The Ability of Mentally Retarded Persons To Judge Facial Expressions From Photographs (1986)
©1986, 2013 by Dallas Denny
Source: Denny, Dallas. (1986). The ability of mentally retarded persons to judge facial expressions from photographs. Paper for Department of Special Education, George Peabody College of Vanderbilt University.
The Ability of Mentally Retarded Persons
To Judge Facial Expressions From Photographs [1] [2]
By Dallas Denny
Department of Special Education
George Peabody College of Vanderbilt University
Nashville, Tennessee
1. Reprints are available from Dallas Denny, Department of Special Education, George Peabody College of Vanderbilt University, Nashville, TN37203
2. The author would like to thank Dr. Carroll E. Izard for allowing the use of his materials.
Summary
Summary
Although there has been considerable study of the ability of normal children and adults to recognize facial expressions, the ability of mentally retarded individuals to recognize facial expressions remains virtually uninvestigated. Seventy-seven mentally retarded adults and nine normal controls were asked to indicate from triads of black-and-white photographs individuals posing the facial expressions anger, distress, fear, interest, joy, and surprise. Analysis revealed that both the control group and grouped experimental subjects correctly identified each of the six expressions more often than would have occurred by chance. When experimental subjects were grouped by functioning level, combined subjects in each group (mildly, moderately, severely, and profoundly retarded) were able to successfully identify the expressions joy and anger. The mildly retarded subjects also identified fear, distress, and interest, and the moderately retarded subjects identified fear. Performance on the present task was shown to be positively correlated with receptive language age. Implications of the findings for the treatment of retarded individuals are discussed.
The bulk of evidence suggests facial expressions are the same for all mankind. That is, people of all cultures express emotions facially in the same manner. For instance, their mouths turn up when they smile, and their lips are compressed and their foreheads furrowed when they are angry (see Ekman, 1963, for an excellent review). Results of cross-cultural studies by Ekman and his associates (reviewed in Ekman, 1980) and Izard (1971) caused those researchers to conclude the same facial expressions are associated with the same emotions, regardless of culture or language, and that facial expressions of emotions are judged similarly across cultures. Ekman (1973) further concluded that while species-constant learning experiences could explain the universality of some facial expressions, others must be genetically determined. This was first argued over a century ago by Sir Charles Darwin (Darwin, 1872).
There has been considerable study of the ability of adults and children of various ages to recognize and produce facial expressions (Izard, 1971). However, the nonverbal communication abilities of mentally retarded individuals have rarely been the object of serious investigation. The evidence which does exist suggests that the ability to identify facial expressions is relatively independent of intelligence.
In a review published in 1964, Davitz reported that Kanner (1931) and Weisberger (1956) found correlations of .21 and .20, respectively, between the ability to identify facial expressions and various measures of intelligence. Levy, Orr, and Rosenzweig (1960) reported that college students and mental retardates did not rate photographs of facial expressions differently in terms of pleasantness. Davitz (1964) concluded:
most researchers have found a low, but positive correlation between the ability to identify facial expressions and various measures of intelligence. (p. 22)
Steiner (1979) found that facial expressions elicited by sweet, sour, and bitter stimuli, as judged by a panel of evaluators, were not different in mentally retarded and normal subjects. Since anencephalic individuals also demonstrated these facial expressions, Steiner concluded facial expressions are mediated by a “hedonic monitor” located in the brainstem.
If Steiner is right—and if there is also an innate, subcortical basis for recognition of facial expressions, then it is to be expected that recognition of facial expressions will be relatively impervious to reduced cortical functioning. If, on the other hand, recognition of facial expression is a mostly learned phenomenon, then it would be expected that there would be a strong direct correlation between intelligence and the ability to recognize expressions. The present, preliminary study was undertaken in order to determine the extent to which mentally retarded adults can discriminate facial expressions from photographs, and the way in which this ability varies with intellectual functioning level. Methodology was similar to that used by Izard (1971), in a cross-cultural study of the ability of children to recognize facial expressions from posed photographs.
Method
Subjects
The experimental group was selected from a pool of about 120 residents of three cottages of Greene Valley Developmental Center, an ACMRDD-accredited state-operated facility located in eastern Tennessee. Individuals who had been previously classified by the facility’s physicians or Speech and Hearing Department as blind, deaf, or nonverbal were dropped from consideration. The remaining individuals comprised the experimental group, which was composed of 77 sensorially intact adults between the ages of 17 and 77 years. The mean age was 45. There were 48 males and 29 females. The measured intelligence of the subjects ranged from borderline to profoundly retarded; two subjects were within the borderline range, 8 were mildly retarded, and the numbers of the moderate, severe, and profound groups were 10, 23, and 34, respectively.
A control group was composed of 9 individuals of presumably normal intelligence. All were staff members of Greene Valley or Clover Bottom Developmental Centers.
