Perception

The Senses begin to function early in life. But how can we actually know what an infant senses?

Since infants can’t tell us, researchers have devised ways to find out.

Example of a study… 1. A researcher presents two stimuli to an infant simultaneously. 2. The researcher monitors the infant’s eye movement. 3. If the infant looks more at one stimulus than the other, it is inferred that the infant prefers that stimulus over the other. 4. If accurate, measures of the eye movements can be made, this technique is quite simple and effective. The infants preference can be inferred because of habituation, a fancy word for boredom.

• Newborn visual acuity is 20/400 to 20/800 20/200 or worse defines legal blindness in adults • By 6 months, infant visual acuity is 20/25 • By 1 year, infant visual acuity is at adult levels (20/20)

(If you have 20/20 vision, you can see clearly at 20 feet what should normally be seen at that distance) https://www.allaboutvision.com/eye-exam/2020-vision.htm

What a Baby Sees in the First Year… Newborn to one month: • Has an inborn preference for what is familiar; • Pays attention briefly to the human face; • Responds to movement; • Possesses color vision, with the exception of blue.

What a Baby Sees in the First Year… Two months: • Visually "locks" onto a human face, particularly when the face is accompanied by a voice; • Watches people at a distance; • Is able to alternate his/her gaze between two people, objects or patterns, and show simple visual preference.

What a Baby Sees in the First Year… Four to six months:

• Is fascinated with faces of other babies and his/her own, as seen in a mirror; • Recognizes a person on sight and smiles selectively; • Shifts from his/her earlier preference for what is familiar to a preference for novelty. • At this time, there is evidence of more cognitive processing and visual recognition memory (i.e., recognizing relevant pattern information amidst change without being overtly distracted by detail). Also, a four- to sixth-month-old baby is visually guided in reaching/grasping; and visually inspects and examines a toy held in different orientations/positions, and looks for it when it falls from view.

What a Baby Sees in the First Year… Six to twelve months:

• At this age, objects continue to exist for a baby even when they are no longer in view; and he/she begins to recognize a novel picture as a representation of a familiar object. • In addition, social referencing is experienced at this age. At six to 12 months, the baby: • Can look in the direction that your eyes are gazing; • May modify his/her approach to, or withdrawal from, a novel situation by the positive (or negative) expression on a parent's face; • Begins to direct his/her gaze toward familiar people or objects, in response to common words when a parent labels what the baby is looking at; • Shows a toy to a parent in a manner of sharing wonder.

• Object perception is complex, it involves perceiving boundaries, shapes, sizes, and substances of objects

• Understanding object boundaries first requires recognizing where one object ends and another object or surface begins

Seeing Colours • At 1 week, the infant can discriminate the desaturated red from gray • At 2 months, the infant can discriminate the desaturated blue from gray • Newborns can perceive few colors, but by about 4 months newborns are able to see the full range of colors

Did the woman in this picture shrink? Or is she just farther away?

Seeing Depth & Movement • Objects and people in the environment move in many different ways (laterally, vertically, toward and away from the observer, and rotating) and at different speeds

• Moreover, infants’ own motion also contributes to motion perception. • Separate perception mechanisms may exist for different types of motion, nearly all of these mechanisms develop by about six months in healthy infants

https://www.youtube.com/watch?v=DrzmvI6iMrE

Perceiving Faces Infants are particularly interested in looking at human faces, but focus on different areas of the face depending on their age

Perceiving Faces • By 2 months of age, infants begin to attend to the internal features of the face – such as the nose and mouth • By 3 months of age, infants focus almost entirely on the interior of the face, particularly on the eyes and lips. At this age, infants can tell the difference between mother’s face and a stranger’s face. • Theorist’s believe that infants are attracted to human faces because faces have stimuli that move (eyes and lips) and stimuli with dark and light contrast (the eyes, lips and teeth).

Perceiving Faces • Infants are able to recognize familiar faces despite variations in expression and perspective • They also can discriminate gender in faces • Most infants show preferences for females; however, infants who are handled primarily by males express preference for male faces • By seven months, infants can discriminate an extensive range of the facial expressions, including happiness, anger, sadness, fear, and surprise, although it is unlikely that they understand the content of this range of emotions at this age

Signs of Eye and Vision Problems: • Excessive tearing - this may indicate blocked tear ducts • Red or encrusted eye lids - this could be a sign of an eye infection • Constant eye turning - this may signal a problem with eye muscle control • Extreme sensitivity to light - this may indicate an elevated pressure in the eye • Appearance of a white pupil - this may indicate the presence of an eye cancer

• Decorate the nursery in bright colors • and bold patterns. • Use a nightlight or other dim lamp in your baby's room. • • Keep reach-and-touch toys within your baby's focus, about eight to twelve inches. • • Talk to your baby as you walk around the room. • Give the baby plenty of time to play and explore on the floor.

Play hide and seek games with toys or your face to help the baby develop visual memory. Give the child building blocks and balls of all shapes and sizes to play with to boost fine motor skills and small muscle development. Give the child opportunities to take in a variety of sights—try the park, the zoo, or a walk through the neighborhood. When something catches his eye, give him time to inspect it thoroughly.

https://youtu.be/N9C9w8sDVLk

• The fetus can hear in utero at 7-8 months • While still inside the mother, the infant could hear many internal noises, such as the mother’s heartbeat, as well as many external noises including human voices, music and most other sounds • Your baby isn’t exposed to open air when she’s still growing inside you – there’s amniotic fluid surrounding her, plus all the layers of your body and their amniotic sac, between her and the world. So even when her ears are fully developed, the sounds she hears in utero are muffled…

Try this for fun (really!) Put your hand over your mouth. Have your partner do the same. Then carry on a conversation – and that’s what voices sound like to your baby in the womb. You’ll notice that although you can make out the tones and pitches of a sentence, you might not be able to understand some words. Similarly, try singing a song with your mouth covered and you’ll hear that the tune comes out loud and clear, but not the lyrics.

