SOLUTION: origin of the happy face advantage | My Assignment Tutor

actapsychologicaELSEVIER Acta Psychologica89 (1995) 149-163Happy face advantage in recognizing facial expressionsT a k a h i r o Kirita a, *, M i t s u o E n d o ba Shokei Women’s Junior College, 4-1O-1 Yurigaoka, Natori, Miyagi, 981-12 Japanb Hachinohe Junior College, 13-384 Mihono, Hachinohe, Aornori, 031, JapanReceived 3 December 1993;revised 6 April 1994;accepted 14 April 1994AbstractIn this study, the origin of the happy face advantage was examined with respect to themode of processing, as well as the spatial characteristics, of happy faces. In Experiments 1and 2, happy and sad schematic faces of equal form deviations from a neutral face wereadopted as stimuli, and the task of categorizing these two facial expressions was given to thesubjects. Experiment 1 demonstrated that happy faces were recognized faster than sad facesonly when they were presented as in an upright position: conversely the sad face advantagewas observed to be slight when the stimuli were presented as inverted. The results ofExperiment 2 showed that the pattern of recognition for happy faces differed in the rightand left visual fields: the affect of inversion was much more pronounced when the happyfaces were presented in the right visual field than when they were presented in the leftvisual field. From these results, it was assumed that while happy faces were likely to berecognized holistically, sad faces were likely to be recognized by analytic mode. Thisassumption was not rejected by the data from Experiment 3 where the uncontrolled happyand sad expressions on real faces were used as stimuli.1. IntroductionIt has been repeatedly observed that happy or smiling faces are recognizedmore quickly and more accurately than any other facial expression (Ekman et al.,1982; Kirouac and Dord, 1983; Ladavas et al., 1980). However, few researchershave attempted to examine the origin of this happy face advantage in therecognition of facial expressions.Exceptionally, Feyereisen et al. (1986) focused their attention on the happy faceadvantage (emotion category effect in their terms) and conducted a few experi-* Corresponding author.0001-6918/95/$09.50 © 1995 Elsevier Science B.V. All rights reservedSSDI 0001-6918(94)00021-8150 T. lO’rita, M. Endo / Acta Psychologica 89 (1995) 149-163ments to explore its origin. The results of their experiments showed that theadvantage of happiness was not limited to the case of facial expressions: this effectwas also found in the categorization task of words expressing happy and sad states.But it was also found that the advantage was greater when happy and sad facialexpressions were used as stimuli. Based on these results, they suggested that thehappy face advantage depended partly on the internal organization of the emotional field, and partly on the spatial characteristics of happy faces. Unfortunately,they did not clarify what aspects of the spatial characteristics of happy facesyielded such an advantage. In this study, we will examine this problem.Primary consideration is likely to be given to the possibility that the happy faceadvantage depends exclusively on a specific local feature. For example, a U-shapedmouth might be responsible for the recognition of happy faces, because only happyfaces have such a salient feature. Our preliminary experiment, however, showedthat there was no difference in reaction times needed for categorizing simpleU-shaped and inverted U-shaped line segments. Rather, this result suggests thatthe U-shaped mouth by itself might have no effect on the happy face advantage.Alternatively, the global characteristics, instead of local feature, of happy facesmay give rise to such an advantage. In this case, however, the question arises as tohow facial expressions should be characterized globally. Although all facial expressions can be described in terms of total deviations from a neutral face, it is unlikelythat only happy faces should deviate so much. Furthermore, such a definitionwould be meaningless unless it is verified that our brain systems actually useinformation concerning global deviations in classifying facial expressions.Yet little has been discovered about the process for recognizing facial expressions. For example, it is still uncertain whether all facial expressions are processedin the same way; or if the way of processing changes depending on the facialexpression. For the latter case, happy faces are likely to be recognized by quite adifferent strategy. Interestingly, the recognition of happy faces has been said toplay an important role in infant-mother communications (Bowlby, 1969). In fact,regardless of their insufficient visual acuities, young infants are known to firstdiscriminate happy faces from all other facial expressions (LaBarbera et al., 1976;Young-Brown et al., 1977; Barrera and Maurer, 1981). Thus, starting with infancy,there is good reason to believe that happy faces are recognized in a different way.So far, we have discussed two possible explanations for the happy face advantage. One is concerned with the spatial factors of happy faces such as local orglobal deviations from a neutral face. The other assumes specific way of processingfor happy faces. These two explanations seem to offer quite different predictionsfor this phenomenon. While the former view would predict that the happy faceadvantage disappears or, at least, is reduced when the spatial deviations arecontrolled, the latter view would predict that this advantage should be influencednot by spatial factors but by the presentation variables such as stimulus orientations, durations and visual fields, which have