Ch. 4 -The Nervous System and Mental Health

Amnesia

Loss of memory

Ataxia

Loss of muscular coordination

Axon

A fiber in the neuron that carries impulses away from the body of a cell.

Bradykinesia

Abnormal or slowness of motion

Central nervous system

The brain and spinal cord

Cephalgia (cephalalgia)

Headache

Cerebrospinal

Pertaining to the brain and spinal cord.

Craniotomy

Surgical opening into the skull.

Dendrite

A fiber in the neuron the carries impulses toward the body of a cell.

Discectomy

Surgical excision of an intervertebral disc.

Dysphasia

Impairment of speech (syn. aphasia)

Encephalomalacia

Softening of the brain often due to ischemia or infarction.

Epidural

Pertaining to above or outside the dura mater.

Epilepsy

A brain disorder characterized by electrical like disturbances resulting in seizures

Gray matter

Axons not covered in myelin

Hemiparesis

Weakness on one side of the body

Intracranial

Within the skull

Intrathecal administration

Injection into the spinal canal or subarachnoid space.

Laminectomy

Excision of the vertebral posterior arch or spinal process.

Meningitis

Inflammation of the meninges or the membranes covering the spinal cord or brain.

Myelin

A substance that covers some axons to insulate, protect, and assist in electrical conduction.

Myelitis

Inflammation of the spinal cord.

Neuralgia

Severe or stabbing pain the course or distribution of a nerve

Ischemia

Medical condition characterized by a restricted or reduced blood supply to any tissue, organ, or muscle group.

Infarction

Localized death of a tissue (necrosis) caused by prolonged lack of oxygen and nutrient delivery. Typically occurs when a blood vessel supplying the tissue is suddenly blocked by a clot, plaque or external compression.

Neuritis

Inflammation of a nerve

Neurologist

Physician who specializes in diagnosis and treatment of disorders of the nervous system.

Neurolysis

Destruction of nerve tissue or lysis (breaking up) perineural adhesions.

Neuron

Basic functional unit of the nervous system

Neurorraphy

Repair of severed nerve by suture, graft, or synthetic conduit.

Neurosis

Emotional condition or disorder; anxiety is a primary characteristic.

Neurotransmitters

A chemical that transmits energy across a synapse

Paranoia

A mental disorder often includes delusion involving perscution.

Peripheral nervous system

Nervous system outside the brain and spinal cord. 2 subcategories: somatic nervous system and autonomic nervous sytem

Poliomyelitis

Inflammation of gray matter of the spinal cord

Psychosis

An abnormal condition of the mind, gross disorganization, or distortion of mental capacity.

Quadriplegia

Paralysis of all 4 extremities

Radiculitis

Inflammation of the spinal nerve roots.

Sciatica

Severe pain along the sciatic nerve, usually unilateral based on the nerve root affected.

Subdural

Below the dura mater

Vagotomy

Surgical Incision of the vagus nerve

White matter

Axons that are covered in myelin.

Somatic Nervous System

Responsible for voluntary bodily movements.

Autonomic Nervous System

Controls involuntary responses. Ex, heart beating and intestines squeezing during digestive process.

Soma

Nerve cell body

Neuron

A single nerve cell. Comprised of a soma, containing the cell nucleus, several dendrites, and an axon.

Dendrites

Resemble tree branches and increase the number of possible connections among nerve cells

Axon terminals

Also called synaptic bulbs, do not touch the dendrites of a receiving neuron, separated by a synapse.

Synapse

The space between the axon terminals and dendrites. Across, minute electrical impulses are passed from one nerve to another via neurotransmitters.

Cerebrum

Located in the supratentorial region, contains the frontal, temporal, parietal and occipital lobe.

Frontal lobe

Part of the front of the brain and is involved in planning, organizing, problem solving, selective attention, personality, and a variety of higher cognitive functions including behavior and emotions. Part of the cerebrum

Temporal Lobes

2 on either side of the brain. The right lobe involves visual memory, and the left involves verbal memory. Help sort new information and are believed to be responsible for short term memory. Also evaluate hearing input and smell. Part of the cerebrum.

Parietal Lobe

Lie behind the frontal lobe and above the temporal lobe at the top of the brain. Contain primary sensory cortex controlling sensation. Right lobe processes visuospatial information and the left lobe processes spoken and written information.

Occipital Lobe

Back of the brain and processes visual information, including visual recognition of shapes and colors.

Cerebellum

Located in the infratentorial region at the bottom of the brain, below the occipital lobe. Helps coordinate movement.

Brainstem

Low extension of the brain where it connects to the spinal cord. Origin point for most cranial nerves. This region controls neurological functions necessary for survival (breathing, digestion, heart rate, blood pressure) and for arousal (being awake and alert). Pons and medulla are located here.

Ventricles of the brain

Structures containing cerebrospinal fluid (CSF). Continuous with the central canal of the spinal cord.

Cerebrospinal Fluid (CSF)

Bathes and cushions the brain and spinal cord.

Medulla oblongata

base of the brain

Conus medullaris

Space between first and second lumbar vertebrae.

