Sensorimotor Learning and Severe Disability

1. Sensorimotor Learning and Severe Disability Chapter 10

2. Introduction • Making sense of the environment • Intrasensory integration - enhanced function in one sensory system • Intersensory integration - enhanced interaction between two or more sensory systems • Factors affecting intrasensory and intersensory integration

3. Organization of the Nervous System • Central nervous system – brain and spinal cord (CNS) • Peripheral nervous system – 12 pairs of cranial nerves, 12 pairs of spinal nerves and the autonomic nervous system • Neural impulses travel on dorsal and ventral tracts

4. Parts and Functions of the Spinal Cord • Tracts carry impulses to and from the brain • Each tract carries only one kind of sensory information and has a specific destination • Sensory information - afferent - dorsal ascending sensory tracts • Motor commands - efferent - ventral descending motor tracts

5. Parts and Functions of the Brain • Brain stem – regulates muscle and postural tone, reflexes, attention, arousal, wakefulness, and general activity • Midbrain – regulates postural reactions that enable stability and mobility in activities of daily living • Cerebellum – automatic performance of skilled movement so that conscious thought is not needed

6. Parts and Functions of the Brain • Cerebrum • Cerebral cortex - higher level mental functions; where sensory information is processed, integrated, or organized • Internal capsule • Limbic system - regulates emotion • Basal ganglia - enable steady postures and movement without tremors • Thalamus - relay station for sensory impulses

7. Cortical and Subcortical Disorders • Cortical disorders • Can be improved by conscious thought, practice, and determination • Responsive to ordinary teaching methods • Perceptual-motor intervention • Subcortical disorders • Do not respond to ordinary teaching methods • Sensoriomotor intervention

8. Cortical Functions • Functions of the cerebral cortex and the cortical tracts • Performs all higher-level functions • Help regulate excitation and inhibition processes • Cortical tracts carry impulses from one part of the brain to another

9. Subcortical Functions • Functions of all the CNS structures except the cerebral cortex and cortical tracts • Skilled movements - no conscious attention • Automatic movements like postural reactions and basic movement patterns • Common problems • Breakdown between cortical and subcortical • Problems in central processing

10. Muscle and Postural Tone • Muscle tone – contractile tension or firmness within a muscle or group of muscles • Postural tone – mobility and stability functional capacity of the total body • Holds the body upright against the pull of gravity • Antigravity muscles

11. Muscle Families and Actions • Extensor families – posterior surface • Flexor families – anterior surface • Adductor families – medial or inside surface and pull body parts toward or across midline • Abductor families – lateral or outside surface and pull body parts away from midline • Rotator muscle groups – inward rotators on anteromedial surface (work w/adductors) and outward rotators on posterolateral surface (work w/extensors)

12. Reciprocal Innervation or Inhibition • Neural process that regulates muscle and postural tone • Muscles on one surface contract while muscles on the opposite surface relax • Uppermotor neurons generate excitation and inhibition impulses

13. Muscle Tone Disorders • Hypotonia – floppiness • Hypertonia – stiffness, spasticity • Fluctuating tone – mixed cerebral palsy • Associated with both congenital and acquired conditions that cause severe damage to the motor part of the brain

14. Assessment of Muscle Tone Disorders • Observation, palpation, or EMG • Each part of body screened separately • Scoring system • 1 point - hypotonia • 2 points - normal muscle tone • +1 point - hypertonia

15. Hypotonia Intervention • Associated with severe disability • Delay achievement of motor milestones • Initiate little spontaneous, purposeful activity • Wheelchairs to help correct positioning and mobility • Major goal is to develop strength to use body parts in ADL

16. Hypertonia (Spasticity) Intervention • Inhibition or relaxation techniques used to decrease spasticity • Compromises postural reactions • Stretching exercises are essential to prevent contractures • Major goal is to independently perform stretches in good alignment

17. Sensory Input Systems • Sensory information must be organized and processed from all modalities • Touch and pressure Kinesthesis • Vestibular system Temperature • Pain Smell • Taste Vision • Audition • Common chemical sense

18. Tactile Integration • Most fully developed resource at birth • Light touch, deep pressure, cold, heat, pain • Tactile integration disorders • Tactile defensiveness • Tactile craving or aggressiveness • Body image and object awareness problems related to body boundaries

