1. Copyright © 2005 Pearson Education Canada Inc.5-1 Chapter 5: Physical Development in Infants and Toddlers 5.1 Healthy Growth 5.2 The Developing Nervous System 5.3 Motor Development 5.4 Sensory and Perceptual Processes

2. Copyright © 2005 Pearson Education Canada Inc.5-2 5.1 Healthy Growth Features of Human Growth Variations on the Average Profile Mechanisms of Physical Growth Challenges to Healthy Growth

3. Copyright © 2005 Pearson Education Canada Inc.5-3 Features of Human Growth Follows the cephalocaudal principle Muscles become longer and thicker During the first year, a layer of fat is added Cartilage is replaced by bone

4. Copyright © 2005 Pearson Education Canada Inc.5-4 Variations on the Average Profile Secular Growth Trends: generational changes in physical development Average and normal are not the same

5. Copyright © 2005 Pearson Education Canada Inc.5-5 Average Height and Weight

6. Copyright © 2005 Pearson Education Canada Inc.5-6 Mechanisms of Physical Growth Heredity influences adult height The pituitary gland secretes growth hormone Nutrition is particularly important during infancy when growth is rapid At 2 years, growth slows and kids become “picky” eaters

7. Copyright © 2005 Pearson Education Canada Inc.5-7 Challenges to Healthy Growth Malnutrition is especially damaging in infancy Malnutrition needs to be treated with adequate diet and parent education Many diseases that kill young children are preventable with vaccines, improved health care, and changing habits

8. Copyright © 2005 Pearson Education Canada Inc.5-8 5.2 The Developing Nervous System Organization of the Mature Brain The Developing Brain

9. Copyright © 2005 Pearson Education Canada Inc.5-9 Organization of the Mature Brain Neuron: basic unit of nervous system Cerebral hemispheres: right and left halves of the cortex Frontal cortex: area of the cortex that controls personality and the ability to carry out plans

10. Copyright © 2005 Pearson Education Canada Inc.5-10 The Neuron

11. Copyright © 2005 Pearson Education Canada Inc.5-11 Organization of the Brain Source: Ghim, 1990

12. Copyright © 2005 Pearson Education Canada Inc.5-12 The Developing Brain Brain originates in neural plate Brain regions specialize early (e.g., left hemisphere for verbal functioning; frontal cortex for emotion) “Flexible” brain organization shown by children who recover from brain damage.

13. Copyright © 2005 Pearson Education Canada Inc.5-13 5.3 Motor Development The Infant’s Reflexes Locomotion Fine Motor Skills Maturation, Experience, and Motor Skill

14. Copyright © 2005 Pearson Education Canada Inc.5-14 The Infant’s Reflexes Newborns’ reflexes prepare them to interact with the world Some reflexes are important to survival (e.g., rooting and sucking) Some protect the newborn (e.g., blink and withdrawal) Some are foundations for later motor behaviour

15. Copyright © 2005 Pearson Education Canada Inc.5-15 Locomotion Dynamic Systems Theory: motor development involves many distinct skills Differentiation and integration of component skills (posture and balance, stepping, perceptual skill) is necessary

16. Copyright © 2005 Pearson Education Canada Inc.5-16 Development of Locomotion Source: Based on Shirley, 1931, and Bayley, 1969

17. Copyright © 2005 Pearson Education Canada Inc.5-17 Fine Motor Skills Reaching and grasping becomes more coordinated throughout infancy. Toddlers prefer to use one hand and this preference becomes stronger during the preschool years.

18. Copyright © 2005 Pearson Education Canada Inc.5-18 Maturation, Experience, and Motor Skill Maturation is important: Studies of Hopi infants. Experience matters, too: African infants and training studies

19. Copyright © 2005 Pearson Education Canada Inc.5-19 5.4 Sensory and Perceptual Processes Smell, Taste, and Touch Hearing Seeing Integrating Sensory Information

20. Copyright © 2005 Pearson Education Canada Inc.5-20 Smell, Taste, and Touch Even newborns can smell, taste, and feel These skills are useful in recognizing parents and in feeding

21. Copyright © 2005 Pearson Education Canada Inc.5-21 Hearing Infants hear well, though not quite as accurately as adults Infants’ hearing is best for sounds that have pitches in the range of human speech Infants use sound to locate objects

22. Copyright © 2005 Pearson Education Canada Inc.5-22 Seeing Acuity is 20/400 at birth but improves rapidly Infants perceive colours by 3 or 4 months Infants master perceptual constancies early Many cues are used to infer depth Edges & motion are used to perceive objects

23. Copyright © 2005 Pearson Education Canada Inc.5-23 Wavelength of Light

24. Copyright © 2005 Pearson Education Canada Inc.5-24 Shape Constancy

25. Copyright © 2005 Pearson Education Canada Inc.5-25 Perception of Objects

26. Copyright © 2005 Pearson Education Canada Inc.5-26 Use of Motion to Perceive Objects

27. Copyright © 2005 Pearson Education Canada Inc.5-27 Infants’ Scanning of Faces

28. Copyright © 2005 Pearson Education Canada Inc.5-28 Face-like Stimuli Source: Morton & Johnston, 1990

29. Copyright © 2005 Pearson Education Canada Inc.5-29 Integrating Sensory Information By 1 month, can integrate sight and touch By 4 months, can integrate sight and sound 4- and 7-month-olds can match facial appearance (boy or man) with sound of voice

30. Copyright © 2005 Pearson Education Canada Inc.5-30 Infant Watching Videos

31. Copyright © 2005 Pearson Education Canada Inc.5-31 Time Spent Looking at Videos