structure of brain - phys

identify structures of the brain

cerebral cortex

• covers the cerebrum, which is part of the forebrain

• divided into 4 lobes: frontal, parietal, occipital, temporal

• 3mm thick, gray matter

• integrating center: connects and processes input and controls skeletal muscle movement

cerebrum

• part of forebrain

• divided into left and right hemispheres, connected by corpus callosum

• surrounded by cerebral cortex

thalamus

• in the diencephalon (forebrain)

• serves as a synaptic relay point

• integrates incoming information

• plays a key role in general arousal, focusing attention (filter out extraneous info)

hypothalamus

• in the diencephalon (forebrain)

• lies below the thalamus and above the pituitary gland

• functions: homeostatic regulation, preservation of the individual (eat/drink) and species (reproduction)

epithalamus

• part of diencephalon (forebrain)

• small mass of tissue that includes the pineal gland

• pineal gland helps control circadian rhythms by releasing melatonin

• connection between limbic system and rest of brain

limbic system (components and functions)

• components: thalamus, hypothalamus, part of frontal and temporal lobe cortexes, hippocampus and connections to other parts of CNS

• gray matter

• function: Learning, Emotional experience and behavior, Endocrine and Visceral functions

cerebellum

• part of hind brain

• coordinates movements and controls posture and balance (does not initiate movement)

• receives info from muscles, joints, skin, eyes, ears, viscera, other parts of brain involved in control of movement

  • mostly motor functions but also implicated in some forms of learning

brainstem

• made of midbrain, pons, and medulla oblongata

• all nerve fibers between spinal cord and brain pass through here

• reticular formation (in brainstem): receives and integrates info from all region of CNS

  • involved in motor functions, cardiovascular and respiratory control, regulation of sleep, consciousness, focus of attention

part of spinal cord associated with sympathetic NS

T1-L2 vertebrae

part of spinal cord associated with parasympathetic NS

• cranial nerves 3, 7, 9, 10

• sacral vertebrae

where is CSF secreted?

by ependymal cells in the choroid plexuses of the ventricles of the brain

flow of CSF

• from ependymal cells → throughout brain and spinal cord → valves in the top of the brain → large veins via venous sinuses (becomes a part of venous blood)

• completely replaced ~3x per day