19. Assessment of Tactile Integration Problems • Tactile Defensiveness • Tactile Craving • Body Image and Object Awareness • Various problems

20. Activities for Intervention • Pairing touch with reward and gradually increasing the amount of touch • Pairing not touching with reward • Using rewards for improved awareness • Generalization • Various activities

21. Kinesthetic Integration • Muscle sense system • Contributes to movement awareness and coordination of body parts • Movement awareness problems with concepts of time, space, force, and flow • Receptors in every muscle, tendon, and joint • Noncortical kinesthetic integration • Cortical kinesthetic integration

22. Assessment of Kinesthetic Integration Problems • Observation in four areas before language • Reflex integration • Postural reaction emergence • Motor milestone achievement • Unsolicited, spontaneous imitations of movement • Observation after language • Imitate body movements on command • Do a movement, feel it kinesthetically, and then repeat it exactly after a period of time

23. Activities for Intervention • Repetition of movement • Movement targeted toward stationary points • Movement targeted toward moving object • Assisted and coactive movement • Extension activities • Movement exploration approaches • Minimize other input systems

24. Vestibular Integration • Helps to maintain static and dynamic balance • Equilibrium – biomechanical term denoting equal forces acting upon an object • Balance – the control processes that maintain body parts in the specific alignments necessary to achieve different kinds of mobility and stability • Vestibular, kinesthetic, tactile, and visual systems interact with environmental variables to enable balance • Vestibular apparatus

25. Assessment of Vestibular Integration • Challenges that cause momentary losses of balance - use of various playground apparatus • Natural activities that change head position • Vestibular activities spinning activities and nystagmus • Variety of activities that integrate tactile, kinesthetic, vestibular, and visual systems

26. Visual Integration • Various subsystems • Two types of vision • Refractive vision (acuity) • Orthoptic vision (eye coordination)

27. Refractive Vision (Acuity) • Visual acuity, the product of light rays bending and reaching the receptor cells (rods and cones) of the retina • Problems include myopia, hyperopia and astigmatism

28. Orthoptic Vision (Eye Coordination) • Six external muscles of the eyeball control movement • Binocular coordination – ability of two eyes to work in unison and fuse separate images into one, closely linked with balance and postural reactions • Depth perception - deriving meaning from visual space-time relationships • Problems include developmental delays in binocular coordination and depth perception, strabismus, and nystagmus

29. Assessment of Visual Integration • Observe students performing skills that require hand-eye and foot-eye coordination • Ophthalmologist – eye specialist • Refractive problems – treated by prescriptive glasses or surgery • Ophthalmic problems – some can be corrected with surgery, others may be associated with higher levels of visual processing

30. Activities for Intervention • Practice in many and varied movements • Complex process of integrating inputs and translating them into appropriate motor outputs • Variety of activites for intervention

31. Infant and Pathological Reflexes • Emphasis on pathological reflex-activity in adapted physical activity • Postures and patterns similar to those of infants are demonstrated by individuals with severe CP and TBI • Clumsiness or DCD is associated with failure to totally integrate reflexes

32. Infant Reflexes and Stereotypies • Involuntary, predictable muscle and postural tone shifts that are age-specific and important to typical development between birth and 9 months of age • Reflexes are building blocks for developing sensorimotor system - integrated about 9 months • Stereotypies are rhythmical movements of body parts that are performed over and over for no apparent reason - integrated about 12 months

33. Age-Appropriate Integration of Reflexes and Stereotypies • Integration - neural process of layering over, inhibiting, or suppressing reflexes and stereotypies • Occurs in various degrees - fatigue and stress conditions may cause breakdowns • Abnormal reflex activity is recognizable in clumsy movements

34. Pathological Reflexes • Reflexes that are not integrated at the developmentally appropriate times • Involuntary shifts of muscle tone, interfere with smooth, coordinated movement • Abnormal retention of reflexes contributes to the clumsiness associated with cerebral palsy

