1. Sensory Receptors in Sensory Motor
Approaches to Treatment
Presented By:
kahindi kazungu Ruwa

2. Introduction
Sensory information is critical in the initiation
and correct performance of both voluntary and
involuntary motor responses, (Pedretti 2001).

3. Sensory receptors
• Body contains sensory receptors (end
organs) that provide information about
changes in environment.
• They are therapeutic portal where stimuli can
be put in nervous system.
• 3 categories based on sensory therapy.
• Interoceptors, exteroceptors, proprioceptors,
(McCormack 2001).

4. Interoceptors
• Monitor events within the body.
• Located within walls of respiratory,
cardiovascular, gastrointestinal and
genitourinary systems.
• Detect stimuli like distention of cavity wall,
monitor PH level of blood.

5. Cont.
• Examples; baroreceptors in carotid sinus and
mucous membranes of oral cavity, (Feuchter
2001).

6. Occupational therapy use of
interoceptors
• Oral stimulation for activities of daily living
in feeding.
• Stimulation and vibration to facilitate
destrusor muscles or inhibit micturition.
• Reduce hypertonicity in skeletal muscles.
• Reduce tactile defensiveness in children,
(Lowenstein 1991).

7. Exteroceptors
• Located under skin in external mucous
membranes and special senses.
• Respond to stimuli arising outside the body.
• They are five subtypes; free nerve endings,
hair end organs, meissner corpuscles, pacinian
corpuscles, markel tactile disks, (Pedretti
2001).

8. Free nerve endings
• Located in subcutaneous tissues
• Unencapsulated unmyelinated projections for
sensory detection.
• Widely distributed in skin and viscera.
• Therapeutically, activated with thermal or
brushing.
• Stimulation causes arousal
• Icing and rubbing over skin alleviates pain.

9. Hair end organs
• Located at base of hair follicle.
• Activated by bending or displacing hair.
• In therapy, stimulated during light touch or
stroking of skin, (Feuchter 2001).

10. Meissner corpuscles
• Elongated encapsulated end organs.
• Located beneath epidermis in hairless skin.
• Plenty in fingertips, tip of tongue, lips, pads of
feet.
• Responsible for fine tactile discrimination.
• Respond to low frequency, (Feuchter 2001).

11. Pacinian corpuscles
• Large encapsulated receptors (rice grain).
• Located in deep skin layers, viscera,
mesenteries, ligaments, blood vessels,
periosteum of long bones.
• Also found on lateral margin of digits.

12. Cont.
• Respond to deep pressure like in high
frequency vibration.
• Plenty in hands, soles of feet and mesentery
hence excellent area for stimulation.

13. Markel tactile disks
• Non encapsulated receptors located in deeper
layer of epidermis in hairless skin.
• In abundance in volar surface of fingers, lips
and external genitalia.
• Sensitive to slow movements across skin
surface.
• Responsible for tickle and pleasure touch
sensation, (Pedretti 2001).

14. Proprioceptors
• Monitor awareness of position in space,
posture, movement and equilibrium reactions.
• Located in tendons, muscles and joints.
• Proprioception can be conscious
(kinesioceptors) joint receptors, or

15. Cont.
• Subconscious pertaining to muscle spindles,
Golgi tendon organs and vestibular apparatus,
(McCormack 2001).

16. Muscle spindles
• Complex encapsulated receptors located deep
within skeletal muscles.
• Monitor changes in length of muscle and rate
at change in length.
• Slender in structure.

17. Cont.
• House 4-6 bundles of specialized muscle
fibres called intrafusal fibres.
• Primary spinal level reflex associated with
muscle spindle is reciprocal innervation.

18. Golgi tendon organs
• Spindle- shaped, located in musculotendious
region of proximal and distal insertions.
• Monitor tendon tension and force produced by
muscle contraction.
• Associated with autogenic inhibition.

19. Cont.
• Cause inhibition of primary muscle contracted
against gravity.
• Used to inhibit spasticity in adductors,
superficial flexors, (McCormack 2001).

20. Cont.
• Basic stretch reflex, when one muscle group is
facilitated,
• The opposite muscle is inhibited.
• A relationship called reciprocal inhibition.
• Therapist uses reflex function of muscle
spindle in;
• quick stretch, vibration and tapping over
muscle belly, (Feuchter 2001).

21. Factors affecting muscle spindles
• Persons’ emotional state
• Pain syndrome
• Cold environment
• Excessive auditory stimulation
• Distension in bowel or bladder
• Medications such as muscle relaxants

22. kinesioceptors
• Located in joint capsules, ligaments and
tendons.
• Ruffini end organs, Golgi-mazzoni corpuscles,
Vater-pacini corpuscles, Golgi-type endings
and free-nerve endings, (Pedretti 2001).

23. Ruffini-end organs
• Both joint and cutaneous receptors.
• Located in walls of joint capsules.
• Respond at beginning of joint movement
• Decline at mid range
• Increase at extreme joint range.

24. Golgi-mazzoni corpuscles
• Located in joint capsules and tendon surfaces.
• Plenty in connective tissues of hands.
• Detect rapid joint movement
• Discharge greatly under deep pressure or
vibratory stimuli.

25. Vater-pacini corpuscles
• Located in joint capsules and ligaments
• Discharge when joint reaches its maximum
range of motion
• Send warning to cortex when joint reaches end
position range, (Petty, Moore & Gwendolen
2009).

26. Golgi-type endings
• Located in ligaments.
• Monitor rate of joint movement.

27. Free nerve endings
• Support receptors by providing crude
awareness of joint movement
• Mediate touch, pain and temperature in joint
region.

28. Summary
• Therapist should incorporate activities that
stress both voluntary effort and
• Active joint range of motion
• Active movements generate much neurologic
activity

29. Cont.
• Requires collaboration effort of receptors of
skin, muscles and joints.
• A multitude of sensory stimuli to assemblies of
neurons at cortical level, (Lowenstein 1991).

30. Self assessment
1. People who are visually challenged use
Braille as sensory substitution skill. What
type of receptors are responsible for Braille?
And where are they found?
2. What type of sensory receptors is located on
the volar surface of fingers, lips and external
genitalia? What is their function?

31. Cont.
3. The muscle spindle is affected by many
factors, the occupational therapist should
eliminate them before applying facilitative or
inhibition techniques. Explain these factors.
4. Describe the reciprocal innervation principle.

32. Cont.
5. Where are the following sensory receptors
located; baroreceptors, pacinian corpuscles,
GTO, Ruffini end organs, Golgi-mazzoni
corpscles and Vater-pacini corpuscles. What is
their function?

33. Written assignment
• Critically analyze the following sensorimotor
neuromuscular facilitation and inhibition
treatment techniques.
• Reflect on how the technique is performed,
which sensory receptors it affects and whether
it is facilitative or inhibition technique.

34. Cont.
• Light moving touch, fast brushing, icing,
heavy joint compression, tapping, inversion,
vibration, vestibular stimulation,
osteopressure, neutral warmth, slow stroking,
slow rolling, tendinous pressure and
maintained stretch.
• Include precautions of technique if any.

35. Further Reading
• Pedretti, L W (2001), Occupational Therapy
Practice Skills for Physical Dysfunction, St.
Louis, Missouri, Mosby, pp363-391.