Brain - Function

Brain

3.2 - 3.5 lbs of nervous tissue divided into three regions

Forebrain

Houses the cerebrum and diencephalon

Midbrain

Houses the middle of the brainstem

Hindbrain

Pons and medulla oblongata of brain stem and cerebellum

Cerebrum

The largest brain region divided into two hemispheres by the sagittal (longitudinal) fissure,

and separated from the cerebellum by the transverse fissure

Gyri

Elevated ridges on the cerebrum

Sulci

Shallow grooves on the cerebrum

Lobes

Each hemisphere is divided into these, mostly named for their overlying bones

Frontal

Lobe responsible for control of skeletal muscles

Parietal

Lobe responsible for sensory reception from skin and muscles

Temporal

Lobe responsible for auditory and olfactory (smell) integration

Occipital

Lobe responsible for visual integration

Insula

Lobe responsible for taste integration

Cerebral Cortex

The outer layer of the cerebrum composed of grey matter and is the location of our conscious mind

Cerebral White Matter

Inner layer of cerebrum that functions as lines of communication

Corpus Callosum

White matter allowing communication between the hemispheres

Diencephalon

The small, central part of the forebrain including the paired gray matter structures called the thalamus, hypothalamus, and epithalamus

Thalamus

Egg-shaped group of nuclei (clusters of gray matter in the CNS) where sensory impulses synapse and are directed to the appropriate areas of the cerebral cortex

Hypothalamus

Region of nuclei below the thalamus that regulate the body’s homeostasis including hunger, thirst, water balance, hormone levels, and body temperature

Pituitary Gland

Part of the the endocrine system that hangs from the hypothalamus via a stalk called the infundibulum

Epithalamus

Posterior to thalamus and dominated by the pineal gland which secretes melatonin to regulate the sleep-wake cycle

Brain Stem

The stalk-like region below the diencephalon consisting of white matter, which links the brain to the spinal cord, as well as deeper gray matter nuclei

Midbrain

Most superior region of brainstem possessing paired nuclei that protrude posteriorly

Superior Colliculus

Coordinates head and eye movements

Inferior Colliculus

Regulates the startle reflex

Pons

The anterior bulge of the brainstem that helps regulate breathing rhythm

Medulla Oblongata

Its nuclei form the autonomic reflex center, regulating heart rate and breathing rate; the most inferior part of the brain stem which is continuous with the spinal cord

Cerebellum

The second largest brain region performing the timing and coordination of body movements; composed of outer gray matter and inner white matter; divided into two hemispheres

Arbor Vitae

“Tree of Life”; the name given to the branching pattern of the white matter