Chapter 1 Exam retake

Neurogenic Communication Disorder (NCD)

Result from damage to the CNS, PNS, or both, leading to deficits in communication, cognition, language, and behavior. Common causes include stroke, traumatic brain injury (TBI), surgical trauma, degenerative disorders, and infectious diseases.

Types of Neurogenic Communication Disorders

NCD includes aphasia, dysarthrias, apraxia of speech, communication problems from right hemisphere deficits, traumatic brain injury (TBI), and dementia.

Treatment Settings for NCD

Treatment settings include skilled nursing facilities, acute care facilities, rehabilitation facilities, outpatient rehab, home health care, hospice care, children's hospitals, and schools.

NCD Targeted by SLP

SLP targets speech, language, and cognition, including subcategories of each.

Cognition

The ability to think, acquire, and process knowledge. Important for supporting effective communication.

Cognitive Abilities Important for Communication

Abilities like arousal, attention, orientation, problem solving, inferencing, and executive functions are crucial for communication.

Language

An agreed-upon set of symbols used to communicate. The brain selects the appropriate symbols to convey thoughts.

Expressive vs. Receptive Language

Language abilities are divided into expressive (producing language) and receptive (understanding language) abilities.

Speech

Refers to the sounds made by the vocal and articulatory structures to produce verbal language and express thoughts.

Relationship Between Deficits in Speech, Language, and Cognition

Deficits in these areas can occur independently or together. One area may be affected without others, but language and cognitive deficits often co-occur and interact.

Normal Aging and Communication Changes

Mild changes in speech, language, and cognition happen naturally with aging, not due to disease, and don’t disrupt daily life.

Cognitive Declines with Aging

Aging may cause slight cognitive declines in selective attention, complex multitasking, and types of memory (short-term, episodic, declarative, working memory). However, orientation, long-term memory, and executive functions remain intact.

Language and Aging

Language abilities may decline slightly in verbal processing, reading, word-finding, and comprehension. Functional communication remains intact, and speech/voice changes subtly but don’t impact daily life or require therapy.

Evidence-Based Practice in SLP

Combines research, clinical expertise, and expert opinion to ensure effective, high-quality care. SLPs must stay current with the latest research to support therapy methods.

Neurons

Cells of the nervous system responsible for processing and transmitting information. They generate cognition, speech, and language, and send motor signals from the brain to the body and sensory signals from the body to the brain.

Neuroglia (Glial Cells)

Provide structural support and perform essential background functions in the nervous system.

Sensory Neurons

Carry information from sensory receptors to the brain or spinal cord for processing.

Motor Neurons

Send movement signals from the brain and spinal cord to the body.

Interneurons

Connect within the brain and focus on processing information rather than transmitting it.

Structure of a Neuron

A neuron consists of a cell body (soma), dendrites, and an axon. Dendrites extend from the soma to connect with other neurons, while the axon transmits signals

Oligodendrocytes

Glial cells in the CNS that produce the myelin sheath, a fatty covering that insulates axons and speeds up neural signals.

Astrocytes

Glial cells that provide structural support, form a barrier between neurons and the circulatory system, and create glial scars around CNS lesion sites to limit inflammation

Astrocytosis

The process where astrocytes form glial scars to limit inflammation.

Microglia

Immune cells in the CNS that remove waste, damaged neurons, and neural tangles, responding quickly to pathogens.

Schwann Cells

Produce the myelin sheath around motor and sensory neurons in the PNS.

Nervous System Divisions

The nervous system is divided into the CNS (brain and spinal cord) and the PNS (cranial and spinal nerves).

Brain Structure

The brain consists of the cerebrum, brainstem, and cerebellum. The cerebral cortex has folds (gyri and sulci) that maximize neural tissue in a limited space.

Gray and White Matter

Gray matter processes information and lacks myelin, while white matter transmits signals and contains association, commissural, and projection fibers.

