Neurological System Notes (NURS 326)

Vocabulary flashcards covering key nervous system terms, pain concepts, fever/fever physiology, brain injuries, and cerebrovascular accidents from the lecture notes.

Central Nervous System

Brain and spinal cord; the body's main control and information-processing center.

Peripheral Nervous System

Nerves outside the CNS (cranial and spinal nerves) that connect the CNS to the rest of the body.

Somatic Nervous System

Voluntary motor and sensory pathways that control skeletal muscles and external senses.

Autonomic Nervous System

Involuntary control of visceral functions; subdivides into sympathetic and parasympathetic divisions.

Sympathetic Nervous System

prepares the body for stress (fight or flight); increases heart rate and blood flow to muscles.

Parasympathetic Nervous System

Conserves energy and promotes rest-and-digest activities.

Neuron

Primary cell of the nervous system that conducts electrical impulses.

Neuroglial Cells

Support cells in the CNS that assist neurons; include Schwann cells in the PNS.

Schwann Cells

Glial cells in the peripheral nervous system that form the myelin sheath.

Myelin Sheath

Insulating layer around axons that speeds electrical conduction.

Synapse

Junction between neurons where neurotransmitters cross to transmit signals.

Neurotransmitters

Chemicals that transmit signals across a synapse; examples include ACh, norepinephrine, serotonin, dopamine, GABA, glutamate, and endorphins.

Acetylcholine

Neurotransmitter involved in NMJ transmission and many CNS roles.

Norepinephrine

Neurotransmitter involved in arousal and autonomic responses.

Serotonin

Neurotransmitter involved in mood regulation and other CNS functions.

Dopamine

Neurotransmitter involved in movement, reward, and motivation.

Histamine

Neurotransmitter involved in wakefulness and inflammatory responses.

GABA

Gamma-aminobutyric acid; the primary inhibitory neurotransmitter in the CNS.

Glutamate

Primary excitatory neurotransmitter in the CNS.

Endorphins

Endogenous opioid peptides that modulate pain and mood.

Forebrain

Anterior brain region responsible for perception, thought, memory, language, and voluntary movement.

Midbrain

Relays motor and sensory information and houses auditory/visual reflex centers.

Hindbrain

Coordinates movement, balance, and vital autonomic functions; includes the brainstem and cerebellum.

Dura Mater

Outermost protective meningeal layer surrounding the brain.

Arachnoid Mater

Middle meningeal layer with a web-like structure; cushions the CNS.

Pia Mater

Innermost meningeal layer closely covering brain and spinal cord.

Cerebrospinal Fluid (CSF)

Fluid that cushions the brain and spinal cord and circulates nutrients.

Cranial Nerves

Twelve pairs of nerves that originate in the brain and control head/neck functions and beyond.

Spinal Nerves

Thirty-one pairs of nerves that emerge from the spinal cord and innervate the body.

Hypothalamus

Brain region that regulates temperature and autonomic functions.

Temperature Regulation

Control of heat production, conservation, and loss, primarily via the hypothalamus.

Fever

Elevation of body temperature due to a shifted hypothalamic set point by pyrogens.

Pyrogen

Substance that causes fever by resetting the hypothalamic set point.

Afferent Pathways

Nerve pathways that carry sensory signals toward the brain.

Nociceptors

Pain receptors in peripheral nerves that detect tissue damage.

Thalamus

Brain structure that processes and localizes sensory input, including pain.

Efferent Pathways

Nerve pathways that carry motor responses from the brain to the body.

A-fibers

Large, myelinated fibers that transmit fast, sharp pain.

C-fibers

Small, unmyelinated fibers that transmit slow, dull pain.

Gate Control Theory

Concept that non-painful input can close the neural “gate” to painful input, reducing perception of pain.

Pain Threshold

Lowest stimulus intensity perceived as painful.

Pain Tolerance

Maximum level of pain a person is able to endure.

Endogenous Opioids

Internal opioid peptides that inhibit pain signaling and can affect mood.

Acute Pain

Short-term pain from injury or disease; protective and usually resolves within 3 months.

Somatic Acute Pain

Acute pain from skin, joints, or muscles; well localized and sharp/throbbing.

Visceral Acute Pain

Acute pain from internal organs; crampy, deep, often poorly localized.

Referred Pain

Pain felt in a location distant from the site of origin due to shared pathways.

Chronic Pain

Pain lasting 3 months or longer; may be hard to treat and affect function and mood.

Transient Ischemic Attack (TIA)

Temporary focal neurological deficit due to brief cerebral ischemia; resolves within 24 hours; warning sign for stroke.

Cerebral Infarction

Brain tissue death due to loss of blood supply.

Thrombotic Stroke

Ischemic stroke from thrombus formation in cerebral arteries, often with atherosclerosis.

Embolic Stroke

Ischemic stroke caused by an embolus that travels to cerebral vessels.

Hemorrhagic Stroke

Stroke due to bleeding in the brain, increasing intracranial pressure.

Epidural Hematoma

Bleeding between the dura mater and the skull.

Subdural Hematoma

Bleeding between the dura and arachnoid mater.

Subarachnoid Hemorrhage

Bleeding into the subarachnoid space surrounding the brain.

Intracerebral Hemorrhage

Bleeding within brain tissue itself.

Increased Intracranial Pressure (ICP)

Life-threatening rise in pressure inside the skull that can compress brain tissue.

Cerebral Perfusion Pressure (CPP)

CPP = mean arterial pressure − intracranial pressure; adequate CPP is essential for brain viability.

Cushing's Triad

Signs of rising ICP: hypertension with wide pulse pressure, bradycardia, and irregular or slowed respiration.

Decorticate Posturing

Abnormal flexion of the arms with stiff elbows, indicating cortical injury.

Decerebrate Posturing

Rigid extension of arms/legs, indicating brainstem injury.

Doll's Eye Reflex

Oculocephalic reflex; eyes move to maintain forward gaze when head is turned; abnormal when absent.

Herniation

Displacement of brain tissue due to high ICP; types include falx (cingulate) herniation, temporal herniation, and brainstem herniation.

Cerebrovascular Accident (CVA)

Stroke; sudden loss of brain function due to disturbance in blood supply.

Risk Factors for CVA

Age, hypertension, smoking, diabetes, carotid stenosis, hyperlipidemia, family history, African American race.