Lab 2 - Bolded Terms

Cerebrum

largest part of the brain

• located at the top and front of the head

• responsible for conscious thought, movement, and sensory processing

Diencephalon

deep region of the brain located at the core of the cerebrum

• primary relay and processing center for sensory information and autonomic functions

• contains the thalamus, hypothalamus, epithalamus, and subthalamus

Midbrain

topmost part of the brainstem

• acts as a vital connection point between the forebrain (cerebrum and diencephalon) and the rest of the CNS

• Key functions: visual reflexes, auditory processing, motor control, pain modulation

Pons

middle section of the brainstem, located between the midbrain and the medulla oblongata

• key functions: signal relay, breathing regulation, sleep and dreaming, autonomic functions

Medulla Oblongata

the lowest part of the brainstem, connecting the pons to the spinal cord

• controls automatic life-support functions

• key functions: cardiovascular control, respiratory control, reflex centers, nerve decussation

Cerebellum

highly folded structure located at the back of the brain

• primarily responsible for coordinating movement, balance, and posture

Choroid Plexus

specialized blood vessels and ependymal cells that produce CSF

• located within the ventricles of the brain

• Key functions: CSF Production, Blood-CSF Barrier, Waste Clearance, Nutrient Transport

Lateral Ventricles

two largest cavities in the brain’s ventricular system

• located deep within the cerebral hemispheres

• responsible for producing, storing, and circulating CSF

• each lead into an inter-ventricular foramen, which opens to the third ventricle

Septum Pellucidum

thin membrane that separates the lateral ventricles

Interventricular Foramen

a pair of narrow channels located at the midline of the brain, responsible for connecting each lateral ventricle to the third ventricle

• CSF drainage, pressure regulation, fluid circulation

Third Ventricle

found within the right and left halves diencephalon (thalamus and hypothalamus)

• narrows inferiorly to form the cerebral aqueduct

• CSF transport, brain protection, endocrine communication

Cerebral Aqueduct

a narrow, fluid-filled channel located within the midbrain that connects the third ventricle to the fourth ventricle

• CSF conduit, hydrodynamic balance, structural protection

Fourth Ventricle

large, diamond-shaped expansion located within the brainstem

• as it narrows inferiorly, it joins the central canal of the medulla and spinal cord

• CSF distribution, mechanical cushioning, chemical sensing

Dura Mater

most superficial of the meninges

• fibrous membrane provides a resilient layer around the brain

Arachnoid Mater

on the innermost surface of the dura

• fine strands extend across the subarachnoid space to the deepest meninx, the pia mater

Pia Mater

deepest meninx

Subarachnoid Mater

filled with CSF

• provides a watery cushion surrounding the brain

Dural Venous Sinuses

the dura mater’s two sub-layers divide to form these

• these passages function as veins, draining blood away from the brain and scalp

Arachnoid Granulations

out-pockets of the arachnoid mater

• penetrate the dural venous sinuses surrounding the brain

• excess CSF returns to the blood through these specialized regions

Commissural Tracts

connect the right and left sides of the brain

• type of white matter of axons

Projection Tracts

connect higher and lower regions of the central nervous system

• may be ascending or descending, depending on the direction of information flow

• can be found in the interneurons of the corticospinal and spinothalamic pathways described within the spinal cord module

Association Tracts

generally found in the cerebrum, these tracts connect one part of the cortex to adjacent regions of the same hemisphere

Frontal Lobe

the largest of the four major lobes of the brain, located at the very front of the cerebral cortex, directly behind the forehead

• functions: executive functioning, voluntary movement, speech production, personality and behavior

Parietal Lobe

one of the four major lobes of the cerebral cortex, located near the upper back of the skull, directly behind the frontal lobe and above the occipital love

• Function: somatosensory processing, spatial awareness, sensory integration, language and math

Occipital Lobe

smallest of the four major lobes of the cerebral cortex

• located at the very back of the skull, sitting directly behind the parietal and temporal lobes

• Functions: visual perception, shape and color recognition, spatial processing, visual memory

Temporal Lobe

one of the four major lobes of the cerebral cortex

• located on the lower sides of the brain, roughly level with your eyes and directly beneath the frontal and parietal lobes

• Functions: auditory processing, language comprehension, memory formation, visual and emotional recognition

Insular Lobe

hidden region of the cerebral cortex located deep within the lateral sulcus, completely covered by the overlying flaps of the frontal, parietal, and temporal lobes

• serves as a vital bridge linking sensory experiences, emotional processing, and internal bodily awareness

• Functions: monitors internal bodily states, gustatory processing, emotional awareness, autonomic control, pain processing

Longitudinal Fissure

separates the right and left hemispheres

• a major groove

Central Sulcus

a groove that divides the frontal and parietal lobes

Lateral Sulcus

a groove that divides the temporal from frontal and parietal lobes

Parieto-Occipital Sulcus

a groove that divides the parietal and occipital lobes

Precentral Gyrus

a prominent ridge located on the posterior surface of the frontal lobe, positioned directly in front of the central sulcus

• serves as the brain’s main control center for executing voluntary physical movements