Ventricular System

The brain’s ventricular system has four ventricles that produce and circulate cerebrospinal fluid (CSF), cushioning the brain, delivering nutrients, and removing waste

Longitudinal Fissure

Divides the cerebrum into right and left hemispheres, connected by the corpus callosum, a thick band of commissural fibers.

Right Hemisphere Functions

Processes nonverbal stimuli, such as facial expressions, body language, and prosody. Manages visuospatial processing and controls sustained and selective attention.

Left Hemisphere Functions

Primarily controls expressive and receptive language. Broca’s area handles expressive language, and Wernicke’s area handles receptive language.

Four Paired Lobes of the Cerebrum

• Frontal lobes – Control expressive/receptive language and motor movements.

• Parietal lobes – Process sensory information, including touch and proprioception.

• Temporal lobes – Handle memory and auditory processing.

• Occipital lobes – Receive and process visual information.

Central and Lateral Sulci

The central sulcus separates the frontal and parietal lobes, while the lateral sulcus separates the frontal/parietal lobes from the temporal lobes

Subcortex

Includes the brainstem, cerebellum, thalamus, basal ganglia, and limbic system, controlling automatic functions like heartbeat, breathing, and sleep-wake cycles.

Brainstem Functions

The brainstem (midbrain, pons, medulla) connects the brain to the spinal cord.

Cerebellum Functions

The cerebellum ensures smooth, coordinated movements and error control. It has two hemispheres connected by the vermis.

Thalamus Function

Located above the brainstem, the thalamus relays afferent signals to appropriate brain regions.

Basal Ganglia

Regulate motor movement, muscle tone, and inhibit unnecessary movements. Composed of the caudate nucleus, putamen, and globus pallidus.

Limbic System

Controls pleasure, mating, feeding behaviors, the fight-or-flight response, emotions, emotional memory, and motivation.

Spinal Cord Functions

Begins at the medulla, narrows at the conus medullaris, and transmits afferent (sensory) signals to the brain and efferent (motor) signals to the body.

Brain Oxygen Consumption

The brain consumes 25% of the body’s oxygen and glucose.

Blood Supply to the Brain

Blood supply comes through the internal carotid and basilar arteries. The circle of Willis connects the internal carotid and vertebral/basilar systems.

Spinal Nerves

The 31 paired spinal nerves connect the spinal cord to muscles, organs, and glands. The phrenic nerve controls the diaphragm.

Cranial Nerves

The 12 paired cranial nerves connect the head, face, and neck to the CNS. Important cranial nerves for speech include the optic, trigeminal, facial, glossopharyngeal, vagus, accessory, and hypoglossal nerves.

Etiology

The medical cause of a symptom or deficit. If the cause is unknown, it is called idiopathic.

Stroke (Cerebrovascular Accident - CVA)

Occurs when blood flow to the brain is interrupted by a clot or hemorrhage. It is classified into ischemic and hemorrhagic types.

Ischemic Stroke

Occurs when a blood vessel is blocked, depriving brain tissue of blood supply. Types include thrombotic, embolic, and transient ischemic attack (TIA).

Thrombotic Stroke

Caused by a thrombus (a clot forming inside a blood vessel) often due to atherosclerosis.

Embolic Stroke

Occurs when an embolus (a traveling clot or mass) lodges in a brain blood vessel, blocking blood flow.

Transient Ischemic Attack (TIA)

A temporary blockage that resolves within 24 hours. Multiple TIAs can lead to cognitive and language deficits and signal a larger stroke.

Hemorrhagic Stroke

Occurs when a blood vessel in the brain ruptures, leading to bleeding in or around the brain. Causes brain damage through blood supply interruption, direct tissue damage, or increased intracranial pressure.

Subarachnoid Hemorrhagic Stroke

Occurs when bleeding happens between the brain surface and the skull in the subarachnoid space

Intracerebral Hemorrhagic Stroke

Occurs when a blood vessel bursts inside the brain.

Aneurysm

An abnormal swelling or ballooning of an artery wall, often due to hypertension, disease, hereditary factors, or atherosclerosis. A ruptured aneurysm causes a hemorrhagic stroke.

