Newborns Discriminate Schematic Faces from Scrambled Faces

Article excerpt

Abstract Newborn attention to, and discrimination of, facelike patterns was examined in three experiments employing 35 one- to three-day-old infants. Differential eye tracking and head turning to three moving stimuli (a schematic face, a scrambled face, and a luminance-matched blank) were measured in two of the three experiments. The newborns turned their eyes and heads farther to follow patterned stimuli, containing facelike features, than to a luminance-- matched blank, but they did not turn farther to a stimulus with the features arranged in a facelike manner compared to features scrambled. A third experiment tested newborns' ability to discriminate between the facelike and scrambled face patterns. Using an infant-controlled procedure, infants showed similar initial fixation times and similar numbers of trials to reach a 60% response decrement criterion to both patterned stimuli. Following habituation, novelty responding indicated that infants discriminated between the schematic face and the scrambled face patterns. Although infants did not show a preference for a facelike stimulus compared to a features-scrambled pattern in the present experiments, they could discriminate the two patterns based on the internal arrangement of the facial features.

Whether human newborn infants perceive face stimuli preferentially is a controversial issue. Some researchers (e.g., Johnson & Morton, 1991) argue that infants are innately drawn to the human face from birth and that this attention is the first critical step in the development of socialization. Others argue that a face pattern is perceived in a manner similar to other stimuli which share particular attributes (e.g., ovals, curves, high-contrast areas, or the optimal amount of amplitude information/pattern complexity; Kleiner, 1993). The question of whether a face is a special stimulus, perceived differently or preferentially by the newborn, is of interest to both developmental and perceptual psychologists, especially since the publication of Johnson and Morton's (1991) two-process model of face perception.

According to Johnson and Morton (1991), newborns have a subcortical mechanism, CONSPEC, which serves to orient rudimentary attention to the human face. Its functioning declines between one and three months of age, during which period a second mechanism, CONLERN, is asserting itself. This mechanism is hypothesized to be a generic mechanism that serves to drive the infant to learn about the specifics of human faces. Because of its increasing influence on the infant's orientation toward faces, Johnson and Morton argue that most infants approaching three months of age will show clear interest in faces. Indeed, many researchers have demonstrated a face preference in infants two months of age or older (e.g., Fantz, 1965; Haaf & Bell, 1967; Kagan, Hanker, Hen-Tove, & Lewis, 1966; Maurer & Barrera, 1981). However, support for a similar preference by newborns is equivocal. Whereas some investigators have reported demonstrating a newborn face preference (e.g., Fantz, 1963; Fitzgerald, 1968; Goren, Sarty, & Wu, 1975; Stechler, 1964), others have not (e.g., Easterbrook, Kisilevsky, Hains, & Muir, 1999; Haaf, 1974; Hershenson, 1964; Thomas, 1965).

Using adaptations of Fantz's (1958) visual preference technique, infants' interest in face patterns has been examined by presenting newborns with static patterns (e.g., Fantz, 1963; Hershenson, 1964), photo-images (Slater et al., 1998), or still-life faces (Bushnell, Sai, & Mullin, 1989; Pascalis, DeSchonen, Morton, Deruelle, & Fabre-Grenet, 1995). Using patterned and coloured stimuli, Fantz (1963) found that infants preferred to look at a face pattern when it was presented along with any other pattern from his stimulus set. In contrast, Hershenson (1964) reported that newborns preferred patterns of low to intermediate complexity or of intermediate illumination. Recently, Valenza, Simion, Cassia, and Umilta (1996) examined newborns' orientations to Morton and Johnson's (1991) config, a facelike stimulus containing two square blobs for the eyes and one square blob for the mouth. …