CH 10: The Nervous System and Mental Health

Neurologist

Medical doctor specializing in disorders of the nervous system.

Psychiatrist

Medical doctor who diagnoses and treats mental disorders.

Central Nervous System (CNS)

Brain and spinal cord.

Peripheral Nervous System (PNS)

Nerves outside the CNS, including 12 pairs of cranial nerves and 31 pairs of spinal nerves.

Sensory (Afferent) Division

Carries information from sense organs toward the brain and spinal cord.

Motor (Efferent) Division

Carries commands away from the brain and spinal cord to muscles and organs.

Autonomic Nervous System

Involuntary division controlling glands, cardiac muscle, and smooth muscle.

Sympathetic Nervous System

Autonomic division that speeds up body activity.

Parasympathetic Nervous System

Autonomic division that slows body activity.

Somatic Motor Division

Controls voluntary skeletal muscle movement.

Neuron

Nerve cell that receives stimuli and transmits impulses.

Axon

Neuron extension that carries impulses away from the cell body.

Dendrites

Branched neuron extensions that carry impulses toward the cell body.

Myelin Sheath

Fatty covering around an axon that helps nerve signals travel.

White Matter

Nervous tissue made mainly of bundles of myelinated axons.

Gray Matter

Nervous tissue containing neuron cell bodies, dendrites, and synapses.

Synapse

Junction where a neuron communicates with another neuron, muscle, or gland.

Neurotransmitter

Chemical messenger crossing a synapse to stimulate or inhibit another cell; examples include dopamine and serotonin.

Cerebrum

Largest brain region; involved in thought, memory, sensory interpretation, and voluntary movement.

Frontal Lobe

Controls planning, problem solving, behavior, emotions, and voluntary movement.

Parietal Lobe

Receives and interprets sensory information, especially body sensations.

Temporal Lobe

Processes sensory experiences, language understanding, and emotions.

Occipital Lobe

Interprets visual images and written words.

Thalamus

Relays sensory impulses to appropriate areas of the cerebral cortex.

Hypothalamus

Regulates blood pressure, temperature, water, and electrolyte balance.

Brainstem

Relays nerve signals and controls vital cardiovascular and breathing activities.

Cerebellum

Coordinates muscle activity, posture, and balance.

Cerebrospinal Fluid (CSF)

Fluid in brain ventricles and around brain and spinal cord that cushions and protects them.

Meninges

Three protective membranes covering the brain and spinal cord.

Dementia

Decline in memory and thinking that interferes with everyday functioning; not a normal part of aging.

Alzheimer Disease

Most common dementia; memory and cognition decline with abnormal protein clumps and tangles in the brain.

Vascular Dementia

Dementia caused by reduced blood supply to the brain, often from blocked arteries or stroke.

Frontotemporal Dementia (FTD)

Degeneration of frontal and temporal lobes affecting behavior, judgment, and language.

Delirium

Sudden altered mental state with confusion and difficulty paying attention; often reversible.

Epilepsy

Disorder involving recurrent seizures from abnormal electrical discharges in the brain.

Focal Seizure

Seizure beginning in one localized area of the brain, with awareness retained or impaired.

Generalized Seizure

Seizure affecting both sides of the brain.

Absence Seizure

Brief nonmotor seizure that may look like daydreaming, often beginning in childhood.

Tonic-Clonic Seizure

Motor seizure involving loss of consciousness, stiffening, and jerking.

Status Epilepticus

Prolonged or repeated seizure activity that is a medical emergency; the slides describe seizures lasting over 30 minutes.

Stroke (Cerebrovascular Accident, CVA)

Interruption of blood supply or bleeding in the brain that deprives tissue of oxygen.

Ischemic Stroke

Stroke caused by a blocked brain blood vessel; may be treated with clot-busting medication such as tPA.

Hemorrhagic Stroke

Stroke caused by a burst blood vessel or aneurysm producing bleeding.

Facial droop, Arm weakness, Speech difficulty, Time to call 911

Stroke warning signs: FAST

Transient Ischemic Attack (TIA)

Temporary stroke-like symptoms from briefly interrupted brain blood flow; warning sign of possible future stroke.

Hemiplegia

Paralysis on one side of the body

Hemiparesis

Weakness on one side of the body

Parkinson Disease

Loss of dopamine-producing neurons causing tremors, rigidity, shuffling gait, and weak voice.

Huntington Disease

Inherited progressive disorder causing jerky involuntary movements, personality changes, and later dementia.