Traumatic Brain Injury (TBI)

Resulting from external trauma such as a fall, car accident, or assault, TBI severity affects language and cognitive deficits depending on the areas and extent of brain damage.

Opioid Overdose

Opioid overdose suppresses autonomic respiration, causing anoxia or hypoxia in the brain, leading to brain injury.

Brain Tumor

Abnormal growth of cells in the brain. Tumors can be primary (originating in the brain) or secondary (spread from another part of the body). Malignant tumors are cancerous, and deficits depend on the tumor’s location and severity.

Surgical Trauma

Brain damage occurring during surgeries like tumor removal or hemorrhage repair, which can lead to acquired language and cognitive deficits.

Infections Affecting CNS and PNS

Infections can cause damage in the CNS and PNS, affecting speech, language, and cognition. Types include encephalitis, HIV/AIDS, Creutzfeldt-Jakob disease, syphilis, and poliomyelitis.

Encephalitis

Acute inflammation of the brain or spinal cord caused by a viral or bacterial infection. Symptoms vary based on the infection’s type and location.

HIV/AIDS

HIV causes AIDS, which can lead to neuro-AIDS (HIV/AIDS dementia) or HIV-associated neurocognitive disorder. Symptoms include difficulty learning, slow processing, disfluent speech, and reduced attention.

Creutzfeldt-Jakob Disease

Caused by prions, this disease leads to dementia with rapid onset, involuntary movements, and Alzheimer-like changes such as amyloid plaques.

Syphilis

A sexually transmitted disease that can lead to neurosyphilis, affecting the nervous system with symptoms such as meningitis, visual issues, facial weakness, and motor dysfunction.

Poliomyelitis

Caused by a virus, poliomyelitis affects the motor nerve tracks of the PNS, causing asymmetrical paralysis and diminished reflexes.

Seizures

Abnormal electrical discharges in the brain that can occur periodically.

Stages of a Seizure

• Aura: Warning signs before a seizure.

• Ictus: The main seizure event, often with loss of consciousness and convulsions.

• Postictus: The recovery period, with confusion and weakness.

• Interictal Period: The time between seizures.

• Status Epilepticus: Seizures occurring without an interictal period.

Types of Seizures

• Partial Seizures: Confined to one brain region.

• Simple Partial Seizures: The person remains conscious.

• Complex Partial Seizures: The individual experiences altered consciousness.

• Generalized Seizures: Affects the entire brain, leading to total loss of consciousness.

• Tonic-Clonic Seizures: Loss of consciousness with stiffening and convulsions.

• Petit Mal Seizures: Brief periods of loss of awareness, often in children

Optic nerve (CN II)

Transmits visual information

Trigeminal nerve (CN V)

A sensory-motor nerve that carries sensory signals from the face and motor commands to the jaw muscles; it has ophthalmic, maxillary, and mandibular branches.

Facial nerve (CN VII)

divides into temporal and zygomatic branches, which receive bilateral innervation, and buccal and mandibular branches, which receive unilateral innervation

Glossopharyngeal nerve (CN IX)

sensory-motor nerve that provides sensory input from the posterior one-third of the tongue and motor control for pharyngeal muscles involved in swallowing.

Vagus nerve (CN X)

Sensory-motor nerve with multiple branches:

Pharyngeal plexus – Controls muscles of the soft palate and pharynx.

Superior laryngeal nerve – Has intrinsic and extrinsic branches affecting the larynx.

Recurrent laryngeal nerve – Innervates intrinsic muscles of the larynx, essential for voice production.

Accessory nerve (CN XI)

• motor-only nerve with two parts:

• Cranial portion – Works with the vagus nerve to control the larynx, pharynx, and velum.

• Spinal portion – Innervates shoulder muscles.

Hypoglossal nerve (CN XII)

a motor nerve that controls intrinsic and extrinsic tongue muscles, essential for speech and swallowing.