Permission to conduct and publish this research was obtained from Greene Valley’s Research, Publications, and Training Committee (RPT). At the RPT’s request, a note was placed in the chart of each participating subject, indicating that the individual had been asked to look briefly at some photographs as part of a scientific research project. The RPT felt that due to the non-noxious and almost recreational nature of the study, permission of the families of the experimental subjects need not be obtained.
Materials
Materials were 8 pictorial triads composed of a subset of the 5 X 7 inch black-and-white photographs used by Izard (1971). There were four photographs each of volunteers posing the six expressions anger, distress (sadness), fear, interest, joy, and surprise. Triads consisted of three of the photographs pasted on a cardboard base. The triads were randomly chosen, with the constraint that the same expression did not appear twice on the same triad.
Procedure
Subjects were asked if they would spend a few minutes looking at pictures. Those who agreed were taken into a quiet area and asked to sit at a table. The triads were then placed one at a time before the subjects and they were asked to choose the photograph which illustrated one of the six expressions. The triads containing the four photographs depicting anger were shown first, followed by distress, fear, interest, joy, and surprise. Thus, each photograph was keyed once, and served as a distractor twice. In order to determine if order of presentation of the keyed expressions was of importance, half of the severely retarded subjects were shown the triads in reverse order; that is, they viewed surprise first, followed by joy, interest, fear, distress, and anger. Requests followed the stems “Which one is…“, “Show me the one who is…“, and “Show me (point to) the one who is…“. The everyday names of the expressions were used. Thus the word mad was used instead of angry, sad or unhappy instead of distressed, afraid or scared instead of fearful, and happy instead of joyful. If the subjects seemed puzzled, a simple descriptive phrase was used (e.g. Interest— “Which one is just looking at something?”). Responses of the subjects, their method of selection, and the approximate time taken by the task were recorded on pre-prepared data sheets.
Results
Eleven individuals in the experimental group refused to look at the pictures. Ten of these were profoundly retarded, and the eleventh was severely retarded. Refusal was usually behavioral: i.e., the subject steadfastly looked away or refused to sit upon request.
Subjects in the control group indicated their choices by pointing (n=5), by verbal statements (n=3), or by a combination or both (n=1). Most subjects in the experimental group understood that they were expected to indicate one of the pictures in each triad and did so. Pointing was the most commonly used method of indicating a photograph, but 2 subjects verbally selected and one used a combination of pointing and verbal statements.
There were several deviant response sets in the experimental group, and individuals who exhibited them were dropped from the analysis. The first was perseveration. The perseverators showed a position preference, repeatedly selecting the leftmost, center, or rightmost photograph. This response set was immediately apparent upon viewing the data sheet, but perseveration was operationally defined as 7 or more consecutive selections or 2 instances or 5 or more consecutive selections of the same position. Of 19 perseverators, 12 were profoundly retarded, 5 severely retarded, 1 moderately retarded, and 1 mildly retarded.
A second deviant response set involved pointing at all three photographs. Four subjects, 3 of whom were profoundly retarded and the fourth severely retarded, pointed in this manner. Another individual repeatedly pointed as soon as the triads were presented, before being asked to discriminate an expression.
After subjects with deviant response sets had been dropped from the analysis, the number remaining for analysis was as is shown in Table 1. Due to the small number of subjects in the borderline group (n=2), data for the borderline subjects were not tabulated, but will instead be discussed in the text.
Combined experimental and combined control subjects correctly identified more keyed expressions than would have occurred by chance (p<.05, chi-square test). Compared to the control group, the experimental group was less efficient at correctly identifying expressions (p<.05, two-tailed, t-test). Combined control and combined experimental subjects identified all six expressions significantly more often than would have been expected by chance (see table). When the experimental subjects were grouped by functioning level, combined subjects in each group (mildly, moderately, severely, and profoundly retarded) were able to successfully identify the expressions joy and anger (Table 1). The mildly retarded subjects also identified the expressions fear, distress, and interest, and the moderately retarded subjects identified fear. One-way ANOVA revealed a significant group effect (p<.01) for the experimental group. Statistical tests were not practical for the two borderline subjects, who correctly identified 62 and 91 percent of total photographs, respectively.
There was no significant difference between subjects who viewed the photographs in standard order and those who viewed them in reverse order (p>.05, two—tailed, t—test).
Discussion
The current results indicate that in mentally retarded adults the ability to identify facial expressions from photographs increases with intellectual level. Similarly, as children mature, their ability to identify expressions from photographs increases. The ability of children to discriminate facial expressions from photographs was demonstrated by Odom & Lemond (1972) and Denny, Denny, & Rust (1982). The methods used by these researchers were methodologically similar to this study, and in some cases the same photographs were used.