35. Reflexes Important in Physical Education REFLEX AVG. AGEMUSCLE TONE WATCH Tonic labyrinthine-prone 0-4 mon. Flexion Total body Tonic labyrinthine-supine 0-4 mon. Extension Total body Asymmetrical tonic neck 0-4 mon. Flex-Ext Arms Symmetrical tonic neck 6-8 mon. Flex-Ext Arms-Legs Moro 0-4 mon. Extension Arms-Hands Hand grasp 0-4 mon. Flexion Hands-Arms Foot grasp 0-9 mon. Flexion Toes, feet Extensor thrust 0-3 mon. Extension Legs Crossed extension 0-3 mon. Flex-Ext Legs Positive supporting-legs 3-8 mon. Extension Legs-trunk

36. Assessment Criteria for Physical Education Reflexes • Examine various aspects for each reflex • Tonic labyrinthine-prone reflex • Tonic labyrinthine-supine reflex • Asymmetrical tonic neck reflex • Symmetrical tonic neck reflex • Moro reflex • Hand grasp reflex • Foot grasp reflex • Extensor thrust reflex

37. Reflex Integration in Teaching • Explain movement errors in spite of corrective feedback • Student cannot override reflex patterns • Visual and auditory instructions alone are not effective

38. Principles of Reflex Integration • Maximize tactile, kinesthetic and vestibular input • Use total body movement patterns and games that inhibit reflexes • Increase practice time and time-on-task for correctly executed patterns • Intensify individual assistance so that patterns are performed correctly and pay particular attention to head position

39. Four Most Troublesome Reflexes • Reflexes initiated by head movements • Cannot move head without associated movements or muscle tone changes • TLR-prone - emphasize extension • TLR-supine - emphasize flexion • ATNR - emphasize head turn • STNR - emphasize head up or down

40. Overflow (Associated Movements) • Common indicator of clumsiness • Undesired reflex responses of body parts that should remain stationary • Caused by poorly integrated reflexes • Occur in childhood and generally disappear by adolescence • Many repetitions of correct movement

41. Postural Reactions • Automatic responses to sensory input that act to keep body parts in alignment, maintain equilibrium, and prevent injury • Some replace reflexes and others emerge to perform unique functions • Generally appear between 2 and 18 months • Generally persist throughout life

42. Assessment of Postural Reactions • Righting reactions - adjustments of the head or trunk • Parachute reactions - protective extension movements of the limbs • Equilibrium reactions - total body reponses • Assessment is completed by holding, tilting, and/or positioning child in specific ways

43. Righting Reactions • Automatic postural responses elicited by sensory input that signals that the head or trunk is not in midline • Head-in-space or Labyrinthine • Optical or visual • Landau reaction or body-in-sagittal plane righting • Body derotative (segmental rolling) • Body rotative (rise to stand)

44. Parachute or Propping Reactions • Protective extension movements of the limbs used to break or prevent a fall • Elicited by vestibular input, which signals a change in the movement of the head • Downward parachute • Sideward parachute • Forward parachute • Backward parachute

45. Equilibrium or Tilting Reactions • Total body responses that prevent falls • Appear between 5 and 18 months and remain throughout the lifespan • Initiated primarily by vestibular input • Assessment focuses on curve of the spine and position of the limbs • Absence or immaturity result in balance problems • Standing equilibrium involves stepping reactions

46. Activities for Intervention • Numerous trails to perform the same task over and over again • Positions used in testing are also used for intervention • Variety of apparatus and environments should be used to promote generalization

47. Overall Assessment Approach: Milani-Comparetti • Nonambulatory or ambulatory conditions • Protocol is easy to use and takes about 5 minutes • Developed for ages birth to 2 years, but frequently used with individuals of all age groups with severe body control problems • Scores on spontaneous behavior and evoked responses are recorded

48. Spontaneous Behaviors on the MC • Motor tasks in nine broad areas • Head control - four head positions • Body control - three body postures • Active movement - two active movement sequences

49. Evoked Responses • Five early reflexes • Hand grasp reflex • Asymmetrical tonic neck reflex • Moro reflex • Symmetrical tonic neck reflex • Foot grasp reflex • Three types of postural reactions • Righting • Parachute • Tilting or equilibrium

50. Pedagogy in Relation to Reflexes and Reactions • Physical education for young students with abnormal reflexes and balance problems is guided by the neurophysiological treatment approach of Bobath • Inhibition or suppression of abnormal reflex activity • Facilitation of righting, parachute, and equilibrium reactions in their proper developmental sequence