Aesthetic preference and lateral preferences

M)28-3932,86 $3.00+0.00

Neuropsychologia, Vol. 24, No 4. pp. 5X7-590. 1986.

Pergamon Journals Ltd.

Printed in GreatBritain

NOTE AESTHETIC

PREFERENCE

AND LATERAL

PREFERENCES

JOHN P. MCLAUGHLIN Department

of Psychology,

University

of Delaware,

Newark,

DE 19716, U.S.A.

(Received 28 January 1986) Abstract-Subjects expressed preference for original or mirror-reversed versions of paintings. Hand preference predicted a significant proportion of the choice variance, but eye, foot and ear preference did not, nor did family sinistrality.

INTRODUCTION PAINTINGS that are pleasing

have the characteristic, among others, that the principle figure or major area of interest is located to the right of the physical center of the picture. This was noted early in this century by Woelfflin, cf. [2] and more recently by GAFFRON [2], who elaborated Woelfflin’s idea that viewers scanned through a painting beginning in the lower left of the picture space and curving up, in and to the right in that space. She believed that the curved scan path ‘. permits the most complete, unfalsified impression of three-dimensional space by visual perception’ [p. 3291. While Gaffron’s approach was phenomenological, others recently have provided more precise data on preferences for paintings. The findings generally support the contention that aesthetic preferences are determined, in part, by the greater dependence of some psychological functions on one cerebral hemisphere than the other. LEVY [3] reported that right-hemisphere (RH) subjects chose preselected photographs over their mirror-images at a rate greater than chance. By contrast, left-hemisphere (LH) subjects’ choices did not reveal any systematic preference for either version. In another study, Levy showed that the versions chosen by RH subjects were rated by new subjects to have their areas of interest and/or weight shifted toward the right half of the image. These data and recent theories of cerebral organization led LEVY [S] to conclude.

‘ in viewing pictures, the right visuo-spatially specialized hemisphere is selectively activated, producing a bias ofattention toward and a psychological weighting of the left side of space. Pictures which correct for this imbalance by having their more important content or greater heaviness on the right are considered to be more aesthetically pleasing.’ [p. 4421. A somewhat different pattern of findings was reported by MCLAUGHLIN et al. [4]. Using pictures of paintings as stimuli, they found that RH and LH subjects expressed definite and opposite preferences, with RH subjects preferring versions with major areas of interest to the right of center and LH subjects choosing the mirror-reversed versions. In a second experiment, the two groups were again different from each other, but the choices of RH subjects were at chance, while the LH subjects again expressed preference for versions having the major area of interest to the left side of the painting. There was a consistent direction of difference between RH and LH subjects’ preferences in the studies reported by LEVY [3] and by MCLAUGHLIN et al. [4]. In each study the RH sample chose more versions with the major area of interest on the right than did the LH sample, although the absolute scores were sometimes at chance. One possible source of the variation in findings is the degree to which the relevant psychological functions are lateralized within an individual (cf. Cl]). For example, it has been shown by, for example, P~RAC and COREN [S], that expressions of preference for the use of an organ on one side of the body are not entirely consistent, i.e. a person may write with one hand, but throw with the other. Moreover. left-handers who report other left-handers in their immediate family may be more different from right-handers on some tasks than are left-handers without such family sinistrality [6]. Since choice of hand for writing roughly predicts aesthetic judgment, consistency of hand preference in a number of situations may be a more fine predictor. If it is, the psychological functions most directly related to this aesthetic task would be even more clearly related to hand preference, and be seen as functions that vary in degree of lateralization. Another possibility is that this aesthetic preference is related not merely to hand use, but to the degree that many functions are lateralized. PORAC and COREN [S] have reported that the correlations between pairs of scores 587

describing hand, foot, ear and eye preference are not high, with values ranging from 0.22 to 0.53, indicating that these preferences are somewhat independent of each other. If this aesthetic preference depends on the total amount of preference for one side of the body over the other, more reliable prediction of picture choice will be obtained from the use of many measures of lateral preference than from hand preference alone. The purpose of the present experiment, then, was to determine the relations among: (1) preference for paintings with areas of interest to the right or to the left of center; (2) measures of lateral preference for the use of hands, feet, eyes and ears; and (3) a measure of family sinistrality. An obvious prediction is that the more consistent are preferences for use of one side of the body, the greater will be the preference for paintings with the major area of interest in that side of the picture space. At the other extreme, handedness may remain as the only correlate ofpicture preference.

