Brain Anatomy & Functional Landmarks

Vocabulary flashcards covering major anatomical landmarks, functional areas, fiber tracts, and clinical terms discussed in the lecture on brain anatomy and physiology.

Central Sulcus

Major groove that separates the frontal lobe from the parietal lobe; motor cortex lies anterior to it, sensory cortex posterior.

Frontal Lobe

Anterior cerebral lobe responsible for motor functions, speech production, planning and reasoning.

Parietal Lobe

Cerebral lobe posterior to the central sulcus; houses the primary somatosensory cortex.

Primary Motor Cortex

Strip of cortex immediately anterior to the central sulcus that initiates voluntary movement; located in the frontal lobe.

Primary Somatosensory Cortex

Strip of cortex immediately posterior to the central sulcus that processes touch, pain, temperature and proprioception; located in the parietal lobe.

Lateral Fissure

Deep groove that separates the temporal lobe from the frontal and parietal lobes; anything below it is temporal lobe.

Temporal Lobe

Inferior-lateral cerebral lobe containing the hearing (auditory) cortex and Wernicke’s area.

Occipital Lobe

Posterior cerebral lobe devoted primarily to vision; lies behind the parieto-occipital sulcus and lateral fissure termination.

Broca’s Area

Left frontal-lobe region that controls the motor aspects of speech production.

Wernicke’s Area

Left temporal-lobe region that enables comprehension and formulation of meaningful language.

Longitudinal Fissure

Mid-sagittal groove that divides the brain into right and left hemispheres.

Parieto-Occipital Sulcus

Groove that separates the parietal lobe from the occipital lobe.

Sulcus (plural: Sulci)

A groove or furrow on the brain surface that increases cortical surface area.

Commissural Fibers

White-matter tracts (e.g., corpus callosum) that connect corresponding areas of the two hemispheres.

Corpus Callosum

Largest commissural fiber bundle allowing communication between right and left cerebral hemispheres.

Association Fibers

White-matter tracts connecting different regions within the same cerebral hemisphere.

Projection Fibers

Tracts that link the cerebral cortex with lower brain centers and spinal cord, often relaying through the thalamus.

Thalamus

Major relay station that channels all ascending sensory and descending motor signals; origin of projection fibers.

Basal Nuclei

Group of deep cerebral nuclei (e.g., caudate nucleus, substantia nigra) involved in motor control and associated disease states.

Caudate Nucleus

Basal-nuclei component implicated in Huntington’s chorea and motor regulation.

Substantia Nigra

Dopamine-producing basal nucleus whose degeneration contributes to Parkinson’s disease.

Amygdaloid Nuclei

Basal nuclei associated with emotion; degeneration linked to Alzheimer’s disease.

Homunculus

Cortical map depicting body regions served by specific areas of the sensory or motor cortex.

Reticular Activating System (RAS)

Network spanning brainstem, thalamus and cortex that regulates wakefulness and consciousness.

Ascending Tracts

Spinal pathways that carry sensory information upward to the brain.

Descending Tracts

Spinal pathways that transmit motor commands from the brain to the body.

Dorsal (Posterior) Spinal Root

Sensory pathway entry point to the spinal cord; always carries afferent signals.

Ventral (Anterior) Spinal Root

Motor pathway exit point from the spinal cord; always carries efferent signals.

Aphasia

General term for impairment of language ability due to brain injury.

Broca’s Aphasia

Non-fluent, slurred or “broken” speech production with relatively preserved comprehension.

Wernicke’s Aphasia

Fluent but nonsensical or jumbled speech resulting from impaired language comprehension.

Auditory (Hearing) Cortex

Portion of the temporal lobe that processes sound information.