The Brain

1. The Brain

3. The Brain The central nervous system begins as the neural tube which has a fluid-filled cavity called the neurocoel. The cephalic portion of the tube enlarges creating 3 large divisions called the primary brain vesicles:

4. the prosencephalon or the forebrain, the mesencephalon or the midbrain, and the rhombencephalon or the hindbrain.

6. The neurocoel will contain to develop within the major portions of the brain and form ventricles lined by ependymal cells. Develop continues until the brain is formed.

7. Development The prosencephalon is also known as the forebrain. The anterior portion develops into the cerebrum and basal ganglia, and the posterior portion develops into the diencephalon .

8. Development The mesencephalon is also known as the midbrain.

9. Development The rhombencephalon is also known as the hindbrain. This gives rise to the cerebellum, the pons, and the medulla oblongata.

10. Four Major Sections • Cerebrum • Diencephalon • Cerebellum • Brain Stem

11. Cerebrum

12. Corpus Callosum

13. Gyri, Sulci, Fissures

14. Lobes of the Cerebrum Frontal Parietal Temporal Occipital

15. Broca’s Area

16. Dopamine The majority of cerebral tissue is white matter; however, there are some areas of gray matter called basal ganglia which are largely regulated by the neurotransmitter dopamine.

18. Dopamine & Parkinson’s Dopamine regulates body movements and facial expressions. A lack of dopamine within the basal ganglia can result in Parkinson’s disease. Treatments include L-Dopa, electrical stimulations, or fetal tissue transplants.

22. The Diencephaon The diencephalon is located between the cerebral hemispheres. Its main function is to process sensory information. The diencephalon contains the thalamus, the posterior pituitary gland, the pineal gland, and the hypothalamus.

23. The thalamus functions as a relay station for sensory information. The pituitary and pineal glands are a part of the endocrine system. The hypothalamus has a variety of functions - emotions, hormone production, and autonomic responses (bp or heart rate).

26. The Cerebellum The cerebellum is located beneath the occipital lobe and is divided into two lateral hemispheres. Similar to the cerebrum, the outer layer is a thin layer of gray matter called the cerebellular cortex.

27. This portion of the brain is involved in communication controlling movements, balance, and posture.

29. The Brain Stem The brain stem is located at the base of the base and contains the nerve fibers that connect to the spinal cord. There are 3 major structures in the brain stem: the midbrain, the pons, and the medulla oblongata.

31. The Brain Stem The midbrain relays impulses from the lower parts of the brain stem and spinal cord to other parts of the brain. The pons also relay impulses but the relay is between the cerebrum and the medulla oblongata.

32. The Brain Stem The medulla oblongata is the elongated area under the occipital lobe. It has some involvement in communication, and it controls several visceral areas – cardiac, blood pressure, and respiration.

34. The Limbic System

35. The Reticular Formation

36. Sleep Stages

37. Protection The three layers of meninges are continuous with the spinal meninges. The three layers are the duramater,thearachnoid mater, and the pia mater. The dura mater’s outside layer is attached to the periosteum of the skull.

38. Protection The arachnoid mater covers the brain and provides a smooth surface unlike that of the brain. The pia mater sticks to the surface of the brain and is anchored by astrocytes. It extends into the fissures and accompanies the blood vessels as they penetrate the surface of the brain.

41. Cerebrospinal Fluid

42. Brain’s Blood Supply

43. The circle of Willis encircles the stalk of the pituitary gland and provides important communications between the blood supply of the forebrain and hindbrain

44. Brain’s Blood Supply