gave this Journal an Excellent Rating.