LANGUAGE & COGNITION

LANGUAGE & COGNITION

Motor Development

Motor development occurs in an orderly sequence as infants move from

reflexive reactions (e.g., sucking and rooting) to more advanced motor functioning. As

mentioned during the prenatal section, development occurs according to the

Cephalocaudal ( from head to tail) and Proximodistal ( from the midline outward)

principles. For instance, babies first learn to hold their heads up, then to sit with

assistance, then to sit unassisted, followed later by crawling, pulling up, cruising or

weeks and 4 months old. On average, most babies sit alone at 7 months. Sitting

involves both coordination and muscle strength, and 90% of babies achieve this

milestone between 5 and 9 months old. If the child is displaying delays on several

milestones, that is reason for concern, and the parent or caregiver should check in

with the child’s pediatrician. Developmental delays can be identified and addressed

through early intervention.

Motor Skills refer to our ability to move our bodies and manipulate objects.

Gross motor skills focus on large muscle groups that control our head, torso, arms and

legs and involve larger movements (e.g., balancing, running, and jumping). These

skills begin to develop first. Examples include moving to bring the chin up when lying

than in the legs. Fine motor skills focus on the muscles in our fingers, toes, and eyes,

and enable coordination of small actions (e.g., grasping a toy, writing with a pencil,

and using a spoon). Newborns cannot grasp objects voluntarily but do wave their arms

toward objects of interest. At about 4 months of age, the infant is able to reach for an

object, first with both arms and within a few weeks, with only one arm. At this age

grasping an object involves the use of the fingers and palm, but no thumbs. This is

known as the Palmer Grasp. The use of the thumb comes at about 9 months of age

when the infant is able to grasp an object using the forefinger and thumb. Now the

infant uses a Pincer Grasp, and this ability greatly enhances the ability to control and

manipulate an object. Infants take great delight in this newfound ability. They may

spend hours picking up small objects from the floor and placing them in containers. By

9 months, an infant can also watch a moving object, reach for it as it approaches, and

(Shaffer, 1985). 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 one of the most poorly developed senses at birth, and time is

needed to build neural pathways between the eyes and the brain (American

Optometric Association [AOA], 2019). Newborns typically cannot see further than 8 to

means an object 20 feet away from an infant has the same clarity as an object 300

feet away from an adult with normal vision. By 3-months visual acuity has sharpened

to 20/200, which would allow them the see the letter E at the top of a standard eye

not fully grown. Can babies see color? Young infants can perceive color, but the colors

need to be very pure forms of basic colors, such as vivid red or green rather than

weaker pastel shades. Most studies report that babies can see the full spectrum of

colors by five months of age (AOA, 2019).

Newborn infants prefer and orient to face-like stimuli more than they do other

patterned stimuli (Farroni et al., 2005). They also prefer images of faces that are

upright and not scrambled (Chien, 2011). Infants also quickly learn to distinguish the

face of their mother from faces of other women (Bartrip, Morton, & De Schonen, 2001).

When viewing a person’s face, one-month olds fixate on the outer edges of the face

rather than the eyes, nose, or mouth, but two-month olds gaze more at the inner

features, especially the eyes (Hainline, 1978). Researchers have examined the

movements. Aslin also found that eye movements lag behind an object’s motion.

This means young infants do not anticipate the trajectory of the object. By two

months of age, their eye movements are becoming smoother, but they still lag

behind the motion of the object and will not achieve this until about three to four

months of age (Johnson & deHaan, 2015).

Newborns also orient more to the visual field toward the side of the head, than to

the visual field on either side of the nose (Lewis, Maurer, & Milewski, 1979). By

two to three months, stimuli in both fields are now attended to equally (Johnson &

deHaan, 2015).

Binocular vision, which requires input from both eyes, is evident around the

hear is evidenced as soon as the seventh month of prenatal development. Newborns

prefer their mother’s voices over another female even if speaking the same material

(DeCasper & Fifer, 1980). Additionally, they will register in utero specific information

heard from their mother’s voice. DeCasper and Spence (1986) tested 16 infants

(average age of 55.8 hours) 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 an average of 67 times or 3.5 hours. When the

experimental infants were tested, the target stories (previously heard) were more

reinforcing than the novel story as measured by their rate of sucking. However, for

control infants, the target stories were not more reinforcing than the novel story

indicating that the experimental infants had heard them before. An infant can

Cutler, & Redanz, 1993). Their ability to distinguish the sounds that are not in the

language around them diminishes rapidly (Cheour-Luhtanen, et al., 1995).

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

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). Intermodality. 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 either a smooth or textured surface preferred to look at a

corresponding (smooth or textured) visual model of the pacifier. By 4 months, infants

can match lip movements with speech sounds and can match other audiovisual

events. Sensory processes are certainly affected by the infant’s developing motor

abilities (Hyvärinen, Walthes, Jacob, Nottingham Chapin, & Leonhardt, 2014).

Reaching, crawling, and other actions allow the infant to see, touch, and organize his

rate of sucking to a pacifier equipped with transducers that measure muscle

contractions. Next, an auditory stimulus is presented, such as a human voice uttering

a speech sound such as “da.” The rate of sucking will typically increase with the new

sound, but then decrease to baseline levels as “da” is repeatedly presented, showing

habituation. If the sound “ma” was then presented, the rate of sucking would again

increase, demonstrating that the infant can discriminate between these two stimuli.

Additionally, the speed or efficiency with which infants show habituation has

been shown to predict outcomes in behaviors, such as language acquisition and verbal

and nonverbal intelligence. Infants who show difficulty during habituation, or habituate

at slower than normal rates, have been found to be at an increased risk for significant