Infants and Children in Context. Tara L. Kuther

conditioning occurs more quickly and to a broader range of stimuli. For example, in a classic study, Watson and Raynor (1920) paired a white rat with a loud banging noise to evoke fear in an 11-month-old boy known as Little Albert. Repeated pairings of the white rat with the loud noise made Albert cry even when the rat was presented without the noise. In other words, Little Albert was conditioned to associate the neutral stimulus with the conditioned stimulus. Albert demonstrated fear in response to seeing the rat, indicating that emotional responses can be classically conditioned. Our capacities to learn through classical conditioning are evident at birth—and persist throughout life.

      Operant Conditioning

      At birth, babies can learn to engage in behaviors based on their consequences, known as operant conditioning. Behaviors increase when they are followed by reinforcement and decrease when they are followed by punishment. For example, newborns will change their rate of sucking on a pacifier, increasing or decreasing the rate of sucking, to hear a tape recording of their mother’s voice, a reinforcer (Moon, Cooper, & Fifer, 1993). Reinforcers are experienced as pleasurable. Infants (and people of all ages) change their behavior to experience reinforcement, in this example, changing the rate of sucking on a pacifier to hear the mother’s voice. Other research shows that newborns will change their rate of sucking to see visual designs or hear human voices that they find pleasing (Floccia, Christophe, & Bertoncini, 1997). Premature infants and even third-trimester fetuses can be operantly conditioned (Thoman & Ingersoll, 1993). For example, a 35-week-old fetus will change its rate of kicking in response to hearing the father talk against the mother’s abdomen (Dziewolska & Cautilli, 2006).

      As infants develop, they process information more quickly and require fewer trials pairing behavior and consequence to demonstrate operant conditioning. It requires about 200 trials for 2-day-old infants to learn to turn their heads in response to a nippleful of milk, but 3-month-old infants require about 40 trials, and 5-month-olds require less than 30 trials (Papousek, 1967). Infants’ early capacities for operant conditioning imply that they are active and responsive to their environments and adapt their behavior from birth.

      Imitation

      Toddler Tula puts a bowl on her head and pats it just as she watched her older sister do yesterday. Imitation is an important way in which children and adults learn. Can newborns imitate others? Believe it or not, some research suggests that newborns have a primitive ability to learn through imitation. In a classic study (see Figure 4.11), 2-day-old infants mimicked adult facial expressions, including sticking out the tongue, opening and closing the mouth, and sticking out the lower lip (Meltzoff & Moore, 1977). The prevalence and function of neonate imitation is debated (Suddendorf, Oostenbroek, Nielsen, & Slaughter, 2013). Some studies have failed to replicate this ability (Oostenbroek et al., 2016) and have suggested that tongue protruding simply reflects a general spontaneous newborn behavior (Keven & Akins, 2017), that it reflects arousal (Vincini, Jhang, Buder, & Gallagher, 2017), and that neonate imitation is not developmentally similar to later social imitation (Suddendorf et al., 2013). Others have confirmed that newborns from several ethnic groups and cultures display early capacities for imitation (Meltzoff & Kuhl, 1994; Nadel & Butterworth, 1999). In one study, newborns made corresponding mouth movements to both vowel and consonant vocal models; when the adult model made an a sound, newborns opened their mouths, and when the model made an m sound, newborns clutched their mouths (Chen, Striano, & Rakoczy, 2004). Studies that require infants to imitate several behaviors in response to different stimuli suggest that neonate imitation is not simply an arousal response (Nagy, Pilling, Orvos, & Molnar, 2013).

      Description

      Figure 4.11 Neonate Imitation

      In this classic experiment, Meltzoff and Moore demonstrated that neonates imitated the adults’ facial expression more often than chance, suggesting that they are capable of facial imitation—a groundbreaking finding.

      Source: Meltzoff and Moore (1977). Reprinted with permission of AAAS.

      Newborns mimic facial expressions, but they are simply carrying out an innate program thought to be controlled by the mirror neuron system, located in the premotor cortex (Binder et al., 2017). The mirror neuron system, an inborn capacity to make associations and respond to the actions of others by mirroring their actions in our own neural circuits, is apparent in both newborn humans and monkeys (Cook, Bird, Catmur, Press, & Heyes, 2014; Olsen, 2006; Shaw & Czekóová, 2013). The ability to copy others’ actions likely serves an evolutionarily adaptive purpose in humans, perhaps to aid the development of social communication (Tramacere, Pievani, & Ferrari, 2017). Newborns do not understand imitation; rather, the action of mirror neurons naturally syncs their body movements with the model. The regulatory mechanisms to inhibit imitative responding develop during infancy (Rizzolatti, Sinigaglia, & Anderson, 2008).

      In summary, infants enter the world equipped with several basic learning capacities that permit them to learn even before birth. Newborns display classical and operant conditioning, imitation, and habituation, illustrating that they are wired to attend to their environment. Not only do infants display early competencies that permit them to learn quickly but they are also surprisingly adept at sensing and perceiving stimuli around them.

      Thinking in Context 4.3

      Consider the developmental issue, nature and nurture, discussed in Chapter 1. From your perspective, do infants’ learning abilities reflect nature, inborn capacities, or nurture, capacities influenced by experience?

      Sensation and Perception During Infancy and Toddlerhood

      Meeting the pediatrician for the first time in her young life, newborn Kerry stared intently at the object the doctor held about 6 inches from her face. “I think she sees it!” said her surprised mother. “She most certainly does,” said the doctor. “Even as a newborn, your Kerry can sense the world better than you realize.” Newborns can see, hear, smell, taste, and respond to touch, but it is unclear how they perceive sensory stimuli.

      Developmental researchers draw a distinction between sensation and perception. Sensation occurs when our senses detect a stimulus. Our sense organs—the eyes, ears, tongue, nostrils, and skin—convert visual, auditory, taste, olfactory (smell), and tactile (touch) stimuli into electrical impulses that travel on sensory nerves to the brain where they are processed. Perception refers to the sense our brain makes of the stimulus and our awareness of it. The newborn is equipped with a full range of senses, ready to experience the world. They can both detect and perceive stimuli, but many of their abilities are immature relative to those of adults. Yet infants’ sensory abilities develop rapidly, achieving adult levels within the first year of life (Johnson & Hannon, 2015).

      Methods for Studying Infant Perception

      How do researchers study infant perception? The simplest method is through preferential looking tasks, experiments designed to determine whether infants prefer to look at one stimulus or another. For example, consider an array of black and white stripes. As shown in Figure 4.12, an array with more stripes (and therefore, many more narrow stripes) tends to appear gray rather than black and white because the pattern becomes more difficult to see as the stripes become more narrow. Researchers determine infants’ visual acuity, sharpness of vision or the ability to see, by comparing infants’ responses to stimuli with different frequencies of stripes because infants who are unable to detect the stripes lose interest in the stimulus and look away from it.

      Description

      Figure 4.12 Visual Acuity

      Researchers