Persistent Link:
http://hdl.handle.net/10150/194972
Title:
Psychometric Properties of Frontal EEG Asymmetry Scores
Author:
Towers, David Norman
Issue Date:
2007
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
Frontal encephalographic (EEG) alpha asymmetry has been proposed as a measure of the relative difference in average cortical activity between the right and left anterior cortex, where this difference is taken as a physiological marker of trait and state level variables associated with affect. The validity of asymmetry as an indicator of both physiological and psychological variables is in part determined by the psychometric properties of asymmetry scores. The present studies focus on the psychometric assessment of frontal alpha asymmetry measured during rest. The first study involves a novel approach in the assessment of the internal consistency reliability of asymmetry scores. Previous studies estimated internal consistency reliability via Cronbach's alpha, using a relatively small set of asymmetry score that summarized activity over segments of the EEG data (e.g. one minute). Such an approach, however, will create estimates dependent on the number of segments utilized rather than the total amount of data recorded. Thus in the first study, individual FFT epochs were treated as items, thereby maximizing the total number of items used to estimate internal consistency reliability. Results of this study suggest internal consistency reliability is greater than previously reported, and as such, the duration of resting EEG data necessary to achieve a reasonable reliability criterion may be shorter than the current standard. In the second study, asymmetry scores were assessed as a specific case of difference scores, which are susceptible to a statistical artifact associated with differences in true-score variance for the component measures. Predicted asymmetry scores associated with the statistical artifact were obtained by estimating the true-score variance of right and left alpha power. The use of hierarchical linear regression showed some influence of the statistical artifact on the relationship between asymmetry scores and a measure of depressive severity, suggesting that some caution may be warranted in interpreting asymmetry results with relatively small effect sizes.
Type:
text; Electronic Dissertation
Keywords:
frontal alpha asymmetry; reliability; difference scores; depression
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Psychology; Graduate College
Degree Grantor:
University of Arizona
Advisor:
Allen, John J.B.
Committee Chair:
Allen, John J.B.

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titlePsychometric Properties of Frontal EEG Asymmetry Scoresen_US
dc.creatorTowers, David Normanen_US
dc.contributor.authorTowers, David Normanen_US
dc.date.issued2007en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractFrontal encephalographic (EEG) alpha asymmetry has been proposed as a measure of the relative difference in average cortical activity between the right and left anterior cortex, where this difference is taken as a physiological marker of trait and state level variables associated with affect. The validity of asymmetry as an indicator of both physiological and psychological variables is in part determined by the psychometric properties of asymmetry scores. The present studies focus on the psychometric assessment of frontal alpha asymmetry measured during rest. The first study involves a novel approach in the assessment of the internal consistency reliability of asymmetry scores. Previous studies estimated internal consistency reliability via Cronbach's alpha, using a relatively small set of asymmetry score that summarized activity over segments of the EEG data (e.g. one minute). Such an approach, however, will create estimates dependent on the number of segments utilized rather than the total amount of data recorded. Thus in the first study, individual FFT epochs were treated as items, thereby maximizing the total number of items used to estimate internal consistency reliability. Results of this study suggest internal consistency reliability is greater than previously reported, and as such, the duration of resting EEG data necessary to achieve a reasonable reliability criterion may be shorter than the current standard. In the second study, asymmetry scores were assessed as a specific case of difference scores, which are susceptible to a statistical artifact associated with differences in true-score variance for the component measures. Predicted asymmetry scores associated with the statistical artifact were obtained by estimating the true-score variance of right and left alpha power. The use of hierarchical linear regression showed some influence of the statistical artifact on the relationship between asymmetry scores and a measure of depressive severity, suggesting that some caution may be warranted in interpreting asymmetry results with relatively small effect sizes.en_US
dc.typetexten_US
dc.typeElectronic Dissertationen_US
dc.subjectfrontal alpha asymmetryen_US
dc.subjectreliabilityen_US
dc.subjectdifference scoresen_US
dc.subjectdepressionen_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplinePsychologyen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorAllen, John J.B.en_US
dc.contributor.chairAllen, John J.B.en_US
dc.contributor.committeememberKaszniak, Alfred W.en_US
dc.contributor.committeememberBootzin, Richard R.en_US
dc.identifier.proquest2220en_US
dc.identifier.oclc659747388en_US
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