Summary
The vertebrate central nervous system contains the brain and the spinal cord, which are covered and protected by three meninges. The brain contains structurally and functionally defined regions. In mammals, these include the cortex (which can be broken down into four primary functional lobes: frontal, temporal, occipital, and parietal), basal ganglia, thalamus, hypothalamus, limbic system, cerebellum, and brainstem—although structures in some of these designations overlap. While functions may be primarily localized to one structure in the brain, most complex functions, like language and sleep, involve neurons in multiple brain regions. The spinal cord is the information superhighway that connects the brain with the rest of the body through its connections with peripheral nerves. It transmits sensory and motor input and also controls motor reflexes.
Glossary
amygdala
structure within the limbic system that processes fear
arachnoid mater
spiderweb-like middle layer of the meninges that cover the central nervous system
basal ganglia
interconnected collections of cells in the brain that are involved in movement and motivation; also known as basal nuclei
basal nuclei
see basal ganglia
brainstem
portion of the brain that connects with the spinal cord; controls basic nervous system functions like breathing, heart rate, and swallowing
cerebellum
brain structure involved in posture, motor coordination, and learning new motor actions
cerebral cortex
outermost sheet of brain tissue; involved in many higher-order functions
choroid plexus
spongy tissue within ventricles that produces cerebrospinal fluid
cingulate gyrus
helps regulate emotions and pain; thought to directly drive the body’s conscious response to unpleasant experiences
corpus callosum
thick fiber bundle that connects the cerebral hemispheres
cerebrospinal fluid (CSF)
clear liquid that surrounds the brain and spinal cord and fills the ventricles and central canal; acts as a shock absorber and circulates material throughout the brain and spinal cord.
dura mater
tough outermost layer that covers the central nervous system
frontal lobe
part of the cerebral cortex that contains the motor cortex and areas involved in planning, attention, and language
gyrus
(plural: gyri) ridged protrusions in the cortex
hippocampus
brain structure in the temporal lobe involved in processing memories
hypothalamus
brain structure that controls hormone release and body homeostasis
limbic system
connected brain areas that process emotion and motivation
meninge
membrane that covers and protects the central nervous system
occipital lobe
part of the cerebral cortex that contains visual cortex and processes visual stimuli
parietal lobe
part of the cerebral cortex involved in processing touch and the sense of the body in space
pia mater
thin membrane layer directly covering the brain and spinal cord
proprioception
sense about how parts of the body are oriented in space
somatosensation
sense of touch
spinal cord
thick fiber bundle that connects the brain with peripheral nerves; transmits sensory and motor information; contains neurons that control motor reflexes
sulcus
(plural: sulci) indents or “valleys” in the cortex
temporal lobe
part of the cerebral cortex that processes auditory input; parts of the temporal lobe are involved in speech, memory, and emotion processing
thalamus
brain area that relays sensory information to the cortex
ventricle
cavity within brain that contains cerebrospinal fluid