Spinal Cord

Bundle of nerves that extend from the medulla oblongata down to the conus medullaris. Lies within the vertebral column, which protects it. Has 3 main functions: Serve a conduit for motor information traveling down to muscles, serve as a conduit for sensory information traveling up to the brain, and serve as the a center for coordinating reflexes.

Cauda Equina

Collection of nerves at the end of the spinal cord. Consists of the 2nd through 5th lumbar nerves, 5 sacra nerves and the coccygeal nerve.

7 Cervical Segements

Forms 8 pairs of cervical nerves.

12 thoracic segements

Form 12 pairs of thoracic nerves

5 Lumbar segements

Form 5 pairs of lumbar nerves

5 sacral segements

Form 5 pairs of sacral nerves (some anatomy texts consider this to be a single segement)

Coccyx

3-5 coccygeal vertebral segments fuse. 1 pair of coccygeal nerves.

Vertebral Segement

The basic constituent part into which the spine may be divided. Represents a single complete vertebral bone with its associate articular process and laminae.

Vertebral Interspace

The non-bony compartment between 2 adjacent vertebral bodies containing the intervertebral disc.

Corpus

Main portion of the vertebra

Vertebral Foramen

The passageway of the vertebral segements through which the spinal cord passes.

Spinous Process

The posterior projection of the vertebra.

Transverse Process

The projections on either side of the vertebrae

Laminae

Small ridged areas midway between the spinous process, transverse process and the vertebral arch.

Laminectomy

Complete excision of laminae in addition to the entire posterior portion of the vertebra (spinous process)

Laminotomy

Partial excision of one or more lamina for instance for nerve decompression.

Facet Joints

Also called paravertebral facet joints and zygapophyseal or z joints, are located on the posterior spine on each side of the vertebrae where it overlaps the neighboring vertebrae. Provide stability and give the spine the ability to bend and twist. Made up of 2 surfaces of the adjacent vertebrae that are separated by a thin layer of cartilage. Often the site of diagnostic or therapeutic injection

Myelin Sheath

A layer of fatty cells (Schwann cells) acting as insulation coating the axon. If not present, nerve impulses passing along an axon could generate unwanted responses in nearby neurons, resulting in jerky movement.

Nodes of Ranvier

Gaps in the myelin sheath

Schwann Cells

A layer of fatty cells in the myelin sheath.

Nerve Plexus

A network of intersecting nerves that combine spinal nerves serving the same body area.

Cervical Plexus

Serves head, neck and shoulders

Brachial Plexus

Serves the chest, shoulders, arms and hands.

Lumbar Plexus

Serves the back, abdomen, groin, thighs, knees and calves.

Sacral Plexus

Serves the pelvis, buttocks, genitals, thighs, calves and feet.

Solar (Celiac Plexus)

Serves internal organs

Femoral Nerve

Sensory (afferent) and motor (efferent) nerve supplying the front of the thigh and part of the lower leg.

Common Fibular Nerve (Common Peroneal)

Sensory and motor nerve supplying the knee and superior tibiofibular joints and tibialis anterior muscle. It divides into superficial and deep fibular (peroneal) nerves; a branch of the sciatic nerve supplying movement and sensation to the lower leg, foot and toes.

Intercostal Nerves

The upper thoracic nerves innervate primarily the chest and upper abdomen; only never not originating from a plexus.

Median Nerve

Innervates most flexor muscles of the forearm and provides sensation for the thumb, index, middle fingers, an a portion of the ring finger. It is the only nerve passing through the carpal tunnel.

Musculocutaneous Nerve

Sensory and motor nerve of the coracobrachialis, biceps, brachii, and the greater part of the brachialis (bicep and side of forearm). It arises from the brachial plexus.

Radial Nerve

Innervates the triceps brachii muscle of the arm and all 12 muscles in the posterior osteofascial compartment of the forearm.

Saphenous Nerve

Sensory nerve of the knee joint, subsartorial and patellar plexuses and the skin on the medial side of the leg and foot.

Sciatic Nerve

The largest nerve of the body, derived from spinal nerves L4 through S3, runs through the buttock and down the lower limb. It supplies the skin of the leg and muscles of the back and thigh. Divides just above the knee into the tibial and common fibular (common peroneal) nerves.

Subcostal Nerves

Sensory and motor nerves of the skin of lower abdomen and lateral side of gluteal region and parts of abdominal transverse, oblique and rectus muscles.

Tibial Nerve

Sensory and motor nerve supplies the muscles and skin of the knee, calf, sole of the foot, and toes; a branch of the sciatic nerve.

Ulnar Nerve

Provides sensation for the little finger and a portion of the ring finger and innervates some muscles of the hand and forearm.

ALS (Amyotrophic lateral sclerosis)

A progressive neurodegenerative disease that affects motor nerve cells in the brain (upper motor neurons) and spinal cord (lower motor neurons) causing loss of motor control. Most common degenerative disease of the neuromuscular system. Also known as lou gehrig’s disease.

Cerebrovascular Accident (CVA)

Occurs when the tissue in the brain is deprived of oxygen due to an interruption or reduction in the blood supply to the brain. Aka stroke

Ischemic Stroke

Caused by an abrupt blockage of arteries that supply oxygen rich blood to the brain. 87% of strokes