Central Nervous System ( Brain/ Spinal Cord Pathways) Flashcards
What is the function of the somatosensory tract (ascending)?
-Carries general sensory information
What is the function of the corticospinal tract (descending)?
-carries motor info from the brain to the spinal cord
Where is the location of the primary somatosensory area of the cerebral cortex?
-postcentral gyrus of the parietal lobe
Where is the location of the corticospinal tract(primary motor area)?
-precentral gyrus
The brain stem is divided into what structures (3)?
- midbrain
- pons
- medulla
Describe the structures and functions (white vs grey matter) of the Medulla
- transition from the spinal cord into the brains proper
- White Matter:includes somatosensory and corticospinal tracts(90% of Corticospinal tracts cross the midline to the opposite side of the body in the pyramids of the medulla)
- Olive:sensory relay station
- Gray matter: cardiovascular center, respiratory center
What is the functions of the pons?
- relay station for info transfer between the cerebellum and cerebrum
- contains sensory tract to thalamus
- respiratory center
What is the function of the midbrain (mesencephalon)
- controls eye movement
- integrates auditory info
- contains sensory and motor tracts
Where is the location of the diencephalon?
-lies between the brain stem and the cerebrum
What are the structures that make up the diencephalon(2)?
-Thalamus and hypothalamus
What is the function of the thalamus?
- sensory relay station (processes and relays sensory info to appropriate cortices
- Regulates the level of awareness
- composed of nuclei
What is the function of the hypothalamus?
- center of homeostasis
- activates sympathetic nervous system
- maintains body temp
- controls body osmolarity
- controls reproductive functions
- controls food intake
- interacts with limbic system to influence behavior and emotions
- influences cardiovascular control center in medulla oblongata
- circadium rhythm
What is the function of the cerebellum?
-processes sensory info and coordinate the execution of precise movement
(Voluntary;skeletal muscles)
The cerebrum is the site of what major function?
-higher brain function
What connects the two hemispheres of the cerebrum?
- corpus callosum (axons passing one side of the brain to the other)
- ensures that the two hemispheres communicate and cooperate
What are the structures of the gray matter of the cerebrum?
- cerebral cortex (outer later of the cerebrum)
- cerebral nuclei/ basal ganglia
What is the function of the cerebral cortex?
-higher brain functions arise here
What is the function of the cerebral nuclei/basal ganglia?
-subconscious control of the skeletal muscle movement
What is the function of the white matter(lipids form the myelin sheath) of the cerebrum?
-bundles of fibers that allow different regions of the cortex to communicate with one another and transfer info from one hemisphere to the other; primarily through the corpus callosum
What are the different lobes of the cerebrum?
1) frontal lobe
2) temporal lobe
3) parietal lobe
4) occipital lobe
5) insula
What does the frontal lobe of the cerebrum control?
- primary motor cortex, motor association area; skeletal muscle movement
- prefrontal association area
- coordinates info from other association areas, controls some behaviors
What does the parietal lobe of the cerebrum control?
- primary somatic sensory cortex, sensory association area
- sensory info from the skin, musculoskeletal system, viscera, and taste buds
What does the occipital lobe of the cerebrum control?
- visual cortex, visual association area
- vision
What does the temporal lobe of the cerebrum control?
- auditory cortex, auditory association area
- hearing
What does the insula of the cerebrum control?
- Gustatory cortex;taste
- olfactory cortex;smell (doesn’t go to thalamus)
Describe the cerebral lateralization of the cerebrum
- functional specialization is not symmetrical across the cerebral cortex
- each lobe has special functions not shared by the matching lobe on the other side
- “left - right brain dominance
What does the left hemisphere of the cerebrum specialize in (functions)?
- Speech and Language
- writing
- general interpretive center (language and mathematical calculation)
What does the right hemisphere of the cerebrum specialize in (functions)?
- cognitive function
- analysis by touch
- spatial visualization and analysis
How is sleep traced and measured? (Patterns)
-EGG (electroencephalography)
What are the characteristics of sleep?
- non-REM
- REM (rapid eye movement)=paradoxical sleep
What are the characteristics of REM sleep?
- vivid dream state
- increased metabolism
- major muscle groups paralyzed
What are different brain waves and their descriptions?
- Beta: Awake, excited, eyes open
- Alpha: Awake, relaxed, eyes closed
- Theta: sleep, deep relaxation
Delta: Deep sleep, dreamless
Describe the cycle/stages of sleep
- 90 minute cycles throughout the night
- Stage 1: Alpha
- Stage 2: Theta (light)
- Stage 3: Theta (deeper)
- Stage 4: Delta
- Stage 5: Beta (REM stage/high brain activity)
List some parasomias (disorders)
- insomnia
- sleep walking (occurs in stages 3,4)
- night terror (occurs in stages 3,4)
- sleep apnea
What is memory? It can be divided into what two types?
- ability to retain and recall info
- Short term and long term memory
What is short term memory?
-disappears unless an effort is made to make it permanent
What is long term memory? What are the 2 types?
- memories that are stored and retrievable
- Reflexive (implicit) memory, Declarative (explicit) memory
Describe reflexive (implicit) memory
- recall is automatic, no conscious effort
- acquired slowly through repetition
- procedural memories can be demonstrated
Describe Declarative (explicit) memory
- Recall requires conscious attention
- memories can be reported verbally
- depends of higher level thinking skills
Language is divided into 2 parts in the left temporal lobe, what are their names?
-Wernickes Area and Brocas Area
What is the function of Wernickes Area?
- Comprehension of vocal, written, and signed language (receptive)
- stores info for arranging learned vocab into meaningful speech
What is the function of Brocas Area(expressive)?
- speech production and articulation (motor skills)
- stores info needed for speech production (syntax)
- programs motor cortex to move tongue, lips, speech muscles
What is Aphasia?
-speech and language disorders
What are the types of Aphasia? (3)
- Receptive Aphasia
- Expressive Aphasia
- Mechanical Aphasia
Where does damage occur in Receptive Aphasia and what are the effects?
- damage to Wernickes area
- unable to recognize language in written/spoken form > produces meaningless speech
Where does damage occur in Expressive Aphasia and what are the effects?
- damage to Broca’s area
- loss of ability to produce spoken/written language
Where does damage occur in mechanical aphasia, and what are the effects?
- damage to motor cortex
- mechanical speech is disrupted
