Sleep wake states:
- Synchronization of cyclic motor activity with HR and REM occurs by 28 weeks gestation.
- Distinct active sleep (AS) & quiet sleep (QS) states present by 27-30 weeks gestation.
- More AS earlier in development.
- Less QS earlier in development.
- Patterns of AS – QS brain activity change in utero and postnatally.
Sleep wake regulation:
- Circadian pacemaker located in anterior hypothalamus, very sensitive to light.
- Not present as newborn; emerges at 5-6 weeks after birth.
- Diurnal sleep first seen at 12 weeks.
- Circadian rhythm well developed by 4-13 months.
Sleep wake effect on brain maturation:
- AS favors maturation of brain, induces CNS development in fetus and newborn.
- AS = intense, endogenous generalized neuronal firing, retinas, and visual system.
- QS stimulates synaptogenesis.
- Information acquired during wakefulness is processed during QS.
- QS enables cortical plasticity.
Tactile sensory responses:
- Fetal tactile response by 2-4 months gestation.
- Cutaneous sensitivity to touch developed by 28 weeks, increases greatly first 5 days after birth.
- Tactile stimulation is generally pleasurable –cuddling, rocking, stroking, massage.
- Sensitive tactile areas – mouth, lips, fingers, hands, toes, feet.
- Sucking = pleasurable tactile, stimulation of mouth and lips…
- major method of calming and soothing.
- Newborn’s taste is keener than adults.
- Laryngeal taste receptors can distinguish autologous from heterologous milk.
- Taste preferences:
- Sweeter breast milk produces greater suck and milk consumption.
- Bitter or salty taste decreases sucking.
- Newborns smell and recognize mother by 6 days age.
Vestibular sensitivity present at birth:
- Rotation and acceleration produce nystagmus.
- Newborns are soothed by carrying rocking, jiggling.
- Upright posture (being picked up to shoulder) is more soothing than contact per se.
- Briefly soothes hungry infant and arouses sleepy infant.
- Increase visual attention in alert infant.
Carrying of baby provides to infant:
- Postural change, repetitiveness, constancy.
- Rhythmicity, proximity to mother, increases sensory stimulation.
- Increases maternal responsiveness.
- Decreases maternal response time.
- Anticipates infant behavioral deterioration.
Good maternal care =
- Positive sensory experience with vestibular stimulation.
- Picking-up and holding.
- Moving or carrying.
- Soothing promotes visual alerting and visual exploration.
- Nursing and feeding promotes a calm, awake-alert state afterwards.
Newborn Visual preferences:
- Light – dark contrast, patterns
- Black and white
- Human face (mother’s own)
- Cool colors – blue, green, purple
- Picture or drawing of face
- Warm colors – red, yellow, orange
- Bull’s eye
- Variety of shapes, orientations, and colors
- Myopic initially with visual acuity 7-12 inches
- Organized visual perception present at birth, unlearned, innate.
- Infant distressed by altered or scrambled maternal face (mask, glasses).
- Newborn predisposition of response to faces.
- Adaptive in giving social orientation to others.
- Mutual visual regard = critical in maternal infant attachment.
- Mother aligns herself en-face with infant.
- Eye contact = love.
- No eye contract = rejection.
- Mother’s nodding, smiling face elicits social smile.
- Eye contact, fixing and following (tracking) present at birth.
- Well developed at 1-2 months.
- Recognizes parents at 2-3 months.
- Visual imitative behavior = sticks out tongue, opens mouth, protrudes lips.
- Expresses visual interest as baby becomes quiet and still, face brightens and eyes glisten, pupils dilate and HR decelerates.
Newborn Sound preferences:
- Mother’s own voice.
- Newborns can discriminate their mother’s voice & will work to produce it by sucking on nipple.
- Female voice (higher pitch than male).
- Voice inflections (over monotone).
- Exaggerated variations and articulations in sentences and speech (“baby talk”).
- Variety of sounds.
Newborn auditory competency:
- Hearing fosters language acquisition.
- Newborns must hear voices and speech (rhythm and style) in order to develop language.
- Voices & speech convey security to newborn.
- Newborns must hear themselves make sounds.
- Variable infant sounds
- Cooing, babbling, gurgling, slurping by 2 months.
- Giggling, squealing, laughing by 4 months.
- Cry is the primary modality of signaling.
- Hunger, pain, discomfort, fatigue, loneliness.
Newborns have four audibly different and spectrographically different cries
- Newborn cry engenders discomfort in mother and urge to “do something”.
- Maternal response to cry is differential and selective.
- Contingent behavior = mother rewarded by her success in diminishing crying.
- Newborn cry = 100 dB intensity level, quite noxious to adults.