Functional anatomy and Physiological significance of Somatomotor & Somatosensory System.

1. PHYSIOLOGY OF SOMATOSENSORY
& SOMATOMOTOR SYSTEM
Dr. Aniket A Shilwant
Assistant Professor
Dept. of Sharir Kriya
GJPIASR, CVM University

2. Table of Contents
 Introduction
 Somatosensory system
 Somatosensory pathway
 Trigeminal Somatosensory pathway
 Somatomotor system
 Somatomotor functions
 Somatomotor pathway

4. SOMATOSENSORY SYSTEM
Sensory pathways
1) Somatosensory pathways - Conveys impulses from
receptors in skin, muscles, joints and tendons, etc.
2)Viscero-sensory pathways - Conveys impulses from
receptors in visceral or soft organs of the body.

5. SOMATOSENSORY PATHWAY
 Ist Order Neuron – PNS to CNS (Posterior nerve root ganglion in SC)
 IInd Order Neuron – CNS (SC) to CNS (Subcortical areas)
 IIIrd Order Neuron – CNS (Subcortical areas) to Higher CNS (Cerebral Cortex)

6. TRIGEMINAL SOMATOSENSORY PATHWAY
 Face
 Teeth
 Periodontal tissues
 Oral cavity
 Nasal cavity
 Cranial dura mater
 Major part of scalp to sensory cortex
 Proprioceptive impulses from extrinsic muscles of the eyeball.

7. TRIGEMINAL SOMATOSENSORY PATHWAY
Lemniscus
 Spinal Lemniscus
 Lateral Lemniscus
 Medial Lemniscus
 Trigeminal Lemniscus

8. Sensation Receptor Ist ORDER N IInd ORDER N
IIIrd ORDER N
Tactile sensation
Tactile localization
Tactile discrimination
Vibratory sensation
Stereognosis
Merkel’s Disk
Meissner’s Corpuscles
Posterior
Nerve Root
Ganglion
Nucleus Cuneatus
Nucleus Gracilis
Sensory Cortex
Crude touch
Pressure
Pacinian Corpuscle
Thalamus
(Ant. Spino Thalamic)
Temperature
Cold – Krause End Bulb
Warm – Ruffini End Bulb
Thalamus
(Lat. Spino Thalamic)
Pain
Free Nerve endings
(Fast & Slow fibers)
Thalamus
(Lat. Spino Thalamic)
Conscious Kinesthetic
Sensation Proprioceptors
Muscle Spindle
Golgi tendon
apparatus
Thalamus
(F. Cuneatus & Gracilis)
Sub-Conscious
Kinesthetic
Sensation
Cerebellum
(Ant. & Lat. - Spino
Cerebellar)
Cerebellum

9. SOMATOMOTOR SYSTEM
 Concerned with motor activities.
 Motor activities 2types-
a) Skeletal muscles - concerned with body posture and movement.
b) Smooth muscles - concerned with functions of various visceral organs.

10. SOMATOMOTOR SYSTEM FUNCTIONS
 Smooth, precise and accurate voluntary movements
 Learned motor and Skilful activities
 Neuromuscular coordination

11. SOMATOMOTOR PATHWAY
Pyramidal tracts
Anterior Corticospinal tract
Lateral Corticospinal tract
Extrapyramidal tracts
Anterior Vestibulospinal tract
Lateral Vestibulospinal tract
Tectospinal tract
Reticulospinal tract
Rubrospinal tract
Olivospinal tract

12. Thank You All !!!
Dr. Aniket A. Shilwant
Assistant Professor
Sharir Kriya Dept.
GJP-IASR, CVM University
Email –
ayuraniket18@gmail.com
http://ayugjac.edu.in/Staff_CV.aspx?dl=dn3Mja19480dn3Mja19
http://scholar.google.co.in/citations?user=636K2sMAAAAJ&hl=en
https://www.researchgate.net/profile/Aniket_Shilwant