1. NEURAL CONTROL OF BREATHING
PONS
MEDULLA

2. Neural Control Of Breathing
Voluntary
Cerebral cortex
Autonomic
Medullary Centers
Dorsal Respiratory Group
Ventral Respiratory Group
Pontine Centers
Pneumotaxic Center
Apneustic
Center

3. Respiratory Center
The respiratory center is composed of several groups of neurons located bilaterally in the medulla oblongata and pons of the brain stem.
It is divided into :
Dorsal Respiratory Group
Ventral Respiratory Group
Pneumotaxic Center
Apneustic Center

4. Brainstem Respiratory Centres
Pontine center
Pons
Dorsal Respiratory Group
Medulla
Ventral respiratory group
- Nucleus ambiguus
- Nucleus retroambigualis
To larynx and bronchi
To respiratory muscles

5. DORSAL RESPIRATORY GROUP
The dorsal respiratory group of neurons extends along most of the length of the medulla. Most of its neurons are located within the nucleus of the tractus solitarius.
This group of neurons emits repetitive bursts of inspiratory neuronal action potentials.
The basic rhythm of respiration is generated mainly in the dorsal respiratory group of neurons.

6. VENTRAL RESPIRATORY GROUP
The Ventral respiratory group of neurons is found in the nucleus ambiguus rostrally and the nucleus retroambiguus caudally.
The VRG contains both inspiratory and expiratory neurons.
The neurons of the ventral respiratory group remain almost totally inactive during normal quiet respiration.
The VRG is responsible for motor control of inspiratory and expiratory muscles during exercise.
They are especially important in providing the powerful expiratory signals to the abdominal muscles during very heavy expiration

7. Pontine Respiratory Center
Pons contains 2 centres for control of respiration:
Pneumotaxic Center
Apneustic Center

8. INTEGRATION

9. HERRING-BRUER’S REFLEX
Inspiratory Center
Phrenic Nerve
Diaphragm Contracts & Lung Expands
Stretch Receptors on Lungs Activated
Vagus Nerve
Inhibitory Signal

10. Brainstem Respiratory Centres
Pontine center
Pons
Dorsal Respiratory Group
Medulla
Ventral respiratory group
- Nucleus ambiguus
- Nucleus retroambigualis
To larynx and bronchi
To respiratory muscles

11. LESIONS Produces apneustic effect – long, powerful inspirations. Pons
Irregular but Rhythmic Breathing
Medulla
Stops breathing since no automated output to respiratory system – cause of death in hanging.

12. ABNORMAL RESPIRATORY PATTERNS
Apneusis
Biot Breathing
Cheyne Stroke Breathing
Vagal Breathing