Structure and Functions of cerebrum

Cerebrum, structure and Functions.

1. PRACTICE TEACHING Name: Maneera Gulzar Class: M.SC. Nursing 1 st year Specialty: Medical Surgical Nursing Topic: Structure and Functions of Cerebrum

2. INTRODUCTION The Nervous system is the major controlling, regulatory, and communicating system in the body. It is the center of all mental activity including thought, learning, and memory. Together with the endocrine system, the nervous system is responsible for regulating and maintaining homeostasis. The parts of Nervous system are as: Central Nervous system Peripheral Nervous system

3. Central nervous system consists of : Brain and Spinal Cord. Peripheral Nervous system consists of: all the nerves outside Brain and Spinal cord.

4. Overview OF BRAIN Brain is the most complex part of the human body. It weighs about 1300-1400 grams in adults and 350-400 grams in newborn babies.

5. PARTS OF THE BRAIN

6. FLOWCHART OF HUMAN BRAIN

7. PARTS OF BRAIN

8. PARTS OF BRAIN(Sagittal view)

9. Parts of brain (Cross sectional View)

10. Cerebrum It is the largest and most anterior part of the Brain and accompanies about 2/3 rd of total weight of Brain. Location: It is located in front area of skull and top of the Brainstem and lie in anterior and middle cranial fossa. Functions: Performs higher functions: Interpreting touch, vision and hearing, speech, reasoning, emotions, learning and fine control of movements.

11. Cranial Fossa

12. CEREBRUM Cerebrum is divided into two “C” shaped Hemispheres by longitudinal fissure. Fig: Superior view of Brain

13. cerebrum Deep within the brain the hemispheres are connected by a mass of white matter called the Corpus Callosum. Corpus Callosum allow communication between two hemispheres. The Falx Cerebri is formed by the Dura matter. It separates the two hemispheres and penetrates to the depth of the corpus Callosum.

14. Cerebral Hemispheres

15. Gyri and sulci The cerebral cortex shows many infoldings or furrows of varying depth. The exposed areas of the folds are the Gyri (elevated part). Gyri are separated from one another by Sulci (fissures). Function: These increase surface area of the brain. Fissure: Deep sulci form fissure.

16. Sulci and Gyri

17. CONTD…. Fissure divides cerebral cortex into 4 lobes: Fontal lobe Parietal lobe Temporal lobe Occipital lobe The lobes take the name of the bone of the cranium under which they lie.

18. LOBES OF CEREBRUM

19. Main cerebral fissures Longitudinal fissure: divides Cerebrum into 2 hemispheres i.e., Right and Left hemisphere. Central fissure: between Frontal and Parietal lobe. Lateral fissure: also known as Sylvain fissure, lies between frontal and temporal lobe. Parieto-occipital fissure: between parietal and Occipital lobe. Transverse fissure: between Cerebrum and Cerebellum

20. Cerebral Fissures: Anterior and Posterior view

21. Cerebral Fissures

22. Functions of cerebrum (General) Functions: Performs higher functions: Mental activities: Memory, intelligence, sense of responsibility, thinking, reasoning, moral sense and learning. Sensory perception includes: perception of pain temperature, touch, sight, hearing, taste and smell. Initiation and control of skeletal muscle contraction and therefore voluntary movement.

23. Lobes of cerebrum and functional areas Each cerebral hemisphere is subdivided into 4 lobes. Lobes have different areas which perform different functions. These are known as Functional areas of Cerebral Cortex.

24. Frontal lobe Frontal lobe: Located at the front of each cerebral hemisphere. Present in front of Parietal lobe and above the Temporal lobe. Areas: Primary motor area: located immediately anterior to Central sulcus. Functions: controls voluntary movements of skeletal muscles. Motor area of right hemisphere controls movement of left side of body and vice versa.

25. primary motor area

26. 2. The Premotor area: this lies in the frontal lobe immediately anterior to the primary motor area. Function: the neurons here coordinate movement initiated by the Primary motor cortex, ensuring that learned pattern of movements can be repeated. 3. Broca’s area(motor speech area): this is situated in the frontal lobe just above the lateral sulcus. Function: it controls muscle movement needed for speech. It is dominant in the left hemisphere in right-handed people and vice versa.

27. 4. The Prefrontal area: this extends anteriorly from the Premotor area to include the remainder of the frontal lobe. It is a large area and is more highly developed. Function: it performs intellectual functions like thinking, planning, organizing, problem solving, emotions, behavioral control, decision making and personality.

28. Parietal lobe Parietal lobe: located immediately behind the frontal lobe. Areas: The Somatosensory area: located immediately behind the Central sulcus. Functions: sensation of pain, temperature, pressure, touch, awareness of muscular movement and the position of joints(proprioception) are perceived. *The Somatosensory area of the right hemisphere receives impulses from the left side of the body and vice versa.

29. The taste area: this lies just above the lateral sulcus in the deep layers of the Somatosensory area. Function : here impulses from sensory receptors in taste buds are received and perceived as taste.

30. Temporal Lobe Temporal lobe: located on sides of head. Areas: Wernicke’s area(sensory speech area): situated in temporal lobe adjacent to the parieto-occipitotemporal area. Functions: Perceiving spoken word, comprehension and intelligence. The Auditory area: lies immediately below the lateral sulcus within the temporal lobe. Function: the nerve cells receive and interpret impulses transmitted from the inner ear by the cochlear part of the vestibulocochlear nerve.

31. The Olfactory area: lies deep within the temporal lobe where impulses from the nose , transmitted via the olfactory nerves are received and interpreted.

32. Occipital lobe Occipital lobe: located at the back of the Brain. Areas: 1 . Visual area: lies behind the Parieto-occipital sulcus and includes the greater part of the occipital lobe. Function: the optic nerve pass from the eye to this area, which receives and interprets the impulses as visual impressions. Parieto-occipitotemporal area: lies behind the Somatosensory area and includes most of the parietal lobe. Function: Spatial awareness, interpreting written language and the ability to name objects. *Objects can be recognized by touch alone because of the knowledge from past experience retained in this area .

33. summary The Nervous system is the major controlling, regulatory, and communicating system in the body. T he parts of Nervous system are as: Central Nervous system and Peripheral Nervous system. Brain consists of 3 main pasts: Forebrain, Midbrain and Hindbrain. It is the largest and most anterior part of the Brain and accompanies about 2/3 rd of total weight of Brain Cerebrum performs higher functions: Interpreting touch, vision and hearing, speech, reasoning, emotions, learning and fine control of movements. Cerebrum is divided into 4 lobes: Frontal lobe, Parietal lobe, Temporal lobe and Occipital Lobe.

34. Bibliography Anne. W, Allison. G. Anatomy and Physiology in Health and Illness. 12 th edition, Elsevier Publications; p 151-158. Tortora. G, Derrickson.B. Principles of Anatomy and Physiology.14 th edition, Wiley Publishers; p 488-500. Bethesda. Brain Basics(2019). Retrieved on 11 th December 2021. www.ninds.nih.gov/Disorders . Hans. S. Everything about Cerebrum(2020). Retrieved on 15 th December 2021. www.medicalnewstoday.com . Boundless Anatomy and Physiology. The Cerebrum(2020). Retrieved on 15 th December 2021. www.courses.lumenlearning.com/boundless

35. evaluation Q1.Enlist parts of Brain? Q2. Enlist lobes of Cerebrum? Q3. which fissure divides Cerebrum into two hemispheres? Q4. What is the function of Broca’s area?