16.9 Glossary

Abstract reasoning (ăb-străkt RĒ-zŏn-ĭng): The ability to analyze information, detect patterns and relationships, and solve problems on a complex, intangible level. (Chapter 16.5)

Alzheimer’s disease (ălts-hī-mĕrz dĭ-zēz) (AD): A progressive neurodegenerative disorder characterized by memory loss, language deterioration, and impaired ability to mentally manipulate visual information. (Chapter 16.6)

Amyotrophic lateral sclerosis (ā-mī-ō-TRŎF-ik LĂT-ĕr-ăl sklĕ-RŌ-sĭs) (ALS): A progressive neurodegenerative disease that affects nerve cells in the brain and spinal cord, causing muscle weakness and atrophy. (Chapter 16.6)

Anesthesia (an-ĕs-THĒ-zhă): The loss of sensation or feeling in a part or all of the body, often induced for medical procedures. (Chapter 16.5)

Aphasia (ă-FĀ-zh-ē-ă): A condition characterized by either partial or total loss of the ability to communicate verbally or using written words. (Chapter 16.5)

Attention deficit hyperactivity disorder (ă-tĕn-shŭn dĕf-ĭ-sĭt hī-pĕr-ăk-tĭv-ĭ-tē dĭs-ôr-dĕr) (ADHD): A neurodevelopmental disorder characterized by a persistent pattern of inattention and/or hyperactivity-impulsivity that interferes with functioning or development. (Chapter 16.6)

Axon (ăk-sŏn): The long, slender projection of a nerve cell that typically conducts electrical impulses away from the neuron’s cell body. (Chapter 16.4)

Brain stem (brān stĕm): The central trunk of the brain, consisting of the medulla oblongata, pons, and midbrain, and continuing downward to form the spinal cord. (Chapter 16.4)

Broca’s area (brō-kăz ăr-ē-ă): A region in the frontal lobe of the brain with functions linked to speech production. (Chapter 16.4)

Carotid endarterectomy (kă-rŏt-ĭd ĕnd-ăr-tĕr-ĔK-tŏ-mē): A surgical procedure to remove plaque from the carotid arteries and restore blood flow to the brain, often used to prevent stroke. (Chapter 16.7)

Carpal tunnel syndrome (KÄR-păl TŬN-ĕl SĬN-drōm): A condition caused by compression of the median nerve within the carpal tunnel of the wrist, leading to pain, numbness, and tingling in the hand. (Chapter 16.6)

Cell body (sĕl bŏd-ē): The spherical part of the neuron that contains the nucleus and connects to the dendrites and axon. (Chapter 16.4)

Central nervous system (SEN-trăl NŬR-vŭs SĬS-tĕm) (CNS): The part of the nervous system consisting of the brain and spinal cord, responsible for processing and transmitting information throughout the body. (Chapter 16.4)

Cerebellum (sĕr-ĕ-bĕl-ŭm): A major structure of the hindbrain that is responsible for fine motor coordination, balance, equilibrium, and muscle tone. (Chapter 16.4)

Cerebral angiography (SĚR-ē-brăl ăn-jē-ŎG-ră-fē): A diagnostic imaging technique that uses X-rays to visualize blood flow in the arteries and veins in the brain. (Chapter 16.7)

Cerebral cortex (sĕ-RĒ-brăl KÔR-tĕks): The outer layer of the cerebrum, playing a key role in memory, attention, perception, cognition, awareness, thought, language, and consciousness. (Chapter 16.4)

Cerebrovascular accident (sĕr-ĕ-brō-VĂS-kyŭ-lăr ăk-sĭ-dĕnt) (CVA): Also known as a stroke, it is the sudden death of brain cells due to lack of oxygen, caused by blockage of blood flow or rupture of an artery in the brain. (Chapter 16.6)

Cerebrum (sĕ-RĒ-brŭm): The largest part of the brain, responsible for voluntary muscular activity, vision, speech, taste, hearing, thought, and memory. (Chapter 16.4)

Chronic traumatic encephalopathy (KRŎN-ĭk trô-măt-ĭk ĕn-sĕf-ăl-ŌP-ă-thē) (CTE): A brain condition associated with repeated blows to the head and repeated episodes of concussion. (Chapter 16.6)

Concussion (kŏn-KŬSH-ŭn): A type of traumatic brain injury caused by a blow to the head or body, a fall, or another injury that jars or shakes the brain inside the skull. (Chapter 16.6)

Cranial nerves (krā-nē-ăl nĕrvz): The 12 pairs of nerves that emerge directly from the brain, as opposed to spinal nerves, with functions largely concerning the head and neck. (Chapter 16.4)

Dendrites (dĕn-drīts): Extensions of a neuron that receive signals from other neurons and transmit them toward the cell body. (Chapter 16.4)

Dura mater (dŏŏ-ră mā-tĕr): The thick, tough outer layer of the meninges surrounding the brain and spinal cord. (Chapter 16.4)