Primary Motor Cortex

functional region of the cerebral cortex located within the precentral gyrus of the frontal lobe

• brain’s principal command center for initiating and executing voluntary muscle movements across the opposite side of the body

• Functions: movement execution, force and direction, precise kinematics

Postcentral Gyrus

prominent ridge located on the anterior surface of the parietal lobe, positioned directly behind the central sulcus

• houses the primary somatosensory cortex and serves as the brain’s main processing center for body sensations

Primary Somatosensory Cortex

located on the postcentral gyrus of the parietal lobes

• serves as the brain’s principle processing center for raw sensory inputs arriving from across the opposite side of the body

• Functions: tactile discrimination, sensation localization, thermal and pain perception, proprioception

Primary Visual Cortex

the main cortical region responsible for receiving and processing raw visual information

• located at the very back of the brain within the occipital lobe

• Functions: initial visual processing, feature extraction, ocular dominance

Primary Auditory Cortex

the principal cortical region responsible for processing sound

• located on the upper surface of the temporal love

• Functions: sound perception, basic feature extraction, sound localization

Primary Olfactory Cortex

the principal cortical region responsible for receiving and processing smell information

• uniquely positioned because it receives direct sensory inputs from the olfactory bulb without first routing through the thalamus

Primary Gustatory Cortex

principal brain region responsible for the conscious perception and discrimination of taste

Prefrontal Cortex

integrate inputs from multiple senses allowing us to make meaning of the information we receive

• known to be important in social interactions and personality

Basal Nuclei

aka basal ganglia

• cluster of interconnected, deep-seated masses of gray matter located within the white matter of the cerebral hemispheres

• responsible for modulating motor movement, habit formation, and reward loops

Internal Capsule

massive, compact bundle of white matter fibers (axons) located deep within each cerebral hemisphere

• carriers almost all the ascending sensory signals from the body up to the cerebral cortex and descending motor signals from the cortex down to the brainstem and spinal cord

Amygdala

involved in memory, decision-making, and emotional responses

• primary radar for detecting threats and processing emotions

• Functions: fear and threat detection, emotional conditioning, memory consolidation, social and behavioral processing

Hippocampus

involved in spatial memory and navigation

• major, seahorse-shaped structure located deep within the temporal lobe of each cerebral hemisphere

• Functions: memory consolidation, spatial navigation, contextual learning, neurogenesis

Corpus Callosum

massive bundle of white matter contains axons that are responsible for communication between cerebral hemispheres

• Functions: interhemispheric communication, sensory integration, task coordination

Pineal Gland

one of the primary structures of the diencephalon

• produces melatonin, which prepares the brain for sleep

Thalamus

one of the primary structures of the diencephalon

• has two egg-shaped halves with the third ventricle sandwiched between them

• often called the relay station of the brain because it is the synapse site for nearly all sensory pathways

Hypothalamus

one of the primary structures of the diencephalon; below the thalamus

• has several nuclei containing autonomic control centers, body temperature control, sleep cycle control centers, and emotional control centers

• responds to stimuli in the brain by releasing hormones that control the pituitary gland

Pituitary Gland

a structure found suspended from the hypothalamus

• produces hormones that control the thyroid, adrenal cortex, liver, and reproductive function

Cerebral Peduncles

large bundles that contain projection tracts

• allow communication between the cerebral hemispheres and lower parts of the CNS

• part of midbrain

Corpora Quadrigemina

part of the midbrain

• four rounded elevations located on the posterior surface of the midbrain

  • four bodies arranged in two pairs (superior and inferior colliculi)

  • Functions: visual tracking, auditory startle reflex, sensory integration

Superior Colliculi

nuclei on the posterior side of the midbrain that initiate visual reflexes, such as the coordination of eye and head movements when tracking a moving object

• part of the midbrain, specifically the corpora quadrigemina

Inferior Colliculi

nuclei on the posterior midbrain that receive auditory information and coordinate reflexive actions in response to sounds

• part of the midbrain, specifically corpora quadrigemina

Cerebellar Peduncles

part of the pons

• three large, paired bundles of white matter nerve fibers that connect the cerebellum to the brainstem

• communication pathways allowing the cerebellum to receive sensory inputs and fine-tune motor outputs

• Functions: Motor feedback loop, balance maintenance, precision tuning

Medullary Pyramids

large ridges on the anterior surface of the medulla oblongata

• contain descending corticospinal tracts which contain axons directing voluntary movements of the body

Arbor Vitae

Vermis

Limbic System

Reticular Formation

Olfactory Nerves (CN1)

Olfactory Bulbs

Olfactory Tracts

Optic Nerves (CN2)

Optic Chiasm

Optic Tracts

Vestibulocochlear Nerves (CN8)

Oculomotor Nerves (CN3)

Trochlear Nerves (CN4)

Abducens Nerves (CN6)

Trigeminal Nerve (CN5)

Facial Nerve (CN7)

Glossopharyngeal Nerve (CN9)

Vagus Nerve (CN10)

Spinal Accessory Nerve (CN11)

Hypoglossal Nerve (CN12)