Structure of the brain By Sanjay Sabu The Nervous system • The nervous system is compromised of two main parts: • The central nervous system is made up of the brain and spinal cord. • The peripheral nervous system is made up of nerves that branch off from the spinal cord and extend to all parts of the body to allow them to move. The function of the Brain The brain controls our thoughts, memory and speech, movement of the arms and legs, and the function of many organs within our body. The brain also controls autonomous functions such as breathing and swallowing. Reflexes • Reflexes protect the body. Inhibitory interneurons aid in the proper functioning of reflexes. The reflex arc is made up of five steps: sensor, sensory neuron, control core, motor neuron, and muscle. Cerebral cortex • The cerebral cortex is the central nervous system's largest neural integration site. Attention, perception, memory, perception, memory, language, and consciousness all depend on it. Cerebellum • The cerebellum, which stands for "little brain," is a central nervous system. Cerebellar dysfunction often manifests as motor signs, indicating that it plays an important role in motor control. It is particularly involved in movement coordination, precision, and timing, as well as motor learning. Medulla • The medulla oblongata is a structure at the base of your brain that links the brain to the spinal cord through the brain stem. It's responsible for transmitting signals from your spinal cord to your brain. It's also important for maintaining the health of your cardiovascular and respiratory systems. Hypothalamus • The hypothalamus is involved in a variety of everyday activities such as eating and drinking, maintaining body temperature and energy, as well as the process of memorising and stress management. Along with its interactions with the pituitary gland, it also influences the endocrine system. Pituitary Gland • The pituitary gland regulates metabolism, development, sexual maturation, reproduction, blood pressure, and many other essential physical functions and processes through the secretion of hormones. What are the difficulties associated with investigating and treating brain disease and brain damage? • Because of the structure and delicacy of the brain, diagnosing and treating brain disorders can be challenging. If surgery is performed, it is possible that further damage or side effects may be produced, lowering the patient's quality of life. • Because of a natural barrier in the brain, many neurological conditions are difficult to treat. The blood-brain barrier is a specialised system of cells that serves as a gatekeeper for the brain, trapping harmful substances while allowing essential nutrients to pass through. The case of Phineas Gage • Phineas Gage is often referred to as one of the most famous patients in neuroscience. He experienced a traumatic brain injury when an iron rod was driven through his entire skull, destroying much of his frontal lobe. Gage miraculously survived the accident. • Gage taught us that complex functions such as decision-making and social cognition are largely dependent upon the frontal lobes. MRI Scans for the Brain • MRI can detect a variety of conditions of the brain such as cysts, tumors, bleeding, swelling, developmental and structural abnormalities, infections, inflammatory conditions, or problems with the blood vessels. It can determine if a shunt is working and detect damage to the brain caused by an injury or a stroke. Advantages of MRI • MRI is non-invasive and does not use radiation • MRI does not involve radiation • MRI contrasting agent is less likely to produce an allergic reaction that may occur when iodine-based substances are used for x-rays and CT scans • MRI gives extremely clear, detailed images of soft-tissue structures that other imaging techniques cannot achieve • MRI can easily create hundreds of images from almost any direction and in any orientation • Unlike techniques that examine small parts of the body (i.e. ultrasound or mammography) MRI exams can cover large portions of the body • MRI can determine if a cancer has spread, and help determine the best treatment Disadvantages of MRI • MRI is expensive ($1000-$1500) • MRI will not be able to find all cancers (i.e. breast cancers indicated by microcalcifications) • MRI is not painful, but the patient must remain still in an enclosed machine, which may be a problem for claustrophobic patients • An undetected metal implant in a patient’s body may be affected by the strong magnet of the MRI unit • There is a small chance that a patient could develop an allergic reaction to the contrasting agent, or that a skin infection could develop at the site of injection • If a patient chooses to be sedated for the scanning, there is a slight risk associated with using the sedation medication Electrically stimulating the brain • Electrical brain stimulation (EBS), also referred to as focal brain stimulation (FBS), is a form of electrotherapy and technique used in research and clinical neurobiology to stimulate a neuron or neural network in the brain through the direct or indirect excitation of its cell membrane by using an electric current. • Electrical stimulation of the brain is a relatively new technique used to treat chronic pain and tremors associated with Parkinson disease Advantages of Electrically stimulating the Brain • Symptom Reduction: DBS often reduces symptoms significantly. These include motor symptoms like stiffness, tremor, slowness and dyskinesia. DBS has also been shown to aid in on/off fluctuations, improve mood and quality of life, and increase overall energy level. • Little to No Damage: In contrast to previous methods, DBS does not damage portions of the brain, nor remove nerve cells. • Decreased Medication Needs: Utilizing DBS in addition to levodopa could decrease a person’s need for medication, thus, decreasing medication access and cost issues, as well as levodopa side effects. • Individualized Treatment: Electrodes and stimulation frequency and intensity can be controlled by physicians and the individual with DBS, and can be subjectively altered when needed. Disadvantages of Electrically Stimulating the Brain • Invasive and Awake during Procedure: The procedure does involve an incision to the scalp, and access to deep parts of the brain. Additionally, most individuals are awake during the procedure, which could be a scary situation for some. • Not All Symptoms Addressed: Typically, symptoms that would respond to levodopa respond the best to DBS. Other symptoms that aren’t managed by levodopa are generally unaffected. • Surgical Side Effects: As with most surgical procedures, there are risks associated with surgery itself. These include the risk of bleeding, stroke, infection, and accumulating fluid in the brain. Also, since the brain is a complex and sensitive organ, it is possible for essential areas of the brain to get hurt during the procedure and cause additional symptoms unrelated to PD. • Future Danger around Certain Electronics: Basic electronics are usually fine for those with DBS to be around, however, larger, more powerful machines, like total body coil MRI, may be off-limits post-procedure. • Malfunction and Battery Replacement: It is possible for the hardware to malfunction, wires to disconnect, and the electrodes to shift. Additionally, the battery life of the devices and controllers need to be monitored relatively frequently. • Expensive: Although many insurance companies may cover part or all of DBS, the procedure can run anywhere from $30,000-$100,000. • Results Aren’t Immediate: It can take months to determine the exact balance of DBS stimulation and medications to optimally control symptoms. While certain symptoms may subside almost immediately, it may take a long amount of time to find the right combination for long-term effects. Beneficial Interventions for Brain Cancer and side effects • Treatment options include those described below, such as surgery, radiation therapy, chemotherapy, and targeted therapy. For a low-grade brain tumour, surgery may be the only treatment needed especially if all of the tumour can be removed. • For radiation therapy the side effects are headaches, hair loss, vomiting and trouble with memory/ speech. • For chemotherapy the side effects are hair loss, fatigue and bruising and bleeding. • For targeted therapy the side effects are skin problems and liver problems. 3 AMAZING FACTS ABOUT THE BRAIN THE HUMAN BRAIN CONTAINS APPROXIMATELY ONE HUNDRED BILLION NEURONS THE HUMAN BRAIN WILL TRIPLE ITS SIZE THE FIRST YEAR OF LIFE MULTITASKING IS IMPOSSIBLE
