Human Brain and Nervous System Lecture Notes

Vocabulary flashcards based on lecture notes about the human brain and nervous system.

Transverse fissure

Separates the cerebrum from the cerebellum.

Parts of the human brain

The human brain is made up of the cerebral hemispheres, diencephalon, brain stem, and cerebellum.

Brain ventricles

Chambers filled with cerebrospinal fluid which is produced there.

Meninges

Three layers of connective tissue membranes that cover and protect central nervous system organs and enclose cerebrospinal fluid.

Dura mater

Double-layered outer meninx.

Arachnoid meninx

A loose layer separated from the dura mater by the subdural space.

Subarachnoid space

Contains blood vessels and is filled with cerebrospinal fluid.

Pia mater meninx

A thin connective tissue tightly attached to the brain.

Choroid plexus

Produces cerebrospinal fluid.

Blood-brain barrier

A diffusion barrier which prevents most particles from entering the central nervous system tissue, keeping the brain and spinal cord separate from general blood circulation.

Blood-brain barrier

Formed by the relatively impermeable brain capillaries, due to the glial cells astrocytes.

Cerebrum

The foremost part of the brain, is the largest part of the brain in humans comprising about 83% of total brain mass

Median longitudinal fissure

Separates the left and right cerebral hemispheres from one another.

Gyri

Raised ridges on the cerebrum.

Cerebral cortex

The outer portion of the cerebral hemispheres and is highly convoluted and gray in color.

Frontal lobe

Controls higher level executive functions such as reasoning and decision making, motor functions, and permits control over voluntary muscle actions.

Parietal lobe

Receives sensory information from receptors in the mouth for taste and located in the skin, such as those for touch, pressure, and pain.

Occipital lobe

Interprets visual input.

Temporal lobe

Has sensory areas for hearing and smelling.

Primary areas

Receive information for one type of sensory information.

Association areas

Act mainly to integrate more than one type of sensory information for purposeful action.

Brainstem

Made up of the midbrain, pons, and medulla oblongata.

Medulla oblongata

Regulates heartbeat and breathing.

Pons

Regulates head movements in response to visual and auditory stimuli.

Hypothalamus

Maintains homeostasis, the constancy of the internal environment and controls the pituitary gland and serving as a link between the nervous and endocrine systems

Pineal body

Secretes melatonin to control the wake-sleep cycle

Cerebellum

Below and at the back of the brain, is convoluted and divided into two hemispheres with deep fissures subdividing it into three lobes

Cerebellum function

Acts to coordinate body movements.

Intermediate lobe, vermis

Coordinates limb movements.

Limbic system

Connects the frontal lobes, the temporal lobes, the thalamus, and the hypothalamus.

Amygdala

A small portion of the limbic system that is involved in emotions such as rage and anger.

Limbic system

Stimulation of different areas of the limbic system causes rage, pain, pleasure, or sorrow, which is why it's called our "feeling brain".

Limbic system function related to memories

The involvement of the limbic system explains why emotionally charged events result in our most vivid memories.

Basal ganglia

The putamen, the caudate nucleus, the Globus pallidus (medial and lateral).

Spinal cord

Extends from the brain stem to the first lumbar vertebra where it officially terminates as the conus medullaris.

Extension of the cord beyond L1

A collection of nerve roots called the cauda equina which runs to its end at the coccyx.

Spinal Cord function

Is how all impulses travel between the brain and the rest of the body by way of the set of 31 pairs of spinal nerves.

Protections for the spinal cord

The bony vertebral column, meninges and cerebrospinal fluid.

Outer meninx of the spinal cord

A single layer called the spinal dural (mater) sheath, is separated from the vertebral column by a cushioning fat-filled epidural space.

Spinal cord meninges

The space between the middle arachnoid and inner pia mater meninges is filled with cerebrospinal fluid.

Spinal tap function

Removal of fluid for diagnostic testing.

Gray matter of the spinal cord

Composed of multipolar neurons and supporting cells.

White matter of the spinal cord

Composed of myelinated and unmyelinated nerve fibers.

White matter fibers of the spinal cord

Composed of ascending tracts that proceed up to the brain carrying sensory inputs and descending tracts that proceed down to (or within) the cord carrying motor outputs.

Visceral motor

When they control smooth muscles or involuntary functions.

Cranial nerves

Humans have twelve pairs most of which control the head, neck, and face.

Olfactory nerve

Sense of smell.

Optic nerve

Sense of sight.

Oculomotor nerve

Eye movement, pupil dilation.

Trochlear nerve

Eye movement.

Trigeminal nerve

Chewing and sensation of face, nose, and mouth.