Electroconvulsive therapy (ē-lek-trō-kŏn-VŬL-sĭv THĔR-ă-pē) (ECT): A medical treatment most commonly used for patients with severe major depression or bipolar disorder that has not responded to other treatments, involving brief electrical stimulation of the brain while the patient is under anesthesia. (Chapter 16.7)

Electroencephalogram (ĕ-lek-trō-ĕn-SĔF-ă-lŏ-gram) (EEG): A test that detects electrical activity in the brain using small, flat metal discs (electrodes) attached to the scalp. (Chapter 16.7)

Electromyogram (ē-lĕk-trō-MĪ-ŏ-gram) (EMG): A diagnostic test that measures the electrical activity of muscles to help diagnose muscle and nerve disorders. (Chapter 16.7)

Expressive aphasia (eks-PRĒS-ĭv ă-FĀ-zh-ē-ă): A type of aphasia where a person knows what they want to say but has difficulty communicating it to others. (Chapter 16.5)

Frontal lobe (FRŎN-tăl lōb): A region of the cerebral cortex associated with reasoning, motor skills, higher-level cognition, and expressive language. (Chapter 16.4)

Hematoma (hēm-ă-TŌ-mă): A solid swelling of clotted blood within the tissues, often caused by an injury. (Chapter 16.6)

Hypothalamus (hī-pō-THAL-a-mus): A region of the forebrain below the thalamus that coordinates both the autonomic nervous system and the activity of the pituitary, controlling body temperature, thirst, hunger, and other homeostatic systems. (Chapter 16.4)

Intracranial pressure (ĭn-tră-KRĀ-nē-ăl PRĔSH-ŭr): Pressure inside the skull and thus in the brain tissue and cerebrospinal fluid, usually in the context of illness or injury. (Chapter 16.6)

Judgment (JŬJ-mĕnt): The ability to make considered decisions or come to sensible conclusions. (Chapter 16.5)

Language (LĂNG-gwij): The method of human communication, either spoken or written, consisting of the use of words. (Chapter 16.5)

Lumbar puncture (LŬM-băr PŬNK-chŭr): A medical procedure where a needle is inserted into the lower part of the spinal column to collect cerebrospinal fluid for diagnostic testing or to relieve pressure. (Chapter 16.7)

Memory (MĔM-ŏ-rē): The faculty by which the mind stores and remembers information. (Chapter 16.5)

Meninges (mĕn-ĭn-jēz): The three membranes that envelop the brain and spinal cord, providing protection for these structures. (Chapter 16.4)

Multiple sclerosis (MŬL-tĭ-pl sklĕ-RŌ-sĭs) (MS): An autoimmune disease that affects the brain and spinal cord, leading to demyelination, inflammation, and scarring, resulting in a range of symptoms including physical, mental, and sometimes psychiatric problems. (Chapter 16.6)

Myelin (mī-ĕ-lĭn): The protective fatty layer that wraps around the nerve fibers (axons), facilitating the fast transmission of electrical signals. (Chapter 16.4)

Neurologist (nū-RŎL-ō-jĭst): A physician who specializes in the diagnosis and treatment of disorders of the nervous system, brain, spinal cord, nerves, and muscles. (Chapter 16.7)

Neurology (noo-ROL-ŏ-jē): The study of the nervous system. (Chapter 16.7)

Neurons (nŭr-ŏns): Nerve cells that are the basic building blocks of the nervous system, responsible for transmitting information throughout the body. (Chapter 16.4)

Neurosurgeons (nū-RŎ-sŭrj-ŭnz): Surgeons who specialize in surgery on the nervous system, including the brain and spinal cord. (Chapter 16.7)

Neurotransmitter (nŭr-ō-trăns-mĭt-ĕr): Chemical substances that transmit nerve signals across a synapse from one neuron to another. (Chapter 16.4)

Occipital lobe (ŏk-SĬP-ĭ-tăl lōb): The rearmost lobe in each cerebral hemisphere of the brain, responsible for processing visual information. (Chapter 16.4)

Orientation (or-ē-ĕn-TĀ-shŏn): The patient’s awareness of their immediate circumstances (i.e., being oriented to person, place, and time). (Chapter 16.5)

Paresthesia (par-es-THĒ-zh(ē-)ă): An abnormal sensation, such as tingling, pricking, or numbness, typically with no apparent physical cause. (Chapter 16.5)

Parietal lobe (pă-rī-ĕ-tăl lōb): The upper middle lobe of the cerebrum, involved in processing sensory information such as touch, temperature, and pain. (Chapter 16.4)

Parkinson’s disease (pär-kĭn-sŏnz dĭ-zēz) (PD): A progressive nervous system disorder that affects movement, often including tremors, muscle rigidity, and changes in speech and gait. (Chapter 16.6)

Peripheral nervous system (pĕ-rĬF-ĕr-ăl NŬR-vŭs SĬS-tĕm) (PNS): The part of the nervous system outside the CNS, consisting mainly of the nerves that extend from the brain and spinal cord. (Chapter 16.4)

