Class 5 Neuroanatomy

Central Nervous System (CNS)

Consists of the brain and spinal cord; integrates information and controls thought, emotion, memory, learning, and movement.

Peripheral Nervous System (PNS)

Transmits signals between the CNS and the rest of the body.

Cerebrum

Largest part of the brain responsible for higher cognitive functions including thinking, memory, learning, emotions, and impulse control.

Cerebellum

Coordinates voluntary movement, balance, posture, motor learning, eye movements, and speech coordination.

Brainstem

Composed of the midbrain, pons, and medulla; relays sensory and motor information and controls vital functions.

Midbrain

Upper portion of the brainstem involved in movement and sensory processing.

Pons

Middle portion of the brainstem involved in sleep, breathing, and communication between brain regions.

Medulla Oblongata

Lower portion of the brainstem controlling breathing, heart rate, and blood pressure.

Cerebral Cortex

Outer layer of the cerebrum responsible for higher cognitive processing.

Gyri

Ridges or folds of the cerebral cortex that increase surface area.

Sulci

Grooves between gyri that increase cortical surface area.

Neocortex

Evolutionarily newest part of the cerebral cortex consisting of six layers.

Cortical Layer I-III

Responsible primarily for cortico-cortical associative connections.

Cortical Layer IV

Main recipient of sensory input from the thalamus.

Cortical Layer V

Sends motor output to subcortical structures.

Cortical Layer VI

Sends information back to the thalamus and participates in higher cognitive functions.

Structural Asymmetry

Physical differences between the left and right cerebral hemispheres.

Functional Asymmetry

Specialization of cognitive functions between the two cerebral hemispheres.

Lateralization

Localizing specific cognitive functions predominantly to one hemisphere.

Wada Test

Procedure used to determine language and memory dominance by temporarily anesthetizing one hemisphere.

Corpus Callosum

Large bundle of nerve fibers connecting the left and right cerebral hemispheres.

Frontal Lobe

Responsible for executive functions, planning, decision-making, personality, voluntary movement, and language production.

Executive Functions

Higher-order cognitive processes including planning, inhibition, organization, and problem solving.

Broca's Area

Region of the left frontal lobe responsible for speech production and motor planning of language.

Broca's Aphasia

Expressive aphasia characterized by slow, effortful speech with relatively preserved comprehension.

Phineas Gage

Railroad worker whose frontal lobe injury demonstrated the role of the frontal lobe in personality and decision-making.

Parietal Lobe

Processes somatosensory information and contributes to spatial awareness.

Primary Somatosensory Cortex

Cortical region that processes touch, pain, temperature, pressure, and body position.

Two-Point Discrimination

Test of somatosensory cortical function measuring the ability to distinguish two nearby points of touch.

Spatial Awareness

Ability to understand the position of the body and objects in space.

Contralateral Neglect

Hemispatial neglect syndrome in which patients ignore one side of space, usually after right parietal damage.

Temporal Lobe

Processes hearing, language comprehension, memory, and emotion.

Primary Auditory Cortex

Receives and processes auditory information.

Wernicke's Area

Region responsible for understanding spoken and written language.

Wernicke's Aphasia

Receptive aphasia characterized by fluent but nonsensical speech with poor language comprehension.

Hippocampus

Brain structure essential for forming new long-term memories.

Amygdala

Brain structure involved in emotional processing, especially fear.

Occipital Lobe

Primary center for visual processing.

Primary Visual Cortex (V1)

Receives visual input from the eyes and performs initial visual processing.

Visual Recognition

Process of identifying and interpreting visual information.

Coronal (Frontal) Plane

Divides the body into anterior and posterior sections.

Sagittal Plane

Divides the body into left and right sections.

Transverse (Horizontal) Plane

Divides the body into superior and inferior sections.

Rostral

Direction toward the front (anterior) of the brain.

Caudal

Direction toward the back (posterior) of the brain.

Dorsal

Direction toward the top (superior) of the brain.

Ventral

Direction toward the bottom (inferior) of the brain.

Medial

Toward the midline of the brain.

Lateral

Away from the midline of the brain.

Language Lateralization

Localization of language functions primarily in the left hemisphere for most individuals.

Motor Learning

Process of acquiring and improving motor skills through practice.

Homeostasis

Regulation of vital bodily functions such as breathing, heart rate, and blood pressure by the brainstem.

Sensory Integration

Process of combining information from multiple sensory systems to understand the environment.