Izard found that three-year-olds are reasonably adept at discriminating joy, fear, distress, surprise, and especially anger, but are somewhat less able to discriminate disgust and interest. As with the retarded adults in this study, the expressions most often identified correctly by three-year-olds were joy (62.5%) and anger (85.0%). Between the ages of 3 and 5 the discriminative ability of the children improves markedly, although by age 5 interest is still not correctly identified.
It is likely that in tasks like Izard’s (1971), young children and intellectually impaired adults recognize some expressions which they cannot communicate. This is because they have limited vocabularies which do not include terms such as interest and surprise. To see how the performance of the experimental subjects on the present task varied with language age, the Speech and Hearing records of the subjects were examined. When performance was correlated with results of tests of receptive language, a positive relationship was discovered (r=.5833, p<.01).
Discriminative cues available from photographs are limited (Ekman & Friesen, 1975). For instance, an expression grows on a face, rather than suddenly appearing, is maintained for a variable period of time, and eventually decays. The rates of growth and decay of the expression provide cues about the intensity of the underlying emotion. Non-facial cues also play a part in discriminating emotional states. Antecedent events and learning history, body posture and movements, vocalizations, proximity and relationship of individuals to each other, and cultural factors are all important in judging emotional states and predicting the behavior of others. In everyday life, both individuals of normal intelligence and mentally retarded individuals are subjected to cues which cannot be captured by a photograph. These cues were not available to the experimental group, yet even the group with the lowest level of intellectual functioning was still able to identify some expressions.
Emotional expressiveness is an integral part of being human, or even mammalian (Andrew, 1963). If emotion is mediated by sub-cortical structures (cf Sagan, 1977), then production and recognition of emotions may be relatively independent of the cerebral cortex. Casual observations of mentally retarded individuals certainly indicate that they do respond to facial expressions and many other nonverbal cues.
If profoundly retarded persons can discriminate that others are happy or angry, then the manner in which others relate nonverbally to the retarded is of obvious importance. This would seem especially true in large residential institutions, where many staff may be in attendance. Tenseness, dislike, hostility, and fear may be, and probably too often are, the unwittingly transferred facial messages of individuals who come into contact with the retarded. Also, facial expressions and body postures which convey these emotions may trigger undesirable behavior, and may go a long ways towards explaining why individuals may be much “better” behaved when being attended by certain staff.
It is possible to learn to accurately “read” the facial expressions of others and, by practice in front of a mirror, to become more aware of one’s own facial expressions (c.f. Ekman & Friesen, 1975). This can help in better understanding and in improved ability to predict the behavior of others. Such skills will be of benefit when working with retarded individuals, who often cannot express their needs verbally, but who can nonetheless recognize the facial expressions of those around them. A short discussion of nonverbal communication, with particular emphasis on facial expressiveness, should be and can easily be incorporated into in-service training curricula of agencies which provide services for the retarded.
References
Andrew, R.J. (1963). Evolution of facial expressions. Science, 142, 1034-1041.
Darwin, C. (1872). The expression of the emotions in man and animals. New York: D. Appleton & Co.
Davitz, J.R. (1964). A review of research concerned with facial and vocal expressions in emotion. In J.R. Davitz (Ed.). The communication of emotional meaning. New York: McGraw-Hill Book Co.
Denny, D.; Denny, L.J.; & Rust, J.R. (1982). Preschool children’s performance on two measures of emotional expressiveness compared to teacher ratings. The Journal of Genetic Psychology, 140, 149—150.
Eibl-Eibesfeldt, I. (1970). Ethology: The biology of behavior. New York: Holt, Rinehart, & Winston.
Ekman, P. (1980). The face of man: Expressions of universal emotions in a new Guinea village. New York: Garland Press.
Ekman, P. (1973). Cross-cultural studies of facial expression. In P. Ekman (Ed.), Darwin and facial expression: A century of research in review. New York: Academic Press.
Ekman, P.; & Friesen, W.V. (1975). Unmasking the face. Englewood Cliffs, N.J.: Prentice-Hall, Inc.
Ekman, P.; Friesen, W.V.; & Ellsworth, P. (1982). Conceptual ambiguities. In P. Ekman (Ed.), Emotion in the human face (Second Edition). Cambridge: Cambridge U. Press.
Izard, C.E. (1971). The face of emotion. New York: Appleton-Century-Crofts.
Kanner, L. (1931). Judging emotions from facial expressions. Psychological Monographs, 31(3).
Levy, N.; Orr, T.B.; & Rosenzweig, B. (1960). Judgments of emotion from facial expressions by college students, mental retardates, and mental hospital patients. Journal of Personality, 28, 342-349.
Odom, R.D.; & Lemond, C.M. (1972). Developmental differences in the perception and production of facial expressions. Child Development, 43, 359-369.
Sagan, C. (1977). The dragons of Eden: Speculations on the evolution of human intelligence. New York: Random House.
Steiner, J.E. (1979). Human facial expressions in response to taste and smell stimulation. Advances in Child Development and Behavior, 13, 257-295.