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9.3.2: The Newborn's Capabilities
Opening the book…
Learning Objectives
Identify and describe the distinct states of sleep and wakefulness.
Identify common neonatal reflexes.
Summarize newborn sensory capacities.
Explain the implications of research on prenatal learning for understanding early parent-child attachment.
Infant States
Newborns regulate their interactions with the world by cycling through distinct sleep and awake states. These states serve to balance stimulation, support development, and communicate needs. There are two primary sleep states—quiet sleep and active sleep—and four awake states: drowsy, quiet alert, active alert, and crying. Each state has unique characteristics and durations, shaping the infant's behavior and engagement.
Sleep
A newborn typically sleeps approximately 16-18 hours per 24-hour period, with half this time spent in active sleep and the other half in quiet sleep. The infant sleeps in several periods throughout the day and night, which means they wake up often throughout the day and night. (Salkind, 2005). 37
Active sleep, also known as rapid eye movement (REM) sleep, is a lighter sleep state in which the baby is more physically active. During active sleep, the infant may show facial twitches, brief limb movements, and irregular breathing, and their eyes may flutter under closed lids. This state is essential for brain development and processing sensory experiences, as it allows for the consolidation of what has been learned. Active sleep typically precedes wakefulness as part of the sleep-wake cycle.
Quiet Sleep
Quiet sleep, also known as non-rapid eye movement (NREM) sleep, is a restorative state characterized by deep sleep and minimal movement. In this state, newborns are less responsive to external stimuli, their breathing is slow and regular, and their facial expressions are relaxed. Quiet sleep is crucial for physical growth and brain development, as it enables the body to conserve energy and facilitates cellular repair.
Awake States
Drowsy
In the drowsy state, infants are transitioning between sleep and wakefulness. They may exhibit heavy-lidded eyes, slow movements, and irregular breathing patterns. This state often leads to either sleep or more alert behavior, depending on stimulation levels. Caregivers can use soothing techniques to help the baby drift into sleep from this state.
Quiet Alert
The quiet alert state is characterized by newborns being awake, calm, and most receptive to interaction. Their eyes are open and focused, breathing is steady, and movements are minimal. This is an ideal time for bonding and sensory engagement, as the infant is actively taking in their surroundings. Newborns spend 2 to 3 hours per day in this state.
Figure \(\PageIndex{2}\): Infants experience quiet alert phases where they are focused and calm, so that they may actively take in their surroundings. Image by Oss Leos on Pexels.
Active Alert
During the active alert state, infants are awake but more physically active and less focused. They may exhibit jerky movements, irregular breathing, and brief fussiness. This state often signals increasing stimulation or discomfort and may lead to crying if the infant’s needs are not addressed promptly.
Crying
Crying is the newborn’s primary means of communication and typically indicates a need for attention, such as hunger, discomfort, or the need for soothing. During crying episodes, infants exhibit increased activity, red or flushed faces, and rhythmic or escalating vocalizations. Crying is a highly stimulating state for both newborns and caregivers. On average, newborns spend about 1-2 hours per day crying, though this varies widely among infants, particularly during the first few weeks of life when "fussy periods" are common.
Reflexes
Newborns are equipped with several reflexes, which are involuntary movements triggered by stimulation. Some of the more common reflexes, such as the sucking reflex and the rooting reflex, are crucial for feeding. The grasping and stepping reflexes are eventually replaced with voluntary behaviors. Within the first few months of life, these reflexes disappear, while other reflexes, such as the eye-blink, swallowing, sneezing, gagging, and withdrawal reflex, stay with us as they continue to serve important functions. 39
Sensory Capacities
Throughout much of history, the newborn was considered a passive, disorganized being who possessed minimal abilities. However, current research techniques have demonstrated just how developed the newborn is, with especially organized sensory and perceptual abilities.
Vision
The womb is a dark environment void of visual stimulation. Consequently, vision is the most poorly developed sense at birth, and time is needed to build those neural pathways between the eye and the brain. Newborns typically cannot see further than 8 to 16 inches away from their faces, and their visual acuity is about 20/400, which means that an infant can see something at 20 feet that an adult with normal vision could see at 400 feet. Thus, the world probably looks blurry to young infants.