Encephalitis

Inflammation of brain tissue, usually caused by a virus.

Traumatic Brain Injury (TBI)

Brain injury caused by an external force, such as a fall or vehicle accident.

Concussion

A mild traumatic brain injury with altered function

Contusion

A bruise of brain tissue

Meningitis

Inflammation of the meninges, commonly caused by viral or bacterial infection.

Subdural Hematoma

Bleeding occurs beneath the dura, often from veins

Epidural Hematoma

Bleeding occurs between skull and dura, often from an artery.

Bell Palsy

Sudden weakness or paralysis of one side of the face involving cranial nerve VII.

Trigeminal Neuralgia

Severe facial pain caused by irritation or compression of cranial nerve V.

Demyelination

Destruction or damage of the myelin sheath around nerve fibers.

Multiple Sclerosis (MS)

Chronic immune-related demyelination of brain, spinal cord, and optic nerves causing symptoms such as weakness, tingling, and vision loss.

Amyotrophic Lateral Sclerosis (ALS)

Progressive deterioration of motor neurons leading to increasing muscle weakness.

Peripheral Neuropathy

Damage or dysfunction of peripheral nerves; mononeuropathy affects one nerve and polyneuropathy affects many.

Shingles (Herpes Zoster)

Reactivation of the chickenpox virus causing painful nerve and skin symptoms.

Hydrocephalus

Excess cerebrospinal fluid enlarging brain ventricles, sometimes requiring a shunt.

Spina Bifida

Neural tube defect in which vertebral arches fail to close during fetal development.

Spina Bifida Occulta

The small partial deformity of the vertebral arch, without protrusion

Spina Bifida Cystica

Meninges and spinal cord protruding through the absent vertebral arch and
appearing as a cyst

Meningocele

Protrusion of meninges only

Meningomyelocele

Protrusion of meninges and spinal cord

Lumbar Puncture (LP)

Spinal tap used to collect cerebrospinal fluid from the subarachnoid space.

Electroencephalography (EEG)

Records electrical activity of the brain, often to evaluate seizures.

Electromyography (EMG)

Records electrical activity of muscles to evaluate muscle or nerve disorders.

Cerebral Angiography

Contrast imaging of brain blood vessels to find blockages or bleeding.

Positron Emission Tomography (PET)

Uses radioactive tracers, often attached to glucose, to evaluate brain function.

Craniotomy vs. Cranioplasty

Opening the skull for brain surgery VS repairing a skull defect.

Carotid Endarterectomy

Surgery to remove plaque from a carotid artery.

Psychology

Studies behavior and mental processes

Psychosis

Loss of contact with reality, which may involve hallucinations or delusions.

Schizophrenia

Mental disorder involving impaired perception of reality, disorganized thinking or speech, and sometimes hallucinations or delusions.

Hallucination

Perception without an external stimulus

Major Depression (Unipolar Disorder)

Persistent sadness or hopelessness for at least two weeks, often with loss of interest.

Bipolar Disorder

Mood disorder with episodes of depression and periods of mania or excessive excitement.

Seasonal Affective Disorder (SAD)

Depression occurring in a seasonal pattern, commonly in fall and winter.

Generalized Anxiety Disorder (GAD)

Excessive, difficult-to-control anxiety about multiple matters lasting more than six months.

Posttraumatic Stress Disorder (PTSD)

Symptoms after trauma such as flashbacks, nightmares, emotional numbness, and intense reactions to reminders.

Panic Disorder

Recurrent sudden attacks of intense fear with physical symptoms that peak rapidly.

Phobia

Intense fear of a specific object or situation

Obsessive-Compulsive Disorder (OCD)

Disorder involving unwanted recurring thoughts (obsessions) and/or repeated actions (compulsions).

Borderline Personality Disorder (BPD)

Personality disorder with unstable emotions, relationships, self-image, and impulsivity.

Narcissistic Personality Disorder

Exaggerated self-importance, need for attention or admiration, and lack of empathy.

Antisocial Personality Disorder

Persistent disregard for others' rights, often with deceitfulness and little remorse.

Dissociative Identity Disorder (DID)

Disorder involving two or more distinct identity states, often associated with trauma.

Kleptomania

Urges to steal

DSM-5

Diagnostic and Statistical Manual of Mental Disorders used in psychological evaluation and diagnosis.

Psychotherapy

Treatment of mental disorders using structured psychological approaches and conversation.

Cognitive Therapy

Therapy that changes unhelpful thought patterns

Phototherapy

Bright-light treatment often used for seasonal affective disorder.