Abducens nerve

Eye movement.

Facial nerve

Facial expressions and sensation of tongue. Lacrimal, nasal mucous glands.

Vestibulocochlear nerve

Hearing and balance.

Glossopharyngeal nerve

Swallowing and taste. Parotid salivary glands.

Vagus nerve

Digestion, regulation of heart rate, sensation of digestive tract.

Accessory nerve

Rotation of the head and movement of upper shoulders.

Hypoglossal nerve

Tongue movements.

Human spinal nerves

Eight pairs, twelve pairs, five pairs, five pairs, one pair.

Dorsal root

Contains the axons of afferent sensory neurons, which conduct impulses to the cord.

Ventral root

Contains the axons of efferent motor neurons, which conduct impulses away from the cord.

Dorsal ramus

The smaller, contains nerves that serve the dorsal portions of the trunk including the skin and muscles of the back.

Ventral ramus

The larger, contains nerves that serve the remaining ventral parts of the trunk and the upper and lower limbs.

Nerve plexus

A network of interconnecting spinal nerves carried together to some target location.

Dermatome

A region of skin that carries sensory information through a specific pair of spinal nerves to the spinal cord and up to the brain.

Phrenic nerve

Supplies both motor and sensory fibers to the diaphragm.

Five final nerves that come from the Brachial plexus

Axillary nerve, the radial nerve, the median nerve, the musculocutaneous nerve and the ulnar nerve.

Axillary nerve

Supplies the deltoid muscle, the teres minor muscles and the triceps brachii muscle.

Radial nerve

Supplies the triceps brachii muscle as well as 12 muscles in the forearm.

Median nerve

Supplies flexor muscles of the forearm and the skin of the first 3 ½ fingers.

Musculocutaneous nerve

Supplies the flexor muscles of the arm: biceps brachii and brachialis.

Ulnar nerve

Supplies part of the flexor muscles of the forearm, wrist, and hand as well as the skin of half the ring finger and pinky finger.

Femoral nerve

The major nerve of the Lumbar plexus.

Sciatic nerve

The major nerve that comes from the sacral plexus and is the largest nerve in the human body.

Femoral nerve

Supplies the hip flexors and knee extensors.

Sciatic nerve

Supplies the inferior trunk and posterior surface of the thigh.

Divisions of the autonomic nervous system

The sympathetic and parasympathetic systems.

The sympathetic nervous system functions during an emergency

Accelerates the heartbeat, dilates the bronchi, and increases the breathing rate supplying needed oxygen and causes the liver to deliver more glucose and inhibits the digestive tract.

Parasympathetic nervous system

Promotes all the internal responses we associate with a relaxed state.

Preganglionic axon

A motor neuron cell body located in the spinal cord or brain. The axon synapses with a second motor neuron located in an autonomic ganglion outside the spinal cord.

Sympathetic system being called the thoracolumbar division

Because this division contains preganglionic fibers from the thoracic and upper lumbar segments of the spinal cord, in the lateral gray horns.

Sympathetic trunk ganglia or lateral ganglia

Located on both sides of the spinal cord, these contain the ganglia for the sympathetic nervous system that controls the effector organs in the trunk, head and limbs.

Celiac ganglion

Largest of the ganglia, these ganglia innervate the digestive tract.

Superiomesenteric ganglion

Innervates the small intestine and parts of the large intestine.

Inferior mesenteric ganglion

Innervates the large intestine, kidneys, bladder and sex organs.

Ciliary ganglion

Associated with cranial nerve III, this targets the intrinsic eye muscles which change the pupil and lens.

Pterygopalatine ganglion & Submandibular ganglion

Associated with CN VII, the target organs are for tear production, nasal glands and salivary glands

Otic ganglion

Associated with CN IX, the target glands are the parotid glands.

Intramural ganglia

Associated with CN X, the target glands are the visceral organs within the thoracic cavity.

Major neurotransmitter in the parasympathetic system

Acetylcholine

Slight head injury

A slight injury of this type is called a concussion since the symptoms are mild and transient including dizziness or brief loss of consciousness.

Intracranial pressure

The amount of pressure available inside the skull.

Apraxia

Impaired motor planning resulting in rigid movements and difficulty executing a motor plan.

Ataxia

Impaired motor coordination, resulting from an injury to the cerebellum.

Ischemic and hemorrhagic

The types of strokes

Quadriplegia

Paralysis of all four limbs.

Median nerve

Compression results in carpal tunnel syndrome.

Ulnar nerve

Compression results in the ulnar claw sign.

Sciatica

Results from compression of the sciatic nerve.