Human Anatomy & Physiology I - The Brain and Spinal Cord

These flashcards cover key concepts related to human anatomy and physiology, specifically focusing on the brain, spinal cord, and associated structures.

Spinal Cord

The part of the central nervous system that extends from the brainstem to the lower back, composed of nerve tissues.

Cervical Enlargement

Regions of the spinal cord where spinal nerves serving the upper limbs emerge.

Cauda Equina

A collection of nerve roots at the inferior end of the vertebral canal.

Conus Medullaris

The terminal portion of the spinal cord that tapers to a point.

Filum Terminale

A fibrous extension of the pia mater that anchors the spinal cord to the coccyx.

Denticulate Ligaments

Delicate shelves of pia mater that attach the spinal cord to the vertebrae.

Gray Matter

Region of the spinal cord containing neuron cell bodies, unmyelinated axons, and neuroglia.

Gray Commissure

Connects the masses of gray matter in the spinal cord and encloses the central canal.

Posterior (Dorsal) Horns

Parts of the gray matter in the spinal cord that contain interneurons.

Anterior (Ventral) Horns

Parts of the gray matter that contain somatic motor neurons and interneurons.

Lateral Horns

Regions in the spinal cord that contain sympathetic nerve fibers.

Sensory Roots

Dorsal half of gray matter carrying sensory information to the spinal cord.

Motor Roots

Ventral half of gray matter carrying motor commands away from the spinal cord.

Spinal Nerves

31 pairs of mixed nerves that emerge from the spinal cord, serving various body regions.

Dermatome

A specific area of skin that receives sensory input from a pair of spinal nerves.

Cerebrospinal Fluid (CSF)

A clear fluid that surrounds the brain and spinal cord, providing buoyancy and protection.

Blood-Brain Barrier (BBB)

A selective barrier that protects the brain from harmful substances while allowing nutrients to pass.

Decussation

The crossing over of nerve fibers from one side of the body to the other.

Reflex Arc

The neural pathway that mediates a reflex action.

Afferent Fiber

Nerve fibers that carry sensory signals to the central nervous system.

Efferent Fiber

Nerve fibers that carry motor commands away from the central nervous system.

Polysynaptic Reflex

A reflex pathway that involves more than one synapse.

Monosynaptic Reflex

A reflex pathway that involves only one synapse.

Flexor Reflex

A reflex that involves the contraction of flexor muscles to withdraw a body part from a painful stimulus.

Corticospinal Tract

The pathway from the cerebral cortex to the spinal cord involved in voluntary movement control.

Lumbar Plexus

A network of nerves arising from the lumbar region of the spine that supplies the lower limbs.

Brachial Plexus

A network of nerves formed from the lower cervical and upper thoracic spinal nerves supplying the upper limb.

Cervical Plexus

A network of nerves formed from the upper cervical spinal nerves, primarily supplying the head and neck.

Sciatic Nerve

The largest nerve in the body, arising from the sacral plexus and supplying the lower limb.

Spinal Cord Transection

A complete cross-sectioning of the spinal cord which results in loss of function below the injury.

Spastic Paralysis

Condition in which the primary motor cortex is damaged, but spinal neurons remain intact.

Flaccid Paralysis

Condition resulting from damage to the lower motor neurons, leading to loss of muscle control.

Spinal Nerve Damage

Damage to spinal nerves can be assessed through testing dermatomes.

Choroid Plexus

A structure in the ventricles of the brain that produces cerebrospinal fluid.

Meninges

Three protective membranes covering the brain and spinal cord: dura mater, arachnoid mater, pia mater.

Hydrocephalus

A condition characterized by excessive accumulation of cerebrospinal fluid in the brain.

Traumatic Brain Injury (TBI)

An injury to the brain resulting from an external force.

Cerebral Edema

Swelling of the brain due to excess fluid accumulation.

Primary Motor Cortex

The area of the brain involved in planning and executing movement.

Primary Somatosensory Cortex

The region of the brain responsible for processing sensory information from the body.

Spinal Reflexes

Involuntary reactions to stimuli processed at the level of the spinal cord.

Arachnoid Mater

The middle layer of the meninges, which contains cerebrospinal fluid.

Pia Mater

The delicate inner layer of the meninges, tightly adhering to the brain.

Falx Cerebri

A fold of dura mater that separates the two cerebral hemispheres.

Tentorium Cerebelli

A dural fold that separates the cerebellum from the cerebrum.