METHODS

To ensure a reasonable number of subjects with preference for some left organs, students in Introductory Psychology courses were asked two questions, ‘Which hand do you use? and ‘Which eye would you use to sight a rifle?’ Based on these responses, 24 LH and 24 RH students were selected so that 12 LH and I2 RH students preferred to use the right eye. No one had any knowledge of the purposes or hypotheses of the experiment, Materials

Twenty-seven paintings were selected from materials used in earlier work 141. Each of these paintings had been judged to be asymmetric, i.e. the principal figure or the major area of interest was either to the right or to the left of the center of the painting. A questionnaire was devised by taking the 13 items standardized by P~KACand COKEN[S] and adding four others. The Porac and Coren items ask subjects to report their preference for the use of hand, eye, foot and ear and allow one of three responses; right, left or both. The additional four items estimated family sinistrality. Two Kodak Carousel projectors with zoom lenses were used to project duplicate 35-mm slides of a painting on a screen, one above the other. The projected images were 473 times the size of the slide in area. Luminance reflected by the screen from an unfiltered beam was 44 foot lamberts. Procedure

Subjects were tested individually, seated 10 ft. from the screen in a chair with an attached writing easel. The two versions of each painting were projected simultaneously in a dimly-illuminated room. Fourteen pictures with an imbalance toward the right (IR). i.e. with the major area of interest toward the right, and 13 with an imbalance toward the left (IL) were in the upper position. Subjects indicated their choices of which member of a pair they found more aesthetically pleasing on scan sheets for later computer scoring. During this time and while writing their names on the sheets, their hand preference for writing was verified. Each pair was exposed for I5 sec. followed immediately by the next pair. Eye preference was confirmed by having subjects view a slide in a monocular viewer at the end of a session, but no other confirmatory tests were performed. After completion of the painting preference judgment, subjects filled out the questionnaire.

Each subject was scored for the number of times she/he chose an IR version for an R-score and the number of times she/he chose an IL version for an L-score. Difference scores (D) were then calculated according to the formula D = R - L, so that positive scores indicated a preference for IR versions and negative for IL versions. Responses to the 13-item questionnaire were given 1 point for each R response and - 1 for each L or B response, after PORAC’and COKEN [S]. Separate preference scores were then calculated for Hand(H). Eye (Ey), Ear (Er) and Foot(F). Finally, a family sinistrality (FS) score was calculated by assigning a score of + I for each left-handed or ambidextrous person in the subject’s immediate family.

RESULTS

AND DISCUSSION

Subjects were classified as RH If they had positive scores for hand preference and LH if scores were at zero or negative. The resulting classification was identical to that obtained in the initial selection, but eight RH and seven LH subjects did not get maximum RH and LH scores. Skew was virtually nonexistent: -0.15. A majority obtained maximum R and L scores for F, Er and Ey: 60%. 79% and 77%. respectively. Positive skew, 1.12 and 1.48. was observed for F and ER, and negative (- I .22) for Ey. Half of the LH subjects reported no LH parent or sibling, eight reported one and four reported two, The corresponding numbers for RH subjects were 14, 8 and 2, respectively.

