Chapter 2.2: Anatomy of the Nervous System - BIOPSYCH - PDF

CHAPTER 2.2 ANATOMY OF THE NERVOUS SYSTEM NERVOUS SYSTEM - Coordinates all activities of the body STANDARD ANOTOMICAL POSITION - Enables the body to responds and ada...

CHAPTER 2.2 ANATOMY OF THE NERVOUS SYSTEM NERVOUS SYSTEM - Coordinates all activities of the body STANDARD ANOTOMICAL POSITION - Enables the body to responds and adapts to changes It refers to the specific body CELLS OF THE NERVOUS SYSTEM orientation used when ANATOMY OF NEURONS describing an individual’s NEURONS anatomy. It consists of the - Are cells that are specialized for the body standing upright and reception, conduction, and transmission of facing forward with the legs electrochemical signals. parallel to one another. The EXTERNAL ANATOMY OF upper limbs, or arms, hang at NEURONS either side and the palms face forward. NUCLEUS PLANES OF THE BODY - contains the cell's genetic material. These are imaginary CELL BODY reference points that - also called the soma, provides energy, divide the body into maintains structure, and contains genetic various sections in information. order to help DENDRITE describe relative - are projections from the cell body. The anatomy. main function of dendrites is to receive information from other neurons. SAGITTAL PLANE AXON - Divides the body into right and left parts. - long, thin nerve fiber that transmits CORONAL PLANE electrical impulses away from a neuron's cell - Divides the body into anterior and posterior body. parts. MYELIN SHEATH TRANSVERSE PLANE - a fatty layer that surrounds and insulates - Divides body into superior and inferior nerve cells. parts. BIOPSYCH -KML CHAPTER 2.2 NODE OF RANVIER UNIPOLAR NEURON - are gaps in the myelin sheath that regenerate action potentials along axons, - A neuron with one process allowing for faster extending from its cell body. and more efficient communication. - Only occurs in invertebrate - action potential is a rapid change in the glands and muscles. voltage across a cell membrane AXON TERMINAL PSEUDO-UNIPOLAR NEURON - the ends of axons which transmit messages to other cells via use of neurotransmitters at - the nerve process extending synapses. from the cell body splits into two branches or axons. - Sensory neuron BIPOLAR NEURON - has two distinct structures extending from the cell body. One is an axon, and the other is a dendrite. - olfactory epithelium, retina, and CLASSES OF NEURONS certain nerves within the ear MULTIPOLAR NEURON - A neuron with more than two process extending from its cell body - are present throughout a person’s CNS, including the brain and associated nerves in the autonomic nervous system. BIOPSYCH -KML CHAPTER 2.2 GLIAL CELLS TWO DIVISIONS OF CNS - Found throughout the nervous system A.CENTRAL NERVOUS SYSTEM (CNS) - The glial cells surround neurons and provide - Division of the support for and insulation between them. nervous system that is - Glial cells are the most abundant cell types located within the in the central nervous system. skull and spine. TYPES OF GLIAL CELLS - Is the integrating Oligodendrocytes - their main functions are and control center of the nervous system. to provide support and insulation to axons in BRAIN the central nervous system. - Part of the CNS that is located in the skull Schwann cells - any of the cells in the - Controls all major body functions. peripheral nervous system that produce the - the organ inside the head that controls myelin sheath around neuronal axons. They thought, memory, feelings, and activity. guide axonal regeneration (regrowth) after FIVE MAJOR DIVISIONS OF THE damage. BRAIN Microglia – They respond to injury or disease by multiplying, engulfing cellular debris, and triggering inflammatory responses. Astrocytes – they cover the outer surfaces of blood vessels that course through the brain. They play a role in allowing the passage of some chemicals from blood into CNS and in blocking other chemicals. HINDBRAIN GENERAL LAYOUT OF THE NERVOUS SYSTEM - a region of the brain that controls many vital functions, including breathing, heartbeat, and motor coordination. BIOPSYCH -KML CHAPTER 2.2 MYELENCEPHALON (MEDULLA) MESENCEPHALON (MIDBRAIN) - The most posterior - Is a portion of the division of the brain it is central nervous system composed largely of associated with vision, tracts carrying signals hearing, motor control, between the rest of the sleep/wake, arousal and brain and the body. temperature regulation. - Medulla Oblongata helps control vital TWO DIVISIONS OF processes like your heartbeat, breathing and MESENCEPHALON blood pressure. TECTUM –dorsal (top) part of the midbrain. METENCEPHALON INFERIOR COLLICULI – is involved in - Part of the auditory processing. hindbrain that SUPERIOR COLLICULI - is involved in differentiates