Dichotic Listening As a Tool For Validating Alternative Measures of Brain Lateralization

ABSTRACT - Brain lateralization has become popular in communication planning, advertising testing, and personal development in later years. It has been suggested that whereas the left brain specializes in verbal analytical tasks, and does so in a sequential manner being able consciously to report-about what is going on, in contrast the right brain is unconscious, nonverbal, synthetic, holistic, concerned with spatial relationships and to a larger extent emotionally controlled.

Citation:

Flemming Hansen (1983) ,"Dichotic Listening As a Tool For Validating Alternative Measures of Brain Lateralization", in NA - Advances in Consumer Research Volume 10, eds. Richard P. Bagozzi and Alice M. Tybout, Ann Abor, MI : Association for Consumer Research, Pages: 182-183.

Advances in Consumer Research Volume 10, 1983      Pages 182-183

DICHOTIC LISTENING AS A TOOL FOR VALIDATING ALTERNATIVE MEASURES OF BRAIN LATERALIZATION

Flemming Hansen, Copenhagen School of Business Administration and Economics

[For more information regarding the Magert write to: Flemming Hansen, The Copenhagen School of Business Administration and Economics, Howitzvey 60, Copenhagen F, 2000bk DENMARK.]

ABSTRACT -

Brain lateralization has become popular in communication planning, advertising testing, and personal development in later years. It has been suggested that whereas the left brain specializes in verbal analytical tasks, and does so in a sequential manner being able consciously to report-about what is going on, in contrast the right brain is unconscious, nonverbal, synthetic, holistic, concerned with spatial relationships and to a larger extent emotionally controlled.

These differences may appear in varying situations; that is, some tasks may appeal more to "left hemisphere processing," whereas others tend to activate "right hemisphere processing" more. Individuals, however, may also differ in the extent to which they--faced with similar tasks--rely upon left vs. right hemispheres.

A closer-view at some of the commercial applications of these findings suggest, however, that these applications rely on measurements, the validity of which are not very well documented.

Actually, validation studies concerned with techniques for studying hemispherical lateralization in normal individuals are almost nonCexistent.

In the present paper, alternative measures are discussed and focus is set upon the use of self-administered questionnaires and upon the use of dichotic listening.

FOUR ALTERNATIVE SELF-ADMINISTERED QUESTIONNAIRES

Richardson (1977) has published a 25-items verbalizer-visualizer scale. This scale has been developed by comparing responses to the items included in the test with lateral eye-movements (a measure believed to reflect brain lateralization). A second instrument has been used in earlier research by Hansen/Lundsgaard (1981). This consists of 40 items selected from a large number of potential candidates, partly through factor analyses, partly through comparison with selected clinical psychological tests such as work recognition test, picture recognition test, cube test, digit span test, etc. The 40 items are administered as Likert type scaled items with the respondents agreeing or disagreeing in the statements set forward.

A third instrument, composed of 20 forced choice questions, has been reported by Donegan. The items have some similarity with the Richardson and the Hansen/Lundsgaard items, but no attempt has been reported validating this battery. Finally, a more complex "brain dominance instrument," developed and commercially used by Ned Herrmann, is included.

In the present study all these four instruments were administered to a sample of 55 male and female students living in a mixed university housing. Based upon this, scores on the various scales are compared, and it is concluded that the four questionnaires seem to a greater or lesser extent to be measuring the same underlying phenomenon. It appears that whereas the first four Herrmann-indicators relate quite well to each other (and in the expected direction), some of the negative correlations are ascribed to the fact that the scoring of some of the items is reversed. Similarly the Richardson, the Hansen/Lundsgaard/the Donegan, and the question-index from the Herrmann instrument also correlate quite well among each other. The relationship between, on the one hand, other of the Herrmann-indicators, and the four self-administered questionnaires, is somewhat less convincing, although significant correlations exist.

DICHOTIC LISTENING

Dichotic listening is a technique based upon the observation that information sent to the left ear initially is received in the right brain half and vice versa. When conflicting information is sent to the left and right ears at the same tire, the information the individual chooses to process reflects tendencies to rely more or less upon left or right brain Processing.

In earlier work (Hansen/Lundsgaard, 1980 and 1981) I have tried to work with different versions of this technique, and I have compared the results with measurements obtained with the use of other techniques generally believed to reflect differences in left vs. right brain processing. Surprisingly enough, very few attempts have been made in the past to cross-validate such different measurement techniques, and those attempts which have been published do not at all look convincing.

In the presentation, these problems are discussed and some of the implications that follow from the scarce evidence regarding the validity of the measurements applied are touched upon.

Eventually, a new revised dichotic listening technique is being described and initial results with [ this technique are compared with findings from - previous studies. At the present time, it seems i that the new technique has a such improved reliability as compared with techniques used in the past.

THE RELATIONSHIP BETWEEN DICHOTIC LISTENING AND SELF-ADMINISTERED QUESTIONNAIRES

In the presentation the correlations between dichotic listening scores and the measurement obtained with the 4 self-administered questionnaire instruments are reproduced, All correlations are small, and some in the wrong direction!

Altogether, therefore, the present study suggests that what is being measure 1 with available self-administered questionnaires, is not the same as what is being measured with dichotic listening. With an eye to the difficulties involved in establishing meaningful indexes of brain lateralization in studies using EEG-measures reported elsewhere, it is concluded that at the present time it seems far from obvious how we can and should measure hemispherical lateralization in normal individual.

Altogether it is therefore tempting to warn against oversimplifying applications of existing measures of hemispherical lateralization before more is known about what is actually being measured with the various instruments administered.

REFERENCES

Bunderson, C.V., J.. Olsen and W.E. Herrmann (1981), "Patterns of Brain Dominance and Their Relationships to Tests of Cognitive Processing, Personality, and Learning StYle." unpublished paper.

Hansen, F. & N.E. Lundsgaard (1980), "Developing an Instrument to Identify Individual Differences,"  in the Processing of Pictorial and Other Non-Verbal Information, Kent B. Monroe (ed.), Advances in Consumer Research, Vol. VIII, Ann Arbor, Michigan.

Hansen, F. & N.E. Lundsgaard (1981), "A Comparison of Alternative Measures of Individual Differences in Brain Lateralizaton," A Mitchell (ed. ), Advances in Consumer Research, Vol. IX, Ann Arbor, Michigan.

Richardson, A. (1977), "Verbalizer-Visualizer: A Cognitive Style Dimension," Journal of Mental Imagery, 1, pp. 109-125.

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