Download - VOLUNTARY AND INVOLUNTARY ACTION
![Page 1: VOLUNTARY AND INVOLUNTARY ACTION](https://reader033.vdocuments.us/reader033/viewer/2022061115/546485ccb4af9fd5478b4bad/html5/thumbnails/1.jpg)
Voluntary and Involuntary Actions
![Page 2: VOLUNTARY AND INVOLUNTARY ACTION](https://reader033.vdocuments.us/reader033/viewer/2022061115/546485ccb4af9fd5478b4bad/html5/thumbnails/2.jpg)
• Two types of action controlled by the human nervous system are:
(a)voluntary action
(b)involuntary action
• The peripheral nerves transmit both voluntary and involuntary actions.
![Page 3: VOLUNTARY AND INVOLUNTARY ACTION](https://reader033.vdocuments.us/reader033/viewer/2022061115/546485ccb4af9fd5478b4bad/html5/thumbnails/3.jpg)
Voluntary action
![Page 4: VOLUNTARY AND INVOLUNTARY ACTION](https://reader033.vdocuments.us/reader033/viewer/2022061115/546485ccb4af9fd5478b4bad/html5/thumbnails/4.jpg)
Nature of the control of action
• Involves thought
and free will
• Allows us to consciously
control our skeletal
muscles
![Page 5: VOLUNTARY AND INVOLUNTARY ACTION](https://reader033.vdocuments.us/reader033/viewer/2022061115/546485ccb4af9fd5478b4bad/html5/thumbnails/5.jpg)
Voluntary action is controlled by:
• Cerebrum (fore-brain) which:
(a)coordinates incoming information and then initiates impulses which are sent to the effectors.
(b)may spontaneously initiates actions without any sensory stimulation.
![Page 6: VOLUNTARY AND INVOLUNTARY ACTION](https://reader033.vdocuments.us/reader033/viewer/2022061115/546485ccb4af9fd5478b4bad/html5/thumbnails/6.jpg)
Receptors involved:
• An action may be initiates by the stimulation of a receptor,or by the conscious will of the brain itself
Inborned or learned actions• Voluntary actions are learned
![Page 7: VOLUNTARY AND INVOLUNTARY ACTION](https://reader033.vdocuments.us/reader033/viewer/2022061115/546485ccb4af9fd5478b4bad/html5/thumbnails/7.jpg)
Role of voluntary action:
• To respond with the benefit of experience
Parts of the nervous system involved:
• Reflex arc structures • Interneurons(ascending and descending
fibres )in the spinal cord • Always involved the cerebrum
![Page 8: VOLUNTARY AND INVOLUNTARY ACTION](https://reader033.vdocuments.us/reader033/viewer/2022061115/546485ccb4af9fd5478b4bad/html5/thumbnails/8.jpg)
Speed of action:
• Slow response,as the
cerebrum needs time
to “think”before an
action is carried out.
• Eg. ) if we want to ask
question, we raise our
hands.
![Page 9: VOLUNTARY AND INVOLUNTARY ACTION](https://reader033.vdocuments.us/reader033/viewer/2022061115/546485ccb4af9fd5478b4bad/html5/thumbnails/9.jpg)
Response to the same stimulus:
• The same stimulus may produce various responses.
• Eg.) when you are hungry,you may decide to eat or not to eat, or just need to drink water.
![Page 10: VOLUNTARY AND INVOLUNTARY ACTION](https://reader033.vdocuments.us/reader033/viewer/2022061115/546485ccb4af9fd5478b4bad/html5/thumbnails/10.jpg)
Involuntary action
![Page 11: VOLUNTARY AND INVOLUNTARY ACTION](https://reader033.vdocuments.us/reader033/viewer/2022061115/546485ccb4af9fd5478b4bad/html5/thumbnails/11.jpg)
Nature of the control of action
• Does not involve thought
• Not under the control of the will
• Cannot control the activities
• examples; pumping of the heart and peristalsis
![Page 12: VOLUNTARY AND INVOLUNTARY ACTION](https://reader033.vdocuments.us/reader033/viewer/2022061115/546485ccb4af9fd5478b4bad/html5/thumbnails/12.jpg)
Controlled by:
• Spinal cord(spinal reflex action)
• Hind-brain(cranial reflex action) example blinking of the eyes
![Page 13: VOLUNTARY AND INVOLUNTARY ACTION](https://reader033.vdocuments.us/reader033/viewer/2022061115/546485ccb4af9fd5478b4bad/html5/thumbnails/13.jpg)
Parts of the nervous system involved:
• Reflex arc:afferent neurones(from receptors)to intermediate neurones in spinal cord and out through efferent neurones (to effectors)
• Hind-brain(in cranial reflex action)
![Page 14: VOLUNTARY AND INVOLUNTARY ACTION](https://reader033.vdocuments.us/reader033/viewer/2022061115/546485ccb4af9fd5478b4bad/html5/thumbnails/14.jpg)
Receptors involved:
• A receptor is always involved
![Page 15: VOLUNTARY AND INVOLUNTARY ACTION](https://reader033.vdocuments.us/reader033/viewer/2022061115/546485ccb4af9fd5478b4bad/html5/thumbnails/15.jpg)
Inborned or learned actions
• Reflex actions are inborn (already “hard-wired”at birth
![Page 16: VOLUNTARY AND INVOLUNTARY ACTION](https://reader033.vdocuments.us/reader033/viewer/2022061115/546485ccb4af9fd5478b4bad/html5/thumbnails/16.jpg)
Role of involuntary action:
• To respond quickly to avoid danger
![Page 17: VOLUNTARY AND INVOLUNTARY ACTION](https://reader033.vdocuments.us/reader033/viewer/2022061115/546485ccb4af9fd5478b4bad/html5/thumbnails/17.jpg)
Speed of action:
• Rapid response,as the cerebrum is not involved
![Page 18: VOLUNTARY AND INVOLUNTARY ACTION](https://reader033.vdocuments.us/reader033/viewer/2022061115/546485ccb4af9fd5478b4bad/html5/thumbnails/18.jpg)
Response to the same stimulus:
• The same stimulus always results in the same response(stereotyped response),example as in the knee jerk
![Page 19: VOLUNTARY AND INVOLUNTARY ACTION](https://reader033.vdocuments.us/reader033/viewer/2022061115/546485ccb4af9fd5478b4bad/html5/thumbnails/19.jpg)
Examples of involuntary action:
• Involuntary action(reflex action)involving skeletal muscle:
(a)knee jerk
• Involuntary action involving:
(a)smooth muscles
(b)cardiac muscles
(c)glands,example,normal blood pressure
![Page 20: VOLUNTARY AND INVOLUNTARY ACTION](https://reader033.vdocuments.us/reader033/viewer/2022061115/546485ccb4af9fd5478b4bad/html5/thumbnails/20.jpg)
![Page 21: VOLUNTARY AND INVOLUNTARY ACTION](https://reader033.vdocuments.us/reader033/viewer/2022061115/546485ccb4af9fd5478b4bad/html5/thumbnails/21.jpg)
![Page 22: VOLUNTARY AND INVOLUNTARY ACTION](https://reader033.vdocuments.us/reader033/viewer/2022061115/546485ccb4af9fd5478b4bad/html5/thumbnails/22.jpg)
![Page 23: VOLUNTARY AND INVOLUNTARY ACTION](https://reader033.vdocuments.us/reader033/viewer/2022061115/546485ccb4af9fd5478b4bad/html5/thumbnails/23.jpg)