More facts about newborn hearing… • For unknown reason, newborns usually respond to a female’s voice over a male’s. This may explain why people will unknowingly raise the pitch of their voice when talking to newborns.

• The sound of other human voices, especially the mother’s, can have a calming or soothing effect on the newborn. Studies have shown that a fetus’s heart rate increases when she hears her mother’s voice, suggesting your baby becomes more alert when you speak. While most sound is transmitted through the air — and then through your uterus, when you speak, the sound of your voice reverberates through your bones and the rest of your body, amplifying it. So reading out loud, carrying on conversations and singing the songs you’ll be repeating to your baby over the coming years will help her to get to know your voice.

• Sudden sounds startle babies-making them cry, some rhythmic sounds, like a heartbeat/lullaby put a baby to sleep.

Playing Music during Pregnancy • Some experts believe amniotic fluid amplifies music while others claim the amplification only happens with low tones like that bass line that drives a song. When putting headphones on your belly, it is best to keep the music at or below 70 decibels when possible. (A normal conversation registers about 60dB) • The best type of music to play for baby is classical music because it tends to offer a range of notes and tends to repeat, creating an almost lullaby style sound in utero. • Also, if a pregnant woman loves classical music, playing music may soothe her more than the fetus. When a pregnant woman is more relaxed, she tends to feel less stress and that has a positive effect on the fetus. • Rap, heavy metal and some rock music tends to be discordant, loud and alarming.

Changes in hearing after birth… Newborn babies are able to hear, but adult levels of competence at discriminating a series of complex timbres, such as hearing differences in the way different musical instruments sound, are not reached until well into childhood

Languages • Researchers found that at 6 months, monolingual infants could discriminate between phonetic sounds, whether they were uttered in the language they were used to hearing or in another language not spoken in their homes. By 10 to 12 months, however, monolingual babies were no longer detecting sounds in the second language, only in the language they usually heard. • In contrast, bilingual infants followed a different developmental trajectory. At 6 to 9 months, they did not detect differences in phonetic sounds in either language, but when they were older — 10 to 12 months — they were able to discriminate sounds in both. • Even in the womb, she said, babies are exposed to the rhythms and sounds of language, and newborns have been shown to prefer languages rhythmically similar to the one they’ve heard during fetal development.

• Talking, reading, and singing to your baby helps build her personality, encourages language development, and promotes bonding • For babies who have trouble getting to sleep, turn on a white-noise machine; it's soothing because it replicates the low, steady sounds of the womb

https://youtu.be/hQm72CMAEf0

Hmmmmmm… How do the visual and auditory abilities of infants differ from those of elderly people? What similarities and differences do you notice? How well do infants and elderly people see objects closer than 6 inches, or objects that are very far away? How readily do infants and elderly people hear speech sounds?

Infants have a keen sense of smell and respond positively to pleasant smells and negatively to unpleasant smells… Honey, vanilla, strawberry, or chocolate: relaxed, produces a contented-looking facial expression Rotten eggs, fish, or ammonia produce exactly what you might expect… infants frown, grimace or turn away

Did you know…? Young infants recognize familiar odors and like the smell of their mother’s perfume!

• Use the same products regularly, because babies like familiarity • But nix heavily scented products while you're breastfeeding… Try to avoid scented detergents and heavy perfumes, because they can confuse your baby by masking the pheromones that you produce

• To build their sense of smell, expose babies to many scents • Tell them what each smell is and you’ll boost their language development too!

• Most infants seem to have a “sweet tooth”. For example, a newborn will choose to suck on a bottle of sweetened water, but will turn away or cry if given something bitter or sour to taste.

• However, at 4 months, infants will have a salty preference. • Taste preferences will continue to develop during the first year of life. • Studies show that a mother's diet can affect the way her breast milk tastes. These first flavors can help shape flavor preferences later on. For example, a mother who ate spicy foods while nursing is likely to have a child who grows up to favor spicy foods.

https://www.youtube.com/watch?v=Eha_eKrXNEY

• Eat a variety of foods while breastfeeding. • Starting around 6 months, introduce your baby to a variety of foods and flavors, this will give him/her a head start on experiencing the array of tastes found in a healthy diet. • Of course, if your family has a history of food allergies or if your baby has eczema, you should talk to your doctor before feeding him any new ingredients.

Newborns are sensitive to touch, many areas of the newborn’s body respond reflexively when touched

What do YOU think? If babies react to touch, do they experience pain?

OUCH!? • The infant’s nervous system is definitely capable of experiencing pain • Receptors for pain in the skin are just as plentiful in infants as they are in adults.

• Babies behavior in response to a pain-provoking stimulus suggests that they experience pain.

• Hold your baby often. • Skin-to-skin contact is especially therapeutic for newborns, doctors say. • Simply rubbing on some lotion after a bath is soothing, too, or you can try some gentle massage moves. • Let her/him feel different items on her skin, such as a soft stuffed animal or a bumpy ball. • When he/she’s older and more hands-on, give her/him toys of different shapes, sizes, and textures.

Assignment! You have been asked to design a toy that will be interesting for infants under the age of 6 months. Your toy should stimulate at least 2 of the baby’s senses. Brainstorm ideas with a partner. Then draw and describe your toy on chart paper. Finally, you will present your idea at the end of class.