PTHA 1321: Chapter 14 - Acute Neurologic Disorders Flashcards

These flashcards cover the vocabulary and key concepts for Chapter 14: Acute Neurologic Disorders, including neuroanatomy, diagnostic scales, and specific pathologies like CVA, SCI, and TBI.

Dura mater

The outer membrane layer lining the skull as part of the meninges.

Arachnoid mater

The middle layer of the meninges, separated from the dura mater by the subdural space.

Pia mater

The inner layer of the meninges that directly covers the brain.

Subarachnoid space

The space between the arachnoid and pia mater that contains Cerebrospinal fluid (CSF), cerebral arteries, and veins.

Cerebrospinal fluid (CSF)

A clear and almost colorless fluid formed in the choroid plexus in the ventricles that provides a cushion for the brain and spinal cord.

Blood-brain barrier (BBB)

A protective mechanism provided by brain capillaries where endothelial cells are joined tightly to limit the passage of damaging material.

Broca’s area

Located in the frontal lobe of the left hemisphere; responsible for motor or expressive speech.

Wernicke’s area

Located in the temporal lobe of the left hemisphere; responsible for comprehending language received.

Limbic system

A collection of structures within the brain (including the amygdala, hippocampus, and hypothalamus) responsible for emotional reactions and feelings.

Thalamus

A part of the diencephalon that sorts and relays incoming sensory impulses to appropriate areas of the brain.

Hypothalamus

A structure that maintains homeostasis by regulating temperature, sleep cycles, stress response, emotional response, and food/fluid intake.

Reticular formation

A part of the brainstem that controls arousal or awareness.

Cerebellum

Often called the 'little brain,' it is dorsal to the pons and medulla and is responsible for coordination, posture, and balance.

Circle of Willis

A vascular structure at the base of the brain that connects the anterior and posterior circulatory systems.

Vagus nerve (CN X)

A cranial nerve that innervates the viscera and contains parasympathetic fibers.

Dermatome

An area of sensory innervation of the skin by a specific spinal nerve.

Myotome

An area of muscle innervated by a specific spinal nerve.

Supratentorial lesions

Lesions located in the cerebral hemisphere above the tentorium that cause dysfunction in an isolated area.

Infratentorial lesions

Lesions located in the brainstem or below the tentorium that cause widespread impairment and can impair consciousness even if small.

Glasgow Coma Scale

A clinical scale used to assess consciousness based on eye opening (1-4), verbal response (1-5), and motor response (1-6).

Vegetative State

A state resulting from diffuse brain damage characterized by loss of awareness and mental abilities while respiratory, CV, and autonomic functions continue.

Locked-in syndrome

A condition where the individual is aware and able to think but is paralyzed and unable to communicate, except sometimes through eye movements.

Upper Motor Neuron (UMN) Syndrome

Damage in the frontal lobe or corticospinal tracts characterized by hyperreflexia, spastic paralysis, hypertonia, and minimal atrophy.

Lower Motor Neuron (LMN) Syndrome

Damage in the anterior horn of the SC or CN nuclei characterized by hyporeflexia, flaccid muscles, hypotonia, and pronounced atrophy.

Decorticate posturing

Abnormal motor response involving rigid UE flexion, adduction, and internal rotation with LE extensor response, indicating damage above the midbrain.

Decerebrate posturing

Abnormal motor response involving UE and LE extensor responses, indicating severe damage of the diencephalon or midbrain.

Homonymous hemianopia

Vision loss from the medial half of one eye and the lateral half of the other eye.

Aphasia

A language deficit which can be expressive (Broca’s), receptive (Wernicke’s), or global (combination of both).

Dysarthria

The inability to articulate words clearly.

Agnosia

the loss of recognition or association, such as the inability to recognize objects (visual agnosia).

Intracranial Pressure (ICP)

The pressure inside the skull, normally between $5-15\,mmHg$, which can increase due to edema, tumors, or hemorrhage.

Hereditary risk of Cerebrovascular Disorders

These disorders are more common in males and are the leading cause of disability in the U.S.

Transient Ischemic Attack (TIA)

A 'mini-stroke' caused by a temporary decrease in blood flow to a specific area, with recovery typically occurring within $24$ hours.

Cerebrovascular Accident (CVA)

Infarction or necrosis of brain tissue due to lack of blood, caused by thrombosis, embolism, or hemorrhage.

Aneurysm

A localized dilation in an artery at a site of weakness, commonly occurring at bifurcations in the circle of Willis.

Nuchal rigidity

A hyperextended, stiff neck, often a sign of meningitis.

Encephalitis

A viral infection of the meninges and white matter often spread by mosquitos or ticks, leading to nerve cell degeneration.

Post-polio syndrome

A condition occurring years after initial polio infection where spared motor neurons become overused and stressed, leading to muscle weakness and atrophy.

Guillain-Barre Syndrome

A demyelinating disorder of peripheral nerves causes ascending motor paralysis from the distal to proximal regions.

Closed Head Injury (CHI)

A brain injury where the skull remains intact but blood vessels may rupture and the brain is injured by hitting a hard surface.

Coup injury

Brain injury occurring at the area of direct impact.

Countrecoup injury

Brain injury occurring on the opposite side of the force of impact due to the brain rebounding against the skull.

Diffuse Axonal Injury (DAI)

Injury caused by acceleration or deceleration forces that cause axons to twist and tear.

Extradural hematoma (EDH)

Bleeding between the dura and the skull, often caused by a tear of the middle meningeal artery.

Spinal Shock

An initial period after SCI where conduction of impulses stops, resulting in flaccid paralysis and no reflexes below the level of injury.

Autonomic Dysreflexia

A serious complication for injuries at $T6$ or above, where a sensory stimulus below the lesion triggers an uncontrolled sympathetic reflex response.