Sympathetic and Parasympathetic Nervous System Overview

Sympathetic division

"Fight or flight", Prepares the body to deal with emergencies, Increases alertness, metabolic rate, and muscular abilities.

Heightened mental alertness

Increased awareness and focus during stressful situations.

Increased metabolic rate

The rate at which the body converts food into energy is elevated.

Reduced digestive and urinary functions

Decreased activity in the digestive and urinary systems during stress.

Activation of energy reserves

Mobilization of stored energy for immediate use.

Increased respiratory rate

The rate of breathing is elevated to supply more oxygen.

Dilation of respiratory passageways

Widening of airways to facilitate increased airflow.

Increased heart rate and blood pressure

Elevated heart rate and blood pressure to enhance blood flow.

Activation of sweat glands

Stimulation of sweat production to cool the body.

Dilation of pupils

Enlargement of pupils to enhance vision.

Increased blood flow to skeletal muscles

Enhanced circulation to muscles for improved performance.

Release of adrenaline (epinephrine) and norepinephrine (NE)

Hormonal response that prepares the body for action.

Decreased metabolic rate

Reduction in the rate of energy expenditure.

Decreased heart rate and blood pressure

Lowered heart rate and blood pressure during relaxation.

Increased secretion by salivary and digestive glands

Enhanced production of saliva and digestive fluids.

Increased motility and blood flow in digestive tract

Enhanced movement and circulation within the digestive system.

Stimulation of urination and defecation

Increased urge to urinate and defecate.

Parasympathetic division

"Rest and digest", Conserves energy and maintains resting metabolic rate.

Constriction of pupils

Narrowing of pupils to reduce light entry.

Secretion by digestive glands

Production of digestive fluids to aid in digestion.

Absorption and use of nutrients by peripheral cells

Utilization of nutrients by cells outside the digestive system.

Changes associated with sexual arousal

Physiological responses linked to sexual excitement.

Increased smooth muscle activity (peristalsis) in digestive tract

Enhanced contractions that move food through the digestive system.

Stimulation and coordination of defecation

Facilitation of bowel movements.

Contraction of urinary bladder during urination

Tightening of bladder muscles to expel urine.

Constriction of respiratory passageways

Narrowing of airways during relaxation.

Reduction in heart rate and force of contraction

Decreased heart activity during rest.

Dual innervation

Refers to an organ or tissue that receives input from both branches of the autonomic nervous system.

Autonomic tone

The baseline level of activity in the autonomic nervous system, reflecting the balance between sympathetic and parasympathetic input.

Autonomic plexuses

Nerve networks that are comprised of sympathetic and parasympathetic nerves that reach the same targets.

Memory consolidation

The process by which short-term memories are strengthened and converted into long-term memories, making them more stable and lasting over time.

Short-term memories

Memories that can be recalled immediately, do not last long, and contain small bits of information.

Long-term memories

Memories that include secondary memories, which fade with time and require effort to recall, and tertiary memories, which do not fade.

Amygdaloid body and hippocampus

Components of the limbic system that are essential to memory consolidation.

Nucleus basalis

Cerebral nucleus near the diencephalon that plays an uncertain role in memory storage and retrieval.

Cerebral cortex

Stores most long-term memories and refers conscious motor and sensory memories to appropriate association areas.

REM sleep

A stage of sleep associated with dreaming, characterized by active dreaming, changes in blood pressure and respiratory rate, and intense inhibition of somatic motor neurons.

Abdominopelvic quadrants

Divisions of the abdominopelvic cavity into Right Upper quadrant, Left Upper quadrant, Lower Left quadrant, and Lower Right quadrant.

Abdominopelvic regions

Divisions of the abdominopelvic cavity into Right/Left Hypochondriac Region, Right/Left Lumbar Region, Right/Left Iliac Region, Epigastric region, Umbilical region, and Hypogastric region.

Anatomical position

The body standing upright, facing forward, arms at the sides, and palms facing forward.

Prone

Refers to lying face down.

Supine

Refers to lying face up.

Proximal

Closer to the origin of the body part or the point of attachment of a limb to the body trunk.

Visceral

Pertaining to the covering of an organ.

Contralateral

On the opposite side of the body.

Superior (cranial)

Above, toward the head or upper part of the body.

Inferior (caudal)

Below, away from the head or toward the lower part of the body.

Anterior (ventral)

Toward or at the front of the body; in front of.

Posterior (dorsal)

Toward or at the back of the body; behind.

Medial

Toward or at the midline of the body; on the inner side of.

Lateral

Away from the midline of the body; on the outer side of.

Intermediate

Between a more medial and a more lateral structure.

Distal

Farther from the origin of a body part or the point of attachment of a limb to the body trunk.

Superficial (external)

Closer to or on the surface.

Deep (internal)

Farther from the surface.

Parietal

Pertaining to the wall of a body cavity.

Ipsilateral

On the same side of the body.

Cephalic

Head

Acromial

Shoulder

Cervical

Neck

Olecranal

Back of elbow

Lumbar

Loin (lower back)

Gluteal

Buttock

Popliteal

Back of knee

Sural

Calf

Calcaneal

Heel of foot

Plantar

Sole of foot

Cranial

Skull

Facial

Face

Nasal

Nose

Ocular/Orbital

Eye

Otic

Ear

Buccal

Cheek

Oral

Mouth

Mental

Chin

Axillary

Armpit

Brachial

Arm

Antecubital

Front of elbow

Antebrachial

Forearm

Carpal

Wrist

Palmar

Palm

Pollex

Thumb

Digits

Fingers

Thoracic

Chest

Mammary

Breast

Abdominal

Abdomen

Umbilical

Navel, belly button

Pelvic

Pelvis

Manual

Hand

Inguinal

Groin

Pubic

Pubis

Femoral

Thigh region

Patellar

Knee cap

Crural

Leg (shin)

Tarsal

Ankle

Digital

Toes

Hallux

Big toe

Pedal

Foot

Frontal

Forehead

Parietal Serosa

Thin membrane that lines the walls of body cavities and provides a protective lining and reduces friction between organs and the cavity walls.