Chapter 4- Motor Development

Chapter 4: Early Motor Development

Page 1: Introduction

  • Definition of early motor development


Page 2: Early Motor Behavior

  • Spontaneous Movements:

    • Not caused by known external stimuli.

  • Reflexive Movements:

    • Stereotypical responses triggered by specific stimuli.


Page 3: Spontaneous Movements

  • Function as building blocks for voluntary movements.

  • Examples:

    • Spontaneous arm movements (resembling reaching).

    • Spontaneous kicking (similar to walking).


Page 4: Supine Kicking and Walking

  • Phases Involved:

    1. Flexion Phase:

      • From an extended position to hip and knee flexing, continuing until fully flexed (pause).

    2. Extension Phase:

      • Extension begins with knee extension leading to ankle plantarflexing (toe pointing).


Page 5: Infantile Reflexes

  • Occur rapidly after stimulus onset.

  • Involves single muscles or muscle groups (not whole-body response).

  • Persistence of reflexes past normal age may indicate neurological issues.


Page 6: Purposes of Reflexes

  • Built-in responses facilitate survival and adaptability.

  • Enable a 'dialogue' with the environment.

  • Reflexive movements lead to sensory consequences promoting adaptation.

  • Serve as foundational building blocks for future voluntary movements.


Page 7: Types of Reflexes

  1. Primitive Reflexes:

    • Essential for survival.

  2. Postural Reactions:

    • Assist in maintaining upright posture amidst environmental changes.

  3. Locomotor Reflexes:

    • Involves moving in place.


Page 8: Table of Reflexes

  • Primitive Reflexes:

    • Asymmetrical Tonic Neck Reflex: Supine, head turn extends same-side limb.

    • Palmar grasping: Tight grasp upon palm touch.

    • Moro Reflex: Arms/legs extend and flex when startle response occurs.

    • Others outlined include Babinski, Sucking, and Searching reflexes.


Page 9: Asymmetrical Tonic Neck Reflex

  • Triggered by turning the head to one side while in supine position.

  • Result: Same-side extension of arm and leg.


Page 10: Postural Reactions

  • Arise around 2 - 4 months of age.

  • Initially reflexive but become integrated into general movement repertoire.


Page 11: Postural Reaction Examples

  • Derotative Righting:

    • Supine position, legs turn to one side, trunk and head follow.

  • Labyrinthine righting:

    • Supported upright, tilting leads to head adjustments.


Page 12: Labyrinthine Righting Reflex

  • Position: Supported upright.

  • Response: Head moves to maintain an upright position.


Page 13: Locomotor Reflexes

  1. Crawling:

    • Pressure to foot induces crawling pattern (0 - 4 months).

  2. Stepping:

    • Placing feet on surface triggers walking pattern (0 - 5 months).

  3. Swimming:

    • Initiated when placed in water (11 days - 5 months).


Page 14: Stepping Reflex

  • Triggered by soles on flat surface, resulting in legs moving in walking pattern.


Page 15: Reflexes to Voluntary Movement

  • Role of constraints causing the stepping reflex to disappear.

  • Examples of re-emergence in specific environments (ankle weights, water).


Page 16: Motor Milestones

  • Fundamental motor skills:

    • Building blocks for more complex skills; they are cumulative and sequential.


Pages 17 - 19: Motor Milestones (Specific Ages)

  • Milestones include lifting head, rolling, sitting, standing, and walking, with average ages for reaching these milestones detailed.

  • Illustrated with comparative developmental timelines (e.g., typical vs. delays).


Page 20: Rate Limiters in Motor Skill Acquisition

  • Individual constraints that can inhibit motor skill attainment.

  • Cultural norms influence social interactions and parenting practices.


Page 21: Postural Control and Balance

  • Involves the integration of sensory information and motor responses.

  • Continuous adaptation of sensory-motor responses in infants.


Page 22: Summary and Synthesis

  • Reflex appearance and disappearance is part of typical development.

  • Milestones follow a predictable sequence but can vary individually.


Page 23: Test Your Knowledge

  • Discussion points regarding individual, environmental, and task constraints affecting motor milestones.


Page 24: Atypical Development

  • Importance of professional screening for neurological health based on mobility delays.


Page 25: Preterm Infants

  • Infants born early face risks of complications related to gestational age and weight.


Page 26: Definitions of Preterm and Low Birth Weight

  • Classifications based on gestational weeks and birth weight.


Page 27: Short-term Health Complications

  • Risk of lung immaturity and brain injury in low birth weight infants.

  • Use of corticosteroids for prevention.


Page 28: Potential Long-term Outcomes

  • Risks associated with motor disorders linked to brain injury; variability based on developmental interactions.


Page 29: Outcomes in Infancy

  • Statistical data on motor and cognitive delays in comparison to gestational age and birth weight.


Page 30: Motor Development in Infancy

  • Describes hypotonicity and its implications on motor skill development especially in preterm infants.


Page 31: Motor Development - Walking

  • Observations that preterm infants may take more steps earlier compared to full-term infants of the same age.


Page 32: Environmental Influences

  • Discussion of how the environment affects brain and motor development in preterm infants in NICU settings.


Page 33: Key Points on Preterm Development

  • Highlights the variability and influencing factors on development in relation to early birth.


Page 34: Cerebral Palsy

  • Description of non-progressive motor disorders from early childhood onset and resulting in movement or posture complications.


Page 35: Severity of Cerebral Palsy

  • Classes based on severity: mild, moderate, severe.


Page 36: Motor Types in Cerebral Palsy

  • Description of conditions like spasticity, ataxia, and hypotonia among others.


Page 37: Classification by Body Part

  • Terms include monoplegia, hemiplegia, paraplegia, tetraplegia, and diplegia.


Page 38: Motion Disability Types

  • Identification of various types of motor difficulties resulting from cerebral palsy.


Page 39: Development from 0 – 12 Months

  • Descriptions of movement and control issues at different intervals of infancy.


Page 40: Down Syndrome

  • Overview of intellectual and developmental disabilities.

  • Delays in language and motor skills development.


Page 41: Down Syndrome Milestones

  • Milestones for motor skills and language compared with typical development.


Page 42: Baby Treadmills

  • References the use of treadmills for infant motor development studies.


Page 43: Autism Spectrum Disorders

  • Diagnostic criteria based on social communication deficits and restricted interests.


Page 44: Progressive Delays in Motor Development

  • Observations of motor delays beginning as early as 6 months, impacting engagement.


Page 45: Baby Siblings Observations at 6 Months

  • Increased head lag and decreased activity noted in younger siblings of children with ASD.


Page 46: ASD Early Motor Development

  • Documentation of critical development point between 14 to 24 months and its relation to motor delays.


Page 47: Early Trajectories

  • Classification of developmental tracks from accelerated to delayed pathways in motor development.


Page 48: Summary of Developmental Paths

  • Overview of the percentages of developmental paths among children from 6 to 36 months.