Brain

Spinal Cord

It is the Control Center of N.S.

consists of nerves in brain & spinal cord

nerves that connect CNS with receptors, muscles, glands and sense organs

voluntary movement- efferent neurons

impulses from CNS to skeletal muscle (external)

involuntary visceral- efferent neurons

impulses from CNS to smooth, gland, cardiac muscle (internal)

Somatic afferent neurons

Visceral afferent neurons

Somatic efferent neurons

Visceral efferent neurons

cells that support and protect

smaller and numerous

tumors: “gliomas”

star-shaped, support & attach neurons to blood vessels

part of blood-brain barrier

small cells, protection

“brain macrophages”

multilayered, segmented, white, phospholipid covering CNS axons

“white matter”

helps conduct impulses (insulates axon)

“white matter” Schwann cells (Sheath of Schwann)

Nodes of Ranvier: gaps

Receptor

Sensory Neuron

Center

Motor Neuron

Effector ---> “Reflex” : Spinal / Somatic / Visceral

restored resting membrane potential

Na+ OUT / K+ IN

Membrane layers surrounding CNS

inflammation: “meningitis”

Cranial cavity – cranium (skull)

a. Dura mater- outer layer

b. Dura sinus- venous

c. Dura mater- inner layer

d. Subdural space- serous fluid

e. Arachnoid- middle layer, spider-like

f. Subarachnoid space- Cerebral spinal fluid (CSF) – lumbar puncture

g. Pia mater- inner, delicate layer closest to brain / contains blood vessels

h. BRAIN

Spinal Cavity- vertebra(e)

a. Epidural space- contains adipose tissue, C.T.,and vessels

b. Dura mater

c. Arachnoid

d. Subarachnoid space- CSF: lumbar puncture

e. Pia mater

f. SPINAL CORD

Brain Stem

Diencephalon

Cerebellum

Cerebrum

Medulla Oblongata

Pons

Midbrain

Thalamus

Hypothalamus

vital reflex center

cardiac, rhythmicity, vasomotor center

swallowing, vomiting, coughing, sneezing, hiccupping

cross-over: motor fibers from right cerebral cortex control left side of body

voluntary motor pathway between cord and brain

2 oval bodies

has most sensory & motor afferent neurons

sensations: pain, temp, touch, pressure (not olfactory)

below thalamus

connects cerebral cortex & lower autonomic center

link between cognitive mind and physiological body (ie. sound, smell, taste)

thirst center, body temp, appetite, waking/ sleeping, emotion- aggression, sex

links nervous system to endocrine system

Antidiuretic Hormone-ADH: affects excretion / fluid balance (decreasing urine production)

Oxytocin: uterine contraction (labor) & lactation

Releasing Factors: affects hormone release from the anterior pituitary gland

Second largest part of the brain

Responsible for:

Fine muscle movement

Subconscious skeletal muscle movement

Coordination

Damage: same side motor dysfunction

Posture, equilibrium, speech, gait

Test: touch nose with eyes closed

Largest part of brain

12 billion neurons

Interprets sensation, controls voluntary motor activities, intellect, reason, memory, language, consciousness

Cerebral cortex- outer, gray matter

Basal ganglia- inner, white matter

Gyri- convolutions

Sulci- shallow grooves

Fissures- deep grooves

located in the longitudinal fissure

cord tissue connecting right / left hemispheres

responsible for brain integration

right & left hemisphere communication

Frontal: motor of opposite side, speech

Parietal: sensory, smell, motor, taste

Occipital: visual

Temporal: auditory, smell

Sensory: receives and interprets sensory organ data

Motor: voluntary and some involuntary

Association: intellect, learning, recall-memory, language, reasoning

Limbic: a system, action or visceral

Emotions, autonomic, sexual, biological rhythms, pleasures, subconscious motor and sensory

left-handed

music, art, imagination, insight, images

right-handed

speech, writing, numbers, scientific, logic

Transmits impulses to and from brain

Located inside spinal cavity / vertebral canal

Internal: gray matter-cell bodies of motor and inter-neurons

External: white mater of myelinated axons and dendrites on interneurons

31 spinal nerve fibers in ascending and descending tracts

First & Second: 2 lateral ventricles

Third: between right & left halves of thalamus and between lateral ventricles

Fourth: inferior to brain stem and cerebellum

Communicates with subarachnoid space of brain and spinal cord

Chroid plexuses→

lateral ventricles→

inter-ventricular foramina→

third ventricle→

cerebral aqueduct→

fourth ventricle→

subarachnoid space (back of brain) →

posterior spinal cord→

anterior spinal cord→

posterior spinal cord→

anterior brain→

arachnoid villi for reabsorption

Acetylcholine

Dopamine

Serotonin

Gamma aminobutyric acid (GABA)

Encephalins

Endorphins

Epinephrine / Norepinephrine

CNS to visceral effectors

Unconscious control

Maintains internal homeostasis by integration Part of peripheral nervous system

ANS fibers release neurotransmitters at synapses and visceral effectors- neuroeffector junctions of muscles or glands

Regulated by cerebral cortex, hypothalamus, medulla oblongata

Oppose each other by excitation / inhibition

Sympathetic expends energy

Parasympathetic restores / conserves energy

Down’s syndrome (Mongolism)

Spina bifida

Anencephaly

Leukodystrophy (Krabbe’s Disease)

Mennigitis: bacterial – E. coli, Haemophilus influenza, Streptococcus pneumonia, Neisseria meningitidis / viral

Encephalitis: Herpes simplex I, Varicella zoster

Rabies

Myelitis: “Poliomyelitis” virus

Neuritis

Cerebral Vascular Accident: “stroke”

Concussion

Contusion

Epidural hematoma

Subdural hematoma

Penetrating injuries

Nerve Pressure

Multiple Sclerosis (MS)

Amyotrophic Lateral Sclerosis (ALS)

Senile dementia

Alzheimer’s parkinson’s

Hydrocephalus

Epilepsy

Brain neoplasms

Organic mental disorders- drugs, toxins, metabolites

Psychoses and Schizophrenia

Affective disorders- bipolar / unipolar

Anxiety disorders

Personality disorders

Psychophysiologic disorders

Hyperkalemia

Alkalosis

Acidosis

hyper- high; kalium, potassium; -emia, "in the blood"

refers to the condition in which the concentration of the electrolyte potassium (K+) in the blood is elevated. The symptoms of elevated potassium are nonspecific, and the condition is usually discovered on blood tests performed for another reason. Extreme hyperkalemia is a medical emergency due to the risk of potentially fatal abnormal heart rhythms (arrhythmia).