This document summarizes several postural and autonomic reflexes. It describes the afferent pathway that carries sensory information, integrating centers in the brainstem and spinal cord, and efferent pathways consisting of motor neurons. Specific reflexes discussed include the crossed extensor reflex which extends the opposite limb in response to a stimulus, positive and negative supporting reactions in the limbs, and tonic neck and cord righting reflexes which help correct body position when off balance. Autonomic reflexes mentioned are cardiovascular, gastrointestinal, and bladder emptying.

1. Autonomic & Postural Reflex
Dr.Sara Sadiq
(MBBS, M.Phil)

3. • Afferent Pathway  comes from the eyes,
the vestibular apparatus and the
proprioceptors
• Integrating Centers  are formed by
neuronal network in the brain stem and
spinal cord
• Efferent Pathway  α-motor neurons
supplying the various skeletal muscles i.e.
the effector organ
Reflex Arc Of Postural Reflex

6. • Flexion of a limb  Extension of the
opposite limb  entire body pushed away
from the stimuli causing pain.
• Stimuli  noxious stimuli
• Center  spinal cord
2. Crossed extensor reflex

8. • Used to support the body.
• Magnet reaction  locus of pressure
determines the direction of extension
• Stimuli  Press the pads of (fingers, toes)
and dorsiflex the (hand, foot)
• Afferent = from the skin & muscle
• Effect = Hand, foot extended to support
the body.
• Limbs become as solid rigid pillars.
3. Positive supporting reaction

9. • Opposite to the positive supporting
reaction.
• Stimulus  stretch
• Receptor  Proprioceptor
• Center  spinal cord
• Response  Release of positive
supporting reaction.
• The limb no longer supports the body
weight.
4. Negative supporting reaction

10. • Stimulus  Head turned to side
• Receptors  Neck proprioceptors
• Response  Fore legs extend
 Hind legs flexed
• Center  Medulla
Tonic Neck Reflex

11. • Righting reflexes help to correct the position
of the body when it goes off balance and
falls down
• When lies on the ground, the side in contact
with the ground is constantly stimulated
while the other side is not
• This differential stimulation of the deep
structures in the body wall reflex rights the
head
• Center  red nucleus lying in the mid brain
Cord Righting Reflex

13. • Cardiovascular autonomic reflex
• Gastrointestinal autonomic reflex
• Emptying of the bladder
Autonomic Reflexes