UNIT 3: CNS BASIC ORGANIZATION
• Brain mass
• Ventricular system (Cerebrospinal
fluid)
• Cerebral hemispheres
• Lobes • Fissures
• Sulci & Convolutions (gyri)
• Cortex
• Basal Ganglia
• Limbic system
• Brainstem
• White matter pathways
• Vascular system
- Gyri and Sulci are the folds and indentations that give the brain its wrinkled
appearance.
- Gyri (or gyrus) are the folds or bumps in the brain
- Sulci (or sulcus) are the indentations or grooves.
●Medial longitudinal fissure: The sulcus that divides the brain
into two hemispheres
●Corpus callosum: Connects both hemispheres of the brain
●Sagittal plane: Divides the brain into left and right parts
●Horizontal/Axial plane: Divides the brain into superior (upper)
and inferior (lower) sections
●Frontal/Coronal plane: Divides the brain into an anterior (front)
and posterior (back) sections
Anterior means toward the nose end
Posterior means toward the tail end
Dorsal means toward the surface of the back or the top of the
head
Ventral means toward the surface of the chest or the bottom of
the head
Medial means toward the midline of the body
Lateral means toward away from the midline toward the body´s
lateral surface
Occipital: analysis of visual input to guide our behaviour.
Parietal:
- Postcentral gyrus: analyses sensations from the base
(ex: touch)
- Posterior parts play roles in perceiving the location of both
objects and our own body, and in directing our attention.
Temporal:
- Superior temporal gyrus (hearing and language)
- Middle temporal gyrus (certain kinds of memory)
- Inferior temporal gyrus (identifies complex visual patterns)
Frontal:
- Precentral gyrus: motor function
- Anterior parts to the precentral gyrus: complex cognitive
functions (planning response sequences…)
Cerebellum: sensorimotor structure
- Damage in cerebellum→eliminates the ability to precisely
control movement and to adapt to changing conditions.
- Also important in other cognitive functions (language).
• ROLANDO= postcentral gyrus
