Herbert Krugman's Discovery

"From 1967 to his retirement in 1983, Herbert E. Krugman was manager of corporate public opinion research at the General Electric Company. He was previously research vice president for Marplan, for Ted Bates Advertising, and for the industrial design firm of Raymond Loewy.  Dr. Krugman received his Ph.D. from Columbia University in 1952 and his B.S.S. from CCNY in 1942. He is past-president of the American Association for Public Opinion Research, of the Division of Comsumer Psychology of the American Psychological Association, and of the Market Research Council of New York.  He has served on the faculties of Yale, Princeton and Columbia Universities and has been a trustee of the Marketing Science Institute in Cambridge, a director of the Advertising Research Foundation and chairman of the Research Policy Committee of the Association of National Advertisers. - Herbert Krugman

Excerpts from:

"Brain Wave Measures of Media Involvement", first published in the "Journal of Advertising Research" (Feb 1971) and reprinted in the book How Advertising Works

Brain Wave Experiment

The Neuropsychological Laboratory of New York Medical College is engaged in basic and applied research, and frequently in practical applications. The paid subject in our experiment was a 22-year-old secretary....

Analysis of the brain wave (EEG) data was made on the total reaction to each of the nine commercial exposures, or specifically to 56 seconds of each, to eliminate transition responses. The type of analysis summed up the spectrum, as we name it,  of all identifiable brain wave frequencies emitted during the 56-second epoch, as it is called. In simple terms, one obtains a measure of how many seconds' worth of each wave frequency appears during the 56 seconds...

The computer program reported 11 "bands" or frequency class intervals from 1.5 cycles per second up to 32 cps. The first 5 bands were combined and called slow waves. The next 4 bands, from 7.6 to 12.33 cps, are usually called alpha waves and are associated with relaxation. They were combined and called alpha. The last 2 bands, from 12.3 to 31.8 cps, are usually called beta waves and are associated with alertness, activity and arousal. They were combined and called fast waves...

First the print ad, with 5 seconds of slow waves, 16 of alpha, and 28 of fast waves, all added up to a picture of relaxed attention, interest, and mental activity...

As the first commercial came on, the subject looked up and an entirely new pattern or mix appeared, adding up to 21 seconds of slow, 18 of alpha, and 15 of fast. I say pattern because closer inspection and analysis showed that the wave patterns throughout were, at any one moment, mixtures of the overlapping wave actions. It was not some seconds of one frequency followed by some seconds of another, but an overall state, mode, or style of reception with elements of different wave types. Thus the 21 slow, 18 alpha, and 15 fast in response to the first commercial roughly represented constant proportions of waves active in any one period within the 56 seconds.

We were surprised that the alpha or relaxed element did not change significantly from print to TV, but we took it as a sign of general relaxation in the test situation. We had expected that the TV might be more relaxing, but not that it would instantly produce a preponderance of slow waves and a characteristic mode of response. Rather, we expected that it might develop over time with the three repetitions.

The initial spectrum for the first commercial did not change significantly for the next two commercials. Apparently if was a characteristic mode of response. The 21-18-15 became 24-15-14 for the second commercial, and 24-16-13 for the third... There were, however, differences in the proportion of delta and theta, which together constitute the slow waves. These deserve closer attention in future studies.

The question arises as to how immediate this characteristic mode of response was. Did it appear in the first seconds of the first commercial or what? To answer this, we analyzed spectra for three 10-second periods within the first exposure to the first commercial. Within Seconds 2 to 12, there were

2 seconds of slow, 4 of alpha, and 5 of fast. Within Seconds 25 to 35, there were 4 seconds of slow, 3 of alpha, and 3 of fast waves; and within Seconds 46 to 56, there were 5 seconds of slow, 3 of alpha, and 3 of fast waves.

In other words, it was about halfway through the first exposure to the first commercial before the slow waves predominated over the fast waves. We can say, then, that the characteristic mode of response took about 30 seconds to develop fully...

Interpretation

It appears that this subject's mode of response to television is very different from her response to print. That is, the basic electrical response of the brain is more to the media than to content differences within the TV commercials or to what, in pre-McLuhan days, would ordinarily have been called the commercial message.

It also appears, as suggested initially by the earlier studies of involvement or of eye movement, that the response to print generally may come to be understood as active and composed primarily of fast brain waves, whereas the response to television might be understood as passive and composed primarily of slow brain waves. Further testing is indicated...

Although further work with brainwaves seems indicated, it should be stressed that there is no evidence or speculative inference here to suggest that either print or television is "better" than the other, or that fast or slow brain waves are better than the other...