lesson 3.pdf

Lesson 3. Studying the Brain, and Older Brain Structures Prepared by: Livien U. Ciabal, PhD, RGC, RPm  2.Describe the components of the brainstem, and summarize the functions of the brainstem, thalamu Studying the Brain, and Older Brain Structures A. Older Brain Structures B....

Lesson 3. Studying the Brain, and Older Brain Structures Prepared by: Livien U. Ciabal, PhD, RGC, RPm  2.Describe the components of the brainstem, and summarize the functions of the brainstem, thalamu Studying the Brain, and Older Brain Structures A. Older Brain Structures B. The Tools of Discovery: Having our Heads Examined Intended Learning Objectives 1. Describe several techniques for studying the brain’s connections to behavior and mind. 2. Describe the components of the brainstem, and summarize the functions of the brainstem, thalamus, and cerebellum. 3. Describe the limbic system’s structures and functions. “If the human brain were so simple that we could understand it, we would be so simple that we couldn’t” -Emerson Pugh, The Biological Origin of Human Values (1977) Older Brain Structures The Brainstem ▪ The oldest part and central core of the brain, beginning where the spinal cord swells as it enters the skull The Brainstem ▪ In vertebrate anatomy, the brainstem is the most inferior portion of the brain, adjoining and structurally continuous with the brain and spinal cord. ▪ The brainstem gives rise to cranial nerves 3 through 12 and provides the main motor and sensory innervation to the face and neck via the cranial nerves. * Brainstem Function regulation of heart rate, breathing, sleeping, and eating. It also plays a role in conduction. The Brainstem ▪ regulation of cardiac and respiratory function. ▪ It regulates the central nervous system (CNS) and is essential in maintaining consciousness and regulating the sleep cycle. The Brainstem Components of the Brainstem The three components of the brainstem are : ▪ medulla oblongata, ▪ midbrain ▪ and pons https://courses.lumenlearning.com/boundless-ap/chapter/the-brain- stem/  Components of the Brainstem The medulla oblongata (myelencephalon) is the lower half of the brainstem continuous with the spinal cord. Its upper part is continuous with the pons. Components of the Brainstem The medulla is often divided into two parts: 1. An open or superior part where the dorsal surface of the medulla is formed by the fourth ventricle. 2. A closed or inferior part where the metacoel (caudal part of fourth ventricle) lies within the medulla oblongata. Components of the Brainstem The midbrain (mesencephalon) is associated with vision, hearing, motor control, sleep and wake cycles, alertness, and temperature regulation. Components of the Brainstem The pons (part of metencephalon) lies between the medulla oblongata and the midbrain. Components of the Brainstem The Pons contains nuclei that relay signals from the forebrain to the cerebellum,* The Thalamus ▪ The thalamus receives information from all the senses except smell and routes it to the higher brain regions that deal with seeing, hearing, tasting, and touching. The Thalamus ▪ The thalamus is part of the limbic system. ▪ The limbic system is the part of the brain involved in our behavioral and emotional responses, especially when it comes to behaviors we need for survival: feeding, reproduction and caring for our young, and fight or flight responses. The Thalamus The Reticular Formation ▪ Inside the brainstem, between your ears, lies the reticular formation, a neuron network that extends from the spinal cord right up through the thalamus ▪ The reticular formation consists of more than 100 small neural networks with varied functions including motor control, cardiovascular control, pain modulation, sleep, and habituation.  