Week 7 - Central Nervous System Flashcards
What are the brain regions?
- cerebral hemispheres (2 hemispheres)
- diencephalon
- brain stem
- cerebellum
Describe the cerebral hemispheres.
- they are paired (left and right)
- superior parts of the brain
- include more than half of the brain mass
- the surface is made of elevated ridges (gyri/gyrus) and grooves (sulci/sulcus)
- fissures are deeper grooves
- loves are named for the cranial bones that lie over them
What are the 3 main regions of the cerebral hemisphere?
- cortex is superficial gray matter
- white matter
- basal nuclei are deep pockets of gray matter
What is part of the cerebral hemispheres?
- cortex: gray matter
- basal nuclei
What is part of the Diencephalon region?
- thalamus
- hypothalamus
- limbic system — a functional system
What is part of the Cerebral hemispheres?
- midbrain
- pons
- medulla oblongata
- reticular fromation — a functional system
What is part of the Cerebellum?
- cerebellum
Function of Cortex: gray matter
- localizes and interprets sensory inputs
- controls voluntary and skilled skeletal muscle activity
- acts in intellectual and emotional processing
function of basal nulclei
- subcortical motor centers help control skeletal muscle movements (figure 7.14)
function of thalamus*
- relays sensory impulses to the cerebral cortex
- relays impulses between cerebral motor cortex and lower motor centers
- involved in memory
function of hypothalamus*
- **KEYWORD - REGULATION
- chief integration center of the autonomic (involuntary) nervous system
- regulates body temperature, food intake, water balance, and thirst
- regulates HORMONAL OUTPUT of anterior pituitary gland and acts as an endocrine organ (producing ADH and oxytocin)
function of limbic system — a functional system
- includes cerebral and diencephalon structures (e.g. hypothalamus and anterior thalamic nuclei)
- mediates emotional response; involved in memory processing
anatomy of midbrain
- contains visual and auditory reflex centers
- contains subcortical motor centers
- contains nuclei for cranial nerves III and IV
- contains projection fibers (e.g. fibers of the pyramidal tracts)
anatomy of pons
- relays information from the cerebrum to the cerebellum
- cooperates with the medullary centers to control respiratory rate and depth (breathing)
- contains nuclei of cranial nerves V-VII
- contains projection fibers
anatomy of medulla oblongata
- relays ascending sensory pathway impulses from skin and proprioceptors
- contains nuclei controlling heart rate, blood vessel diameter, respiratory rate, vomiting, etc.
- relays sensory information to the cerebellum
- contains nuclei of cranial nerves VIII-XII
- contains projection fibers
- site of crossover pyramids
- where the motor pathway crosses over
function of reticular formation — a functional system
- RAS
- maintains cerebral cortical alertness; filters our repetitive stimuli
- helps regulate skeletal and visceral muscle activity
function of cerebellum
- process information from the cerebral motor cortex, proprioceptors, and visual and equilibrium pathways
- provides “instructions” to the cerebral motor cortex and subcortical motor centers, resulting in smooth, coordinated skeletal muscle movements
- responsible for proper balance and posture
What is the primary somatic sensory area (cerebral cortex)?
- located in parietal lobe posterior to central sulcus
- receives impulses from the body’s sensory receptors
—– pain, temperature, light touch (except for special senses) - sensory homunculus is a spatial map
left side of the primary somatic sensory area receives impulses from right side (vice versa)
Cerebral areas involved in special senses
- visual area (occipital lobe)
- auditory area (temporal lobe)
- olfactory area (temporal lobe)
What is the primary motor area (cerebral cortex)?
- located anterior to the central sulcus in the frontal lobe
- allows us to consciously move skeletal muscles
- motor neurons form pyramidal (corticospinal) tract, which descends to spinal cord
- motor homunculus is a spatial map