The infant’s sense of hearing is remarkably keen at birth, and the ability to hear is evident as early as the 7th month of prenatal development. In fact, an infant can distinguish between very similar sounds as early as one month after birth and can distinguish between a familiar and unfamiliar voice even earlier. Infants are particularly sensitive to the frequencies of sounds in human speech and tend to prefer the exaggeration of infant-directed speech, which will be discussed later. Newborns also prefer their mother’s voice over another female when speaking the same material (DeCasper & Fifer, 1980). Additionally, they will register in utero specific information heard from their mother’s voice. 41
Early Hearing
DeCasper and Spence (1986) tested 16 infants whose mothers had previously read to them prenatally. The mothers read several passages to their fetuses, including the first 28 paragraphs of The Cat in the Hat, beginning when they were 7 months pregnant. The fetuses had been exposed to the stories on average of 67 times, or 3.5 hours.
During the testing, the infants were able to choose between recordings of two stories, one of which was a story their mothers had read to them while they were in the womb, based on how fast they sucked on their pacifiers. They showed a preference for the stories their mothers read to them while they were in the womb. 42
Figure \(\PageIndex{4}\): A collection of children’s books. Image by kamiel79 on pixabay.
Touch and Pain
Immediately after birth, a newborn is sensitive to touch and temperature, and is also highly sensitive to pain, responding with crying and cardiovascular responses (Balaban & Reisenauer, 2013). Newborns who are circumcised, which is the surgical removal of the foreskin of the penis, without anesthesia experience pain as demonstrated by increased blood pressure, increased heart rate, decreased oxygen in the blood, and a surge of stress hormones (United States National Library of Medicine, 2016). Research has demonstrated that infants who were circumcised without anesthesia experienced more pain and fear during routine childhood vaccines. Fortunately, many circumcisions are now done with the use of local anesthetics.
Taste and Smell
Studies of taste and smell demonstrate that babies respond with different facial expressions, suggesting that certain preferences are innate. Newborns can distinguish between sour, bitter, sweet, and salty flavors and show a preference for sweet flavors. Newborns also prefer the smell of their mothers. An infant only 6 days old is significantly more likely to turn toward its own mother’s breast pad than to the breast pad of another baby’s mother (Porter, Makin, Davis, & Christensen, 1992), and within hours of birth an infant also shows a preference for the face of its own mother (Bushnell, 2001; Bushnell, Sai, & Mullin, 1989).
Infants seem to be born with the ability to perceive the world in an intermodal way; that is, through stimulation from more than one sensory modality. For example, infants who sucked on a pacifier with a smooth surface preferred looking at visual models of pacifiers with smooth surfaces. But those who were given a pacifier with a textured surface preferred to look at a visual model of a pacifier with a textured surface. 44
Figure \(\PageIndex{5}\): A baby sucking on a pacifier. Image by Beeki is licensed under CC0 1.0.
Balaban, M. T., & Reisenauer, A. E. (2013). Pain and touch. In M. H. Bornstein, T. Leventhal, & R. M. Lerner (Eds.), Handbook of child psychology and developmental science (7th ed., Vol. 4, pp. 94–128). Wiley.
Bushnell, I. W. R. (2001). Mother’s face recognition in newborn infants: Learning and memory. Infant and Child Development, 10(1–2), 67–74. https://doi.org/10.1002/icd.248
Bushnell, I. W. R., Sai, F., & Mullin, J. T. (1989). Neonatal recognition of the mother’s face. British Journal of Developmental Psychology, 7(1), 3–15. https://doi.org/10.1111/j.2044-835X.1989.tb00784.x
DeCasper, A. J., & Fifer, W. P. (1980). Of human bonding: Newborns prefer their mothers' voices. Science, 208(4448), 1174–1176. https://doi.org/10.1126/science.7375928
DeCasper, A. J., & Spence, M. J. (1986). Prenatal maternal speech influences newborns' perception of speech sounds. Infant Behavior and Development, 9(2), 133–150. https://doi.org/10.1016/0163-6383(86)90025-1
Porter, R. H., Makin, J. W., Davis, L. B., & Christensen, K. M. (1992). Breast odour as the only maternal stimulus elicits crawling towards the odour source. Developmental Psychobiology, 25(5), 511–518. https://doi.org/10.1002/dev.420250507
Salkind, N. J. (2005). An introduction to theories of human development. SAGE Publications.
