Brain Anatomy and Functional Areas

Vocabulary practice flashcards covering gross anatomy of the brain, cranial meninges and CSF, major cerebral regions and lobes, cortical functional areas, sensory and motor homunculi, and lateralization.

William James

The early 20th-century psychologist who wrote in The Energies of Men that "we are making use of only a small part of our possible mental and physical resources," which was later popularized into the $10\%$ brain use myth.

Cerebrospinal Fluid (CSF)

The clear fluid circulating through brain ventricles, the subarachnoid space, and the central canal of the spinal cord that suspends and cushions the brain inside the skull.

Gyri

The elevated ridges or outward folds on the outer surface of the cerebral cortex.

Sulci

The shallow grooves or depressions located between the gyri of the cerebral cortex.

Fissure

A deep groove or deep sulcus located on the cerebral cortex, such as the longitudinal fissure.

Superior

An anatomical directional term meaning above or toward the top of a structure.

Anterior

An anatomical directional term indicating toward the front of the body or brain.

Posterior

An anatomical directional term indicating toward the back of the body or brain.

Central Sulcus

The sulcus that separates the frontal lobe from the parietal lobe and demarcates the precentral gyrus from the postcentral gyrus.

Lateral Sulcus

The prominent groove that separates the temporal lobe inferiorly from the frontal and parietal lobes superiorly.

Longitudinal Fissure

The deep sagittal cleft that divides the cerebrum into the left and right cerebral hemispheres.

Cerebrum

The largest of the four major regions of the brain, composed of five lobes and divided into two hemispheres.

Diencephalon

One of the four major regions of the brain, consisting of the epithalamus, thalamus, and hypothalamus.

Brainstem

A major region of the brain that connects to the spinal cord, composed of the midbrain, pons, and medulla oblongata.

Cerebellum

One of the four major regions of the brain, located posterior to the brainstem and inferior to the occipital lobe.

Gray Matter

Brain tissue composed primarily of neuronal cell bodies and dendrites, forming the cerebral cortex and deep cerebral nuclei.

White Matter

Brain tissue composed primarily of myelinated axons responsible for transmitting electrical impulses.

White Matter Tracts

Large bundles of myelinated axons in the central nervous system that span longer distances to connect different brain regions.

Cerebral Cortex

The outer superficial layer of the cerebrum, composed primarily of gray matter.

Cerebral Medulla

The inner region of the cerebrum underlying the cerebral cortex, composed of white matter.

Cerebral Nuclei

Deep clusters or islands of gray matter embedded within the white matter of the cerebral medulla.

Corpus Callosum

The large horizontal white matter tract connecting the left and right cerebral hemispheres.

Cerebral Lateralization

The functional specialization of each cerebral hemisphere for certain distinct cognitive, motor, or sensory tasks.

Categorical Hemisphere

The hemisphere—typically the left—specialized for sequential reasoning, language, verbal communication, and sciences.

Representational Hemisphere

The hemisphere—typically the right—specialized for artistic skill, music, visual-spatial relationships, and imagination.

Frontal Lobe

The anterior cerebral lobe responsible for decision making, concentration, planning, personality, verbal communication, and voluntary motor output.

Primary Motor Cortex

A functional motor region located within the precentral gyrus of the frontal lobe that controls voluntary skeletal muscle movement.

Motor Speech Area

A specialized motor region located in the frontal lobe responsible for coordinating the muscle movements needed for speech.

Parietal Lobe

The cerebral lobe located posterior to the central sulcus, primarily involved in receiving, integrating, and interpreting somatic sensory input.

Primary Somatosensory Cortex

The sensory region located within the postcentral gyrus of the parietal lobe that receives sensory inputs from the skin (touch, pressure, pain, temperature) and proprioceptors (joints, muscles).

Somatosensory Association Area

A functional area in the parietal lobe that integrates, interprets, and gives meaning to sensory information received from the skin, joints, and muscles.

Temporal Lobe

The cerebral lobe situated inferior to the lateral sulcus, involved in processing hearing, smell, and some vision, as well as storing auditory and visual memories.

Primary Auditory Cortex

The functional sensory region located within the temporal lobe responsible for processing hearing.

Primary Olfactory Cortex

The functional sensory region located in the temporal lobe responsible for processing smell.

Occipital Lobe

The most posterior cerebral lobe, responsible for processing visual inputs and coordinating eye movements.

Primary Visual Cortex

The functional cortical region located in the occipital lobe that receives and processes initial visual stimuli.

Visual Association Area

A functional region in the occipital lobe that integrates and interprets visual information to enable visual recognition.

Insular Lobe (Insula)

The fifth lobe of the cerebrum, located deep to the lateral sulcus and temporal lobe, involved in processing taste, smell, hearing, and inputs from visceral organs.

Primary Gustatory Cortex

A sensory area located within the insular lobe that is responsible for taste perception.

Upper Motor Neuron (UMN)

The first neuron in a descending motor pathway, having its cell body in the cerebral cortex and extending its axon to synapse in the spinal cord.

Lower Motor Neuron (LMN)

The second neuron in a descending two-neuron motor pathway, having its cell body in the spinal cord and sending its axon to innervate skeletal muscle.

Motor Homunculus

A somatotopic map depicting the anatomical arrangement and relative cortical representation of body structures across the primary motor cortex.

Sensory Homunculus

A somatotopic map depicting the distribution and relative cortical representation of body sensory reception along the primary somatosensory cortex.