Chapter 4 Infancy: Sensation, Perception, and Learning
A New Babies reflexes
Reflex: humans involuntary response to external stimuli. One of the first
responses to appear. Survival benefits (not always known).
Abnormalities in reflexes can indicate visual, hearing problems. Neurological
problems are indicated by absent, unsusually strong or fail to disappear reflexes.
At birth doctors use these to test the central nervous system.
(table 41, pg 119).
Infant state: recurring pattern of arousal ranging from alert, vigorous, wakeful
activity to quiet, regular sleep.
They tell us that human behaviour is predictable from baby, humans are passive
and respond to their environments.
Studies suggest that state of arousal patterns start to form before birth.
on average sleeps 70% of the time. By 4w the baby takes less naps but sleep is
longer. By 8w baby is sleeping more at night than day.
Baby becomes less fussy as they gain more control over state.
Varies by culture. Kipsigis babies take more naps as they get older. Kenyan babies
take longer to sleep through the night. Kip. Parents sleep with babies, same with
other cultures. This can prevent risk factors of SIDS (sudden infant death
syndrome: death of a baby under 1(unexplained and spontaneous).
REM sleep: rapid eye momement slee. Rapid jerky movement of the eyes.
Dreaming. Babies spend 50% of sleep in REM as adults only spend 20%. Without
REM sleep ppl tend to become irritable.
Autostimulation theory: during REM sleep the infants brain stimulates itself,
which stimulates early development in the central nervous system.
(table 42, pg 121 Newborn infant states). (Figure 41, pg 121, infant sleep
Sudden infant death syndrome
most common between 2 and 4 months, rarelty occurs after 6m.
More likely in babies that already had problems or bad envir.
Apnea, choking, underdeveloped brain stem (controls breathing), nasal or
breathing blokages. Failure to transition smoothly from reflexive to voluntary
reflexes will put them at greater risk. Moniters can prevent SIDS but false alarms
place a lot of stress on parents. Babies shouldn’t sleep on soft matresses with
pillows, they should sleep on their backs. Co sleeping declines rates, however the
pediactic society does not recommend. o Crying
earliest means of communicating . Basic: hunger, among other factors, starts
arrhythmically at low intensity and gets louder and more rhythmic. Anger: the cry,
rest inhale vary in length, sgements of crying are longer, due to taking away toy or
pacifier. Pain: loud from the start, long cry, long silence (holding breathe)
followed by short gasping inhales. Caused by discomfort, or pain.
Mothers are better at determining what they want but is also correlated with how
much time father spends with baby.
Early months baby cries for physiological reasons. By 34 m they cry for
Some ppl say that attending to all crying may increase crying in future, others say
that knowledge of the parents being dependable decreasing crying. Others even
suggest that only distress cries should result in attention.
Crying can be a tool altering abnormalities in development. (e.g. colic: prolonged
unexplained crying in infant (20% of infants 24w of age). It is harmless, however
may indicate hernia or ear infection. It is a high pitched, urgent, piercing cry.
How to Soothe an Infant
o Infants abilities to soothe themselves
sucking, it reduces babies distress, sucking on certain things are more effective
than others. Eye contact from parent increased effects in 4w old.
By 4 w the infant relies on caregiver to soothe them.
o How parents soothe their babies
pacifier, rocking, massaging, swaddling,
other cultures see (box 4.2)
Evaluating the Newborns Health and Consequences
Brazelton Neonatal Assessment Scale: used to measure an infants sensory and
perceptual capabilities, motor development, range of states, ability to regulate
these states. Also indicate whether brain and central nervous system are properly
regulating autonomic responsivity. It is used to see any risks of infant
developmental problems or neurological impairment. Cross culturallty indicates
parent child interactions. Infants motor abilities are influnecd by cultural
practices and routines.
How cultures affect crying and soothability
some cultures, swaddle, others carry them on their body. Some put their child on a
cradleboard. Each culture cries and is soothed in different ways, however it could
just be associated with the genes linked to that culture.
The Infants sensory and Perceptual Capaities
Sensations: detection of stimuli by sensory receptors.
Perception: interpretation of sensations in order to make meaningful. Babies sensory and perceptual systems may be biologicallt prepared to process
and respond to social stimuli. This prep is adaptive.
Unlocking the secrets of babies sensory capabilities
reseaerchers rely on autonomic nervous system (involuntary bodily fucntions;
heart rate, breathing). Or motor responses which give cues about sensory ability
(e.g. burn> leg kick).
Measuring sucking patterns. Uses violationofexpectation method. If baby is
shown an impossible event and the babies sucking rate slows or stops you ca
conclude that the baby is responding to an event that is different.
Visual performance method: preferred by frantz. Measure the length of time they
spend attending to different stimuli
Habituation does occur: the process by which an ind. Reacts with less and less
intensity to a repeatedly presented stimuli, eventually responding faintly or not at
Hearing: babies are good listeners
newborns hearing is extremely developed and can be measured from birth
even before birth they may hear sounds or vibrations in the uterus.
Sound must be louder for a newborn, they are less sensitive to low pitch,
Motherese: more likely to capture babies attention.
Audoitory localization: ability to determine from where in space a sound is
originating. Babies are good at this. Can also discriminate between approaching
and not, and slow and fast.
Babies are sensitive to melody changing.
In early stages babies can infants are equally edept ar processing either scale type,
depending on their culture they become better at one.
Infants listening to music does not increase their intelligence (based on research).
Babies 2 years old prefer human voice over other noise.
47 months prefer infant directed play songs and lullabies. They have increased
arousal when mom sings.
Vision: how babies see their worlds
newborns can detect changes in brightness, movement, and follow object with
o The clarity of infants vision
visual acuity: sharpness of vision; the clarity with which fine details can be
At 1 month babies vision is 20/200 20/800. By 6m to a year it is at normal adult
Testing: how sensitive a baby is to visual detail such as width or densisty of a se