Cns Brain Flashcards
Central nervous system
Brain
Spinal cord
3 main parts
Cerebrum
Cerebellum
Brain stem
Meninges
Brain is wrapped in 3 layers of connective tissue
Meninges
Inner most layers
Covers PIA matter
Fibrous layer which carry food and oxygen to the brain
Outer layer called dura matter
Arachnoid between PIA and dura material
Between PIA and arachnoid is CSF
Foramina
Blood vessels and nerves enter the brain through holes in the skull
Blood Brian barrier
Protects brain from foreign substances
Protects the brian from hormones and neurotransmitters
Maintains homeostasis
Circle of Willis
Provides a safety mechanism if one of the arteries gets blocked the circle will still provide brain with blood
Circumventricular organs
Areas of the brain where BBB is weak and allows substances to cross into the brain freely
Pineal body
Neurohypophysis
Area postrema
Pineal body
Secretes melatonin and neuroactive peptides associated with circadian rhythms
Neurohypiphysis
Releases neurohormones like oxytocin and vasopressin (ADH) into the blood
Area postrema
Vomiting center
When a toxic substance enters blood stream it will get to the area postrema and may cause vomiting
BBB can be broken down by
Hypertension
Lack of congenital development
Hyperosmolaity
Radiation
Infection
Trauma ischemia inflammation pressure
Cerebrum
Only structure of the telencephalon
Largest portion of brain (80% mass)
Responsible for higher mental functions
-corpus callosum: interconnects left and right hemisphere
Cerebrum function
Control center of the brain
Largest and most prominent part of the human brain
Responsible for all voluntary activities
Site of intelligence learning and judgment
Functions in language conscious thought memory personality development and vision
Left right hemisphere
Linked by A tract
Tract tells what other gave is doing
Numerous folds
Right hemisphere
Creativity and artistic ability
Left hemisphere
Analytical and mathematic ability
Frontal lobe
Anterior portion of each cerebral hemisphere
Body regions with the greatest number of motor innervation are represented by largest areas of motor cortex
Parietal lobe
Primary area responsible for perception of somatesthetic sensation
Body regions with highest densities of receptors are represented by largest areas of sensory cortex
Temporal lobe
Contain auditory centers that receive sensory fibers for cochlea
Interpretation and association of auditory and visual information
Occipital lobe
Primary area responsible for vision and coordination of eye movements
Folded outer surface
Cerebral cortex consists of gray matter
Inner surface
Cerebral medulla Consists of white matter
Cerebellum
Second largest part of the brain located at the back of the skull
Cerebellum functions
Coordinates muscle movements balance posture and coordination
Receives sensory impulses from muscle tendons joints eyes and ears as well as input from brain centers
Brain stem
Connects the Brian to the spinal cord
Consist of diencephalon, medulla oblongata pons and midbrain
Maintains life support system
Medulla Contains white mater
Invoulantary functions breathing heart rate digestion
RAS system
Pons link between cerebral cortex and cerebellum
Midbrain: smallest divison of the lower brain stem
Thalamus
Composed of grey mater
Switching station for sensory input
Exception of smell
Passes information to the proper region of the cerebrum for further processing
Epithalamus
Choroid plexus where CSF is formed
Pineal gland recreated melatonin
Hypothalamus
Regulates sleep wake emotions sexual arousal anger fear pain
Stimulates hormonal release
Produces ADH and oxytocin
Sympathetic and parasympathetic reflexes
Posterior pituitary
Stores and realizes ADH and ozytocin
Anterior pituitary
Regulates secretion of hormones of other endocrine glands
Kim if system
Thalamus hypothalamus deeper parts of cerebral cortex and temporal lobes
Emotions memory motivation