Reticular Formation Widespread connections Arousal of the brain as a whole Reticular activating system (RAS) Maintains consciousness and alertness Functions in sleep and arousal from sleep The Reticular Formation Functions: 1.Somatic motor control: 2.Cardiovascular control: 3.Pain modulation: 4.Sleep and consciousness: 5.Habituation: The Reticular Formation  The Cerebellum –helps coordinate voluntary movement and balance The Cerebellum ▪ Extending from the rear of the brainstem is the baseball- sized cerebellum, meaning “little brain,” which is what its two wrinkled halves resemble Figure 6 The Cerebellum ▪ The cerebellum, which looks like a separate structure attached to the bottom of the brain, plays an important role in motor control. ▪ The cerebellum can be separated into three lobes: ▪ flocculonodular lobe, Figure 6 ▪ anterior lobe, and ▪ posterior lobe  The Cerebellum ▪ The cerebellum enables nonverbal learning and memory. ▪ It also helps us judge time, modulate our emotions, and discriminate sounds and textures (Bower & Parsons, 2003).  Parts of the Brain THALAMUS amygdala hippocampus → Relays messages pituitary CEREBELLUM → Coordination and balance BRAINSTEM → Heart rate and breathing The Limbic System Figure 7  The Limbic System limbic system neural system (including the hippocampus, amygdala, and hypothalamus) located below the cerebral hemispheres; associated with emotions and drives.  The Limbic System ▪ Hypothalamus ▪ neural structure lying below (hypo) the thalamus; directs several maintenance activities ▪ eating ▪ drinking ▪ body temperature ▪ helps govern the endocrine system via the pituitary gland ▪ linked to emotion ▪ (show video)  The Limbic System Hypothalamus, pituitary, amygdala, and hippocampus all deal with basic drives, emotions, and memory Hippocampus → Memory processing Amygdala → Aggression (fight) and fear (flight) Hypothalamus → Hunger, thirst, body temperature, pleasure; regulates pituitary gland (hormones)  The Limbic System Amygdala –two almond- shaped neural clusters that are components of the limbic system and are linked to emotion and fear  The Limbic System The amygdala and the frontal lobes work together to regulate emotional responses. The amygdala supplies the emotional feelings while the frontal lobe makes the judgment regarding the appropriate expression of the emotion. Have students imagine what types of behaviors would occur if each of these components had to work alone instead of together. Figure 11 The Tools of Discovery: Having our Heads Examined Figure 1. An electroencephalogram providing amplified tracings of waves of electrical activity in the brain Here it is displaying the brain activity of a woman who has epilepsy. Electroencephalogram (EEG) an amplified recording of the waves of electrical activity sweeping across the brain’s surface. These waves are measured by electrodes placed on the scalp. An electroencephalogram (EEG) is an amplified readout of such waves. Researchers record the brain waves through a shower-cap-like hat that is filled with electrodes covered with a conductive gel. CT (computed tomography) Scan a series of X-ray photographs taken from different angles and combined by computer into a composite representation of a slice of the brain’s structure. (Also called CAT scan.) PET (Positron Emission Tomography) Scan a visual display of brain activity that detects where a radioactive form of glucose goes while the brain performs a given task. PET (Positron Emission Tomography) Scan Figure 2 MRI (Magnetic Resonance Imaging) a technique that uses magnetic fields and radio waves to produce computer - generated images of soft tissue. MRI scans show brain anatomy.  MRI (Magnetic Resonance Imaging) Figure 3 MRI scan of a healthy individual (left) and a person with schizophrenia (right) Note the enlarged ventricle, the fluid- filled brain region at the tip of the arrow in the image on the right. fMRI (functional MRI) a technique for revealing blood flow and, therefore, brain activity by comparing Figure 5 successive MRI scans. fMRI scans show brain function as well as its structure.  The Brain – History Channel http://www.youtube.com/watch?v=iE3M gMFfI6U Brain Activities Prepared by: Livien U. Ciabal, RGC, RPm Activity #1 Answer Activity #2 Answer Answer Activity #3 Activity #2  Learning Engagement #3 Come up with DIGITAL VIDEO CLIP of ` CREATIVE STORIES in which the PARTS OF THE BRAIN ARE CHARACTERS IN A FAIRY TALE OR SUPERHERO STORY. The brain-part characters should behave in ways consistent with their actual function in the brain. Thank you !