Chapter 14: Central Nervous System - The Brain

Vocabulary flashcards covering the anatomical structures, functional divisions, protective barriers, and pathways of the brain and central nervous system from Chapter 14 lecture notes.

Gyri

Thick folds on the surface of the brain that increase surface area.

Sulci

Valleys or shallow grooves located between the folds of the brain.

Fissure

Deep grooves located on the surface of the brain.

Nucleus (CNS)

A group of neuron cell bodies located within the central nervous system (composed of gray matter).

Tract

A bundle of axons located within the central nervous system (composed of white matter).

Meninges

Three connective tissue membranes located between the brain and skull that provide protection and create a framework for blood vessels.

Dura Mater

The tough outermost connective tissue layer of the cranial meninges.

Arachnoid Mater

The spider-like middle meninx; beneath it lies the subarachnoid space filled with cerebrospinal fluid ($\text{CSF}$).

Pia Mater

The soft, delicate innermost meninx lying closest to the surface of the brain.

Gray Matter

Nervous tissue consisting of neuron cell bodies and dendrites; forms the outer rim (cerebral cortex, accounting for $40\%$ of brain mass) and deep basal nuclei.

White Matter

Nervous tissue composed of myelinated tracts and axons; appears white due to the fat content in myelin.

Choroid Plexus

Capillary networks lined with ependymal cells located in the brain ventricles that produce cerebrospinal fluid ($\text{CSF}$).

Cerebrospinal Fluid (CSF)

A clear, colorless fluid produced at $500\,\text{ml/day}$ that resembles extracellular fluid but lacks protein; fills the ventricles and canals and coats the surface in the subarachnoid space.

Blood-Brain Barrier

A protective barrier formed by tight junctions between capillary cells and assisted by astrocytes to regulate the movement of substances into brain tissue.

Blood-CSF Barrier

A protective barrier located at the choroid plexus formed by tight junctions between ependymal cells.

Stroke

The sudden death of brain tissue caused by a loss of blood flow.

Parietal Lobe

Cerebral lobe responsible for processing general senses, taste, and spatial perception.

Occipital Lobe

Cerebral lobe dedicated to visual processing.

Temporal Lobe

Cerebral lobe responsible for hearing, smell, learning, memory, and language.

Frontal Lobe

Cerebral lobe responsible for voluntary motor control, memory, behavior, personality, and conscious abstract thought.

Association Area

Cortical region where received sensory input is interpreted and processed.

Motor Association Area

Cortical region where the intent to move is formulated.

Primary Motor Cortex

Cortical region responsible for controlling voluntary motor activity by sending signals to move.

Wernicke Area

Brain area specialized for the recognition of spoken and written language.

Broca Area

Brain area that generates the motor program required to produce speech.

Prefrontal Cortex

Anterior frontal lobe region responsible for mood, motivation, planning, personality, and judgment.

Primary Somatosensory Cortex

Cortical area specialized for processing general senses.

Postcentral Gyrus

A cerebral gyrus located posterior to the central sulcus that receives general sensory information.

Sensory Homunculus

A cortical map of sensory input where the proportional size of a body region reflects its processing power and sensitivity.

Motor Homunculus

A cortical map where the size of each represented body region corresponds to the degree of fine motor control it possesses.

Contralateral

Receiving sensory information from or controlling motor functions on the opposite side of the body.

Ipsilateral

Relating to, originating on, or acting on the same side of the body.

Categorical Hemisphere

The left cerebral hemisphere, specialized for analytical reasoning, science, and math.

Representational Hemisphere

The right cerebral hemisphere, specialized for imagination, music/art, patterns, and spatial relationships.

Basal Nuclei

Deep cerebral gray matter structures involved in motor control, repetitive movements (such as walking), and learned behaviors (such as writing and driving).

Association Tracts

Nerve fiber bundles confined to the same hemisphere that link perception with memory and other senses (finding meaning).

Projection Tracts

Vertical nerve fiber tracts that connect the cerebrum with the brainstem and spinal cord.

Commissural Tracts

Nerve fiber tracts that connect the two cerebral hemispheres to each other, such as the corpus callosum.

Thalamus

A diencephalic relay station and gateway to the cerebral cortex that receives sensory information and relays motor messages within the brain.

Hypothalamus

The master control center for the autonomic nervous system ($\text{ANS}$) and endocrine system; regulates homeostasis including temperature, thirst, hunger, reproduction, metabolism, and growth.

Epithalamus (Pineal Gland)

A diencephalic structure that secretes melatonin and plays a role in regulating the circadian rhythm.

Amygdala

A limbic system structure responsible for fear, anxiety, and strong emotions.

Hippocampus

A limbic system structure critical for memory formation and consolidation.

Cerebellum

Brain structure accounting for $10\%$ of brain mass and $50\%$ of all neurons, featuring extensive gyri and sulci; coordinates motor control, balance, and posture.

Arbor Vitae

The branching white matter of the cerebellum, known as the "tree of life."

Superior Colliculus

Midbrain structure responsible for visual reflexes and tracking.

Inferior Colliculus

Midbrain structure responsible for hearing and auditory reflexes.

Pons

A brainstem structure serving as a bridge between nervous pathways, involved in sleep and respiration.

Medulla Oblongata

Inferior brainstem structure containing the cardiac center ($\text{HR}$), vasomotor center ($\text{BP}$), respiratory centers (rate and depth), and reflex centers for chewing, swallowing, coughing, sneezing, and vomiting.

Cranial Nerves

Components of the peripheral nervous system ($\text{PNS}$) that connect the brain directly to the head and face.