589

NOTE

The D-scores were first examined to determine whether the findings reported by MCLAUGHLIN el al. [4] were duplicated. The mean D-scores for RH and LH subjects were 2.58 and - 1.42, respectively, which were reliably different, t=3.78, PO.OS). The contribution of Ey was too small to be included by the analysis. Since the current lateral preference scores were not from nearly as large a sample as PORAC and COREN [S] described, they were compared with those norms to detect any differences. Table 2 contains the matrix of correlations among the four lateral preference measures for the current experimental example and the corresponding values reported by PORAC and COREN[S] for their large sample. While the absolute values differ for any given comparison, the relative magnitudes are similar, e.g. ear preference correlates least with eye preference and most with foot preference in each sample. To evaluate this similarity, the corresponding coefficients in each matrix were treated as scores and correlated with each other. That value was 0.72, supporting the general impression of similarity. There remains a possibility, of course, that the selection of equal numbers of RH and LH subjects biased the results. The major finding in this study was that hand preference predicted a substantial and significant proportion of the variance in the choice of versions of paintings. The more uniform the preferences for the right hand, the more the IR version was chosen and vice versa. To the extent that hand preference is related to differential lateralization of functions, the finding implies that some psychological mechanisms related to this type of aesthetic preference are also differentially lateralized. At the same time, hand preference accounted for 17% of the variance in the aesthetic preference score, leaving 83% to be explained. Some of this, of course, was error variance and some is probably because many LH subjects seem to have the same cerebral organization as RH subjects 133. Other measures of lateral preference did not account for any appreciable variance in the aesthetic choices. Assuming that each of these preferences reflects the lateralization of some specific function, then aesthetic preference

Table 1. Summary of stepwise regression analysis with aesthetic choice predicted by Hand (H), Ear (ER), Foot (F), and Eye (EY) preference and Family Sinistrality (FS) Variable

Simple r

H F FS ER EY

Multiple

0.417 0.218 0.044 0.236 0.115

r

0.417 0.443 0.455 0.459 -

0.174 0.196 0.207 0.211

Table 2. Product-moment correlations among Hand (H), Eye (EY), Foot (F) and Ear (ER) preference and Family Sinistrality (FS). Comparable values from PORAC and COREN [S] are in parentheses. H

EY

F

EY

0.270 (0.310)

F

0.756 (0.527)

0.177 (0.264)

ER

0.572 (0.247)

0.309 (0.216)

0.626 (0.354)

FS

-0.099

- 0.069

0.000

ER

- 0.086

590

NOTE

is not determined by an accumulation of these lateralized functions. Rather, the findings suggest that aesthetic choice is related to some specific mechanisms that are also related to hand preference but are independent of the other preferences. In other words, this type of aesthetic choice is not controlled by some global dominance of one side of the body over the other. Instead, it is influenced by some mechanisms that are indifferent to the lateralization of others. As LEVY [3] suggested, one direction for future research is to explore the psychophysics of picture asymmetry to better understand its relation to aesthetic preference. Another tack is to explore the correlations between aesthetic preference and other tasks for which cerebral lateralization is known to be important. Both lines of investigation should lead to a better understanding of the nature and organization of the psychological processes that determine the experience of beauty.

Acknowledqrmenf-The data.

author isgrateful

to Steve Bryk, Brandi Klein and Patti Perillo for collecting

portions

ofthe

REFERENCES BKAIXHAW. J. L. and NETTLETON,N. C. Human Crrrhral Asymmetry. Prentice-Hall, Englewood Cliffs, NJ, 1983. GAFFRON. M. Left and right in pictures, ~Irr Q. 13, 312-331, 1950. LEVY, J. Lateral dominance and aesthetic preference. Neuropsychologia 14, 431445, 1976. MCLAUGIWN, J. P., DEAN, P. and STANLEY, P. Aesthetic preference in dextrals and sinistrals. Nruropsycholoyiu 21, 147 153, 1983. POKAC, C. and COR~N, S. Lateral Prej&mcss and Human Behavior. Springer-Verlag, New York, 1981. ZUKIF, E. B. and BKYUEN,M. P. Familial handedness and left right differences in auditory and visual perception. Nruropsychologia 7, 179- 187, 1969.