into visual function and control of eye the pons and the movements. cerebellum. TEGMENTUM – is the division of the PONS –. It is involved in the control of mesencephalon ventral (lower) to the tectum. breathing, communication between different It promotes cardiorespiratory functions and parts of the brain, and sensations such as airway-protective reflexes. hearing, taste, and balance. FOREBRAIN CEREBELLUM – receives information - controls body from the sensory systems, the spinal cord, temperature, reproductive and other parts of the brain and then regulates functions, eating, sleeping, motor movements. and the display of MIDBRAIN emotions. - a small but important part of the DIENCEPHALON brain that connects - is situated between the telencephalon and the forebrain and the midbrain. hindbrain. - Composed of two structures: THALAMUS AND HYPOTHALAMUS BIOPSYCH -KML CHAPTER 2.2 THALAMUS FRONTAL LOBE - Is a large mass of grey - The frontal lobes make up the largest part matter in the dorsal part of the cortex. of the diencephalon of the - Their central brain. functions are - relays motor and to process sensory signals to the information cerebral cortex. It also relating to memory, planning, decision regulates sleep, alertness, and wakefulness. making, goal setting, and creativity. - The HYPOTHALAMUS frontal lobes also contain the primary motor - It exerts its effects in cortex that regulates muscular movements. part by regulating the TEMPORAL LOBE release of hormones - located on the side from the pituitary of the cerebrum, is gland which dangles responsible for from it on the ventral processing auditory surface of the brain. information. - It plays an important role in the regulation PARIETAL LOBE of several motivated behaviors (e.g., eating, sleep, and sexual behavior). TELENCEPHALON (CEREBRUM) - The largest division of the human brain. - responsible for the integration of complex sensory and neural functions - Located at the top of the brain in the and the initiation cerebrum are responsible for the sense of and coordination of touch, and they help to determine body voluntary activity in the body. position and integrate visual information. - The parietal lobes have anterior (front) and posterior (rear) sections. BIOPSYCH -KML CHAPTER 2.2 OCCIPITAL LOBE HIPPOCAMPUS - are primarily - is the brain structure concerned with responsible for memory processing visual of the immediate past. information. - The occipital lobe FORNIX also is known as the visual cortex. - is a C-shaped bundle CEREBRAL CORTEX of nerve fibers in the - The outermost layer of brain that acts as the the brain containing major output tract of gray matter. the hippocampus. - Responsible for many - Damage to the fornix has been associated higher order functions with anterograde amnesia—inability to like language and create new memories. information processing. CINGULATE CORTEX THE LIMBIC SYSTEM AND THE - it is involved in BASAL GANGLIA processing emotions and LIMBIC SYSTEM behavior regulation. It also - Is involved in the regulation of motivated helps to regulate and emotional behaviors autonomic motor function. - process your memory, thoughts and SEPTUM motivations, then tell your body how to - a wall or membrane that separates two respond. spaces or masses of soft tissue AMYGDALA - hippocampus and hypothalamus - is involved in the BASAL GANGLIA control of emotion, - responsible primarily survival instincts for motor control, as and memory. well as other roles such - The amygdala’s as motor learning, function is to assess executive functions and behaviors, and the harmfulness of sensory inputs. emotions. BIOPSYCH -KML CHAPTER 2.2 CAUDATE NUCLEUS SPINAL CORD - Means “tail-like’ - The caudate nucleus is a C-shaped structure. - It’s responsible for processing visual information, movement, and memory. PUTAMEN - the outer part of the nucleus of the brain. - Is a long, thin bundle of nervous tissue and. - is involved in motor support cells connected to the brain and learning, speech located along your back and neck. articulation, language functions, reward, - Receives and transmits electric signals cognitive functioning, and addiction. throughout the entire body and then back to STRIATUM the brain. - decision making - The spinal cord is protected by the functions, such as motor vertebrae, which are bones running down control, emotion, habit your back, and also by cerebral spinal fluid, formation, and reward. which help to cushion the nerve tissue. Cervical - consists of the first seven GLOBUS PALLIDUS vertebrae in your spine. It provides support for the weight of your head ,surround and - control conscious protects your spinal cord, and allows for a and proprioceptive wide range of head motions. movements. (your Thoracic - is the middle section of your body's ability to sense spine. It starts at the base of your neck and movement, action, ends at the bottom of your ribs. It consists of and location). 