been assumed to affect the mode ofprocessing; that is, the mode would shift from holistic to analytic processing or viceversa depending on those variables (Sergent and Bindra, 1981).In this study, besides controlling the spatial deviations of happy and sadT. Kirita, M. Endo /Acta Psychologica 89 (1995) 149-163 151schematic faces from a neutral face, we examined the effects of stimulus durations(Experiment 1) and visual fields (Experiment 2), as well as the effect of stimulusorientations on the happy face advantage. Experiment 3 was carried out toreplicate the results of Experiment 2 using uncontrolled happy and sad expressionson real faces.2. Experiment IIn this experiment, several happy and sad schematic faces were used. Theirlocal, as well as global, form deviations from a neutral face were approximatelyequal. The task of categorizing happy and sad faces was given to each subject withthe orientations and the durations of the stimuli being varied.2.1. MethodSubjectsFourteen students of Tohoku University (7 males and 7 females) participated inthe experiment. All subjects were right-handed.Stimuli and apparatusHappy and sad schematic faces, which had been evaluated by Kirita (1994),were used as stimuli. The process of stimulus evaluation was as follows. In hisresearch, Kirita made a standard (neutral) schematic face composed of eyebrows,eyes with pupils, a nose and a mouth (see Fig. 1). To examine the contributions ofthe angle of eyebrows, the location of pupils and the shape of mouth, to theperceived emotions, 22 sample schematic faces were made by systematicallyvarying these variables and printed on separate sheets with a list of 12 emotioncategories. Sixty-six independent subjects were instructed to select one appropriateemotion category for each schematic face from the list.Frequency data matrix was first analyzed by Dual Scaling (Nishisato, 1980).Three orthogonal solutions were obtained, by which both 22 schematic faces and12 emotion categories were weighted. These three solutions could be interpretedas dimensions of emotion i.e. access-avoidance, pleasantness- unpleasantness andtension-relaxation. Then by using a categorical multiple regression analysis(Hayashi, 1952), he examined whether the locations of schematic faces in threedimensional space of emotion could be predicted by their components. For eachdimension, multiple correlation coefficient exceeding 0.9 was obtained, indicatingthat the predictions were successful. From this analysis, it was found that combinations of horizontal or medially downturned eyebrows and U-shaped mouth contributed to happiness. Likewise, mediallyupturned eyebrows and inverted U-shapedmouth made the schematic faces look sad. The location of pupils had little effectfor both emotions.In this experiment, a combination of medially downturned eyebrows and Ushaped mouth was chosen for making happy faces so that their local, as well as152 T. Kirita, M. Endo /Acta Psychologica89 (1995) 149-163J JFig. 1. Standard schematicface(left) and expamplesof happy(middle)and sad (right)faces.global deviations from the neutral face should be approximately equal to those ofsad faces. Five happy and five sad faces were made by mainly varying the locationof pupils. Examples of the stimuli are shown in Fig. 1.The stimuli were presented on the screen of a TV-type tachistoscope (IwatsuISEL: IS701-A). The subjects, with their heads immobilized by a chin rest,observed them at a distance of 100cm. The size of the stimuli was 3.4° x 3.4° . Tworesponse keys connected to the tachistoscope were used to measure reaction times.DesignA 2 x 2 x 2 factorial design was used. The three factors were Emotion (happyand sad), Orientation (upright and inverted), and Duration (100 and 300 msec).ProcedureThe experiment was carried out in a dark room. Before the experiment thesubjects were shown each schematic face for 3 sec to confirm the emotionexpressed by it. Each experimental trial was begun by presenting a small fixationpoint for 2 sec, which was immediately followed by one of the 10 schematic facespresented as either upright or inverted for either 100 or 300 msec. These stimulusdurations were determined in accordance with the implications found in thestudies of laterality that the critical duration dissociating two modes of processingshould be somewhere around 200 msec (see Sergent, 1982,1983). The subjects’ taskwas to decide whether the schematic face expressed happiness or sadness asquickly and accurately as possible. The decision was made by pressing one of tworesponse keys located beneath the index fingers of both hands. One second afterthe subject pressed one of the two response keys, the fixation point for the nexttrial was presented. Each schematic face appeared four times under each condition, thus 160 trials (5 faces x 4 times x 8 conditions) were performed. The orderof presentation was random. Before the experimental session, the subjects weregiven 20 practice trials using the same stimuli. The response keys were counterbalanced across the subjects.2.2. ResultsFor each subject, the mean correct RT and error rate were calculated for eachcondition. Eight correct responses which exceeded the 2 see limit were treated asT. Kirita, M. Endo /Acta Psychologica 89 (1995) 149-163 153,,,,- 20u JLLI 0.1).The alternative analysis of the simple simple main effect of Orientation indicatedthat the inversion effect was significant only for happy faces (F(1,27)= 49.9,p 0.1). The alternative analysis of Visual Field at two levels of Emotionrevealed that for the happy faces the subjects made slightly more errors in the rightvisual field than in the left visual field (F(1,19)= 3.11, 0.05