Photophobia (fō-tō-FŌ-bē-ă): An extreme sensitivity to light, often causing discomfort or pain in the eyes. (Chapter 16.6)

Post-traumatic stress disorder (pōst-TRŌ-măt-ĭk strĕs dĭs-ôr-dĕr) (PTSD): A mental health condition triggered by experiencing or witnessing a terrifying event, characterized by flashbacks, nightmares, severe anxiety, and uncontrollable thoughts about the event. (Chapter 16.6)

Prefrontal cortex (prē-FRŎN-tăl KÔR-tĕks): The front part of the frontal lobe, involved in complex behaviors such as planning, and contributing to personality development. (Chapter 16.4)

Psychiatrist (sī-KĪ-ă-trĭst): A medical doctor specializing in the diagnosis, prevention, study, and treatment of mental disorders, including prescribing medication. (Chapter 16.7)

Psychiatry (sī-KĪ-ă-trē): The medical specialty devoted to diagnosing, preventing, studying, and treating mental disorders. (Chapter 16.7)

Psychologists (sī-KŎL-ō-jĭstz): Professionals who study cognitive, emotional, and social processes and behavior by observing, interpreting, and recording how individuals relate to one another and to their environments. (Chapter 16.7)

Psychology (sī-KOL-ŏ-jē): The study of the mind and its functions, especially those affecting behavior. (Chapter 16.7)

Receptive aphasia (rĭ-SEP-tĭv ă-FĀ-zh-ē-ă): A form of aphasia where individuals have trouble understanding spoken or written language. (Chapter 16.5)

Sciatica (sī-ăt-ĭ-kă): Pain affecting the back, hip, and outer side of the leg, caused by compression or irritation of the sciatic nerve. (Chapter 16.4)

Seizure (sē-zhŭr): An uncontrolled electrical disturbance in the brain, which can cause changes in behavior, movements, feelings, and levels of consciousness. (Chapter 16.6)

Sensorium (sĕn-SAWR-ē-ŭm): The sensory apparatus or faculties considered as a whole. (Chapter 16.5)

Skull fracture (skŭl FRĂK-chŭr): A break in one or more of the bones in the skull, often caused by a blow to the head. (Chapter 16.6)

Social workers (SŌ-shăl WŬR-kĕrz): Professionals who provide a wide range of services to help people cope with and overcome challenges in their everyday lives, including mental health and substance abuse counseling. (Chapter 16.7)

Speech (spēch): The expression of thoughts and feelings by articulating sounds. (Chapter 16.5)

Spinal cord (spī-năl kôrd): The cylindrical bundle of nerve fibers and associated tissue enclosed in the spine, connecting nearly all parts of the body to the brain. (Chapter 16.4)

Spinal nerves (spī-năl nĕrvz): Nerves that originate in the spinal cord and branch out to provide motor and sensory functions to the body. (Chapter 16.4)

Subarachnoid hemorrhage (sŭb-ă-răk-NOYD HĔM-ŏr-ĭj): A type of stroke caused by bleeding into the space surrounding the brain, leading to sudden severe headache and other symptoms. (Chapter 16.6)

Subdural hematoma (sŭb-DŪ-răl hĕm-ă-TŌ-mă): A type of hematoma, usually associated with traumatic brain injury, involving bleeding in the outermost meningeal layer, just under the skull. (Chapter 16.6)

Synapse (sĭn-ăps): The junction between two nerve cells, consisting of a minute gap across which impulses pass by diffusion of a neurotransmitter. (Chapter 16.4)

Temporal lobe (tĕm-pŏ-răl lōb): A region of the cerebral cortex responsible for processing auditory information and is also involved in memory storage. (Chapter 16.4)

Thalamus (thăl-ă-mŭs): A small structure within the brain located just above the brain stem between the cerebral cortex and the midbrain with multiple functions, including relaying sensory and motor signals to the cerebral cortex. (Chapter 16.4)

Transient ischemic attacks (trăn-zhĕnt ĭs-KĒ-mĭk ă-tăks) (TIAs): Often called a “mini-stroke,” a temporary period of symptoms similar to those of a stroke, indicating a high risk of a full-blown stroke in the future. (Chapter 16.6)

Traumatic brain injury (trô-măt-ĭk brān ĬN-jŭ-rē) (TBI): A form of brain injury caused by a blow, jolt, or other traumatic injury to the head or body, causing temporary or permanent damage. (Chapter 16.6)

Vagus nerve (VĀ-gŭs nĕrv): A cranial nerve that extends from the brain stem to the abdomen, playing critical roles in the heart, lungs, and digestive tract functioning. (Chapter 16.4)

Ventricles (vĕn-trĭ-kŭls): Hollow, fluid-filled cavities within the brain that help to protect the brain and reduce its weight. (Chapter 16.4)

Wernicke’s area (wĕr-nĭk-kēz ăr-ē-ă): A region of the brain that is important for language development, located in the temporal lobe. (Chapter 16.4)