12 vertebrae. It is especially rigid and stable, making it the least common area of injury. BIOPSYCH -KML CHAPTER 2.2 Lumbar - consists of the five vertebrae in MENINGES, VENTRICLES, AND your lower back. It provides support for the CEREBROSPINAL FLUID weight of your body, surrounds and protects 3 LAYERS OF MENINGES your spinal cord, and allows for a wide range - Are layers of tough of body motions. and connective Sacrum - has five segments fused together tissue that protect into one large bone. Nerves that leave the and cover the brain spine in this area help control the bowels and and spinal cord. bladder and provide sensation to the crotch area. A. DURA MATER - the thickest and TWO DIFFERENT AREAS OF SPINAL outermost of the three meninges surrounding CORD the brain and spinal cord GRAY MATTER B. ARACHNOID MATER - Spider - is a tissue in the brain and spinal cord that weblike membrane - the middle of the three processes and interprets information. membranes covering the brain and spinal - it plays a significant role in mental cord. It is separated from the pia mater by the functions, memory, emotions and movement. ‘subarachnoid cavity” which is filled with is composed largely of unmyelinated axons “cerebrospinal fluid.” WHITE MATTER C. PIA MATER - is the meningeal envelope - it connects regions that send and receive that firmly adheres to the surface of the brain signals, affecting the ability to focus and and spinal cord. It is a very thin membrane learn, solve problems, and stay balanced composed of fibrous tissue covered on its when walking outer surface by a sheet of flat cells - is composed largely of myelinated axons CEREBRAL VENTRICLES - Are the four large internal chambers of the brain; the two lateral ventricles, the third ventricle, and the fourth ventricle. - are responsible for the production, transport and removal of cerebrospinal fluid. BIOPSYCH -KML CHAPTER 2.2 CENTRAL CANAL 1. SOMATIC NERVOUS SYSTEM - also known as ependymal canal, is the (SNS) “VOLUNTARY cerebrospinal fluid-filled space that runs - The somatic nervous system derives its longitudinally through the length of the entire name from the Greek word soma, which spinal cord. means "body." -The central canal is continuous with the - Is the part of the PNS that responsible for ventricular system of the brain. carrying sensory and motor information to CEREBROSPINAL FLUID (CSF) and from the central nervous system. - is a clear, colorless body fluid found in the - It is composed of afferent and efferent brain and spinal cord. nerves - Fills the subarachnoid space, the central A. AFFERENT NERVES canal of the spinal cord, and the cerebral - Also known as sensory neurons ventricles of the brain - Carry sensory signals from the skin, skeletal BLOOD-BRAIN BARRIER muscles, joints, eyes, ears, and so on, to the - Composed of tightly packed cells of the central nervous system brain’s blood vessel walls B. EFFERENT NERVES - Impedes the passage of many toxic - Also known as motor neurons substances from the blood into the brain - Carry motor signals from the central B. PERIPHERAL NERVOUS nervous system to the skeletal muscles. SYSTEM (PNS) 2. AUTONOMIC NERVOUS SYSTEM - is the division of the nervous system (ANS) “INVOLUNTARY” containing all the nerves that lie outside of the central nervous system (CNS). - is the part of the peripheral nervous system - The primary role of the PNS is to connect that regulates the body’s internal the CNS to the organs, limbs, and skin. environment. - It is composed of afferent nerves that carry TWO DIVISIONS OF PNS sensory signals from internal organs to the Somatic Nervous System (SNS) CNS and efferent nerves that carry motor Autonomic Nervous System (ANS) signals from the CNS to internal organs. BIOPSYCH -KML CHAPTER 2.2 TWO KINDS OF EFFERENT FUNCTIONS OF SYMPATHETIC AND NERVES UNDER ANS PARASYMPATHETIC SYSTEMS A. Sympathetic Nervous System (makes SYMPATHETIC SYSTEM you alert) - Stimulate, organize, and mobilize energy B. Parasympathetic Nervous System resources in threatening situations (makes you calm) - Sympathetic changes are indicative of A. SYMPATHETIC NERVOUS psychological arousal SYSTEM PARASYMPATHETIC SYSTEMS - Act to conserve energy - Are those autonomic - Indicative of psychological relaxation motor nerves that project from the CNS in the lumbar (small of the back) and thoracic (chest area) regions of the spinal cord - Regulates the flight or fight responses. B. PARASYMPATHETIC NERVOUS SYSTEM - Are those autonomic motor nerves that project from the brain and sacral (lower back) region of the spinal cord - Regulates the rest or digest response BIOPSYCH -KML