A&P Test 4 - Brain Flashcards
How is the cerebrum divided?
Into hemispheres
What does each cerebral hemisphere contain?
One large lateral ventricle
Where is the 3rd ventricle?
In the diencephalon.
What does the 3rd ventricle communicate with?
The lateral ventricles (in the cerebrum).
Where is the 4th ventricle?
In the medulla oblongata.
What does the 4th ventricle become?
It becomes continuous with the central canal of the spinal cord.
What connects with the 4th ventricle? How does it connect?
The 3rd ventricle, via a narrow canal called the aqueduct of midbrain.
How does the 4th ventricle connect?
With aqueduct of midbrain
Name 3 physical protections of the brain
bones of cranium, cranial meninges, CSF (cerebrospinal fluid)
Name 1 biochemical isolation of the brain
blood-brain barrier
Name the 3 layers of the cranial meninges:
dura mater, arachnoid mater, pia mater. These are continuous with the spinal meninges
What does the CSF do?
Cushions neural structures
Supports brain
Transports nutrients & waste products
What does the choroid plexus do?
It is specialized ependymal cells & capillaries that secrete CSF into ventricles, remove waste from CSF and adjust composition of CSF
Extensions in subarachoid space are …
Arachnoid villi
How is blood supplied to the brain?
Internal carotid arteries and vertebral arteries
How is blood removed from dural sinuses?
Internal jugular veins
Give an example of cerebrovascular disease
Stroke or cerebrovascular accident (CVA), which shuts off blood to portion of brain & neurons die
What kind of materials pass through the blood-brain barrier?
Lipophyllic materials
Name the important functions of the cerebrum
Controls all conscious thoughts & intellectual functions Processes somatic (voluntary) sensory and motor information
Name 3 functional principles of the cerebrum
Each hemisphere gets sensory info from, and sends motor commands to, the opposite side of the body
The 2 hemispheres have different functions although their structure look alike
Correspondence between a specific function & a specific region of the cortex is not precise
Where is gray matter in the cerebrum?
In cerebral cortex & basal nuclei
Where is white matter in the cerebrum?
Deep to basal cortex & around basal nuclei
What forms the lobes?
Sulci
What forms the hemispheres?
Fissures
What does the central sulcus divide?
The frontal lobe from the parietal lobe
What divides the frontal lobe form the temporal lobe?
Lateral sulcus
What divides the parietal lobes from the occipital lobe?
Parieto-occipital sulcus
Explain the function of each lobe of the cerebrum
Frontal: Primary motor cortex. Voluntary control of skeletal muscles
Parietal: primary sensory cortex. Conscious perception of touch, pressure, pain, vibration, temp, taste
Occipital: visual cortex. Perception of visual stimuli
All lobe association areas, integration & processing of sensory data
What does the left hemisphere control:
Reading, writing, math, decision making, speech and language
What does the right hemisphere control?
Senses (touch, smell, sight, taste, feel ) and recognition (faces, voice inflection)
How is brain activity assessed?
With an EEG – electroencephalogram
What are the 4 types of brain waves & what they mean?
Alpha: awake adults with eyes closed
Beta: adults concentrating or mentally stressed
Theta: children, intensely frustrated adults & in adults with mental disorders
Delta: sleep waves; also in adults with brain damage
A temporary cerebral disorder is a…
It cane measured with …
seizure…. EEG (eleectroencephalogram)
What are the 4 classifications of cranial nerves?
Sensory (touch, pressure, temp, pain), special sensory (sight, smell, hearing, balance), motor, mixed
Give an example of each of the 4 classifications of cranial nerves:
Sensory: trigeminal (V), mixed sensory and motor
Special sensory: I and II (olfactory and optic)
Motor: Trochlear & abducens (IV and VI) – ee movements
Mixed: Glossopharyngeal (IX) – sensory and motor
Name 3 functions of the medulla oblongata
- Coordinates complex autonomic reflexes
- Allows brain & spinal cord to communicate
- Controls visceral functions
What are the 3 groups of the nuclei in the medulla?
Sensory & motor nuclei of cranial nerves
Relay stations along sensory & motor pathways
Autonomic nuclei
What do autonomic nuclei of the medulla have?
Reflex centers that control peripheral systems like cardiovascular and respiratory rhythm center
Sensory and motor nuclei of the medulla are associated with…
cranial nerves #8 - #12
What are the relay stations of the medulla?
- Nucleus gracilis & cuneatus (pass somatic sensory info to thalamus)
- solitary nucleus: receives visceral sensory info
- olivary (olives): relay info about somatic motor commands
What does the pons link?
The pons links the mesencephalon, diencephalon, cerebrum and spinal cord.
What cranial nerves are associated with the pons?
Cranial nerves #5-8 (sensory & motor nuclei)
What are the 2 functions of the cerebellum?
Adjusts postural muscles
Fine-tunes conscious & subconscious movements
What is a disorder of the cerebellum?
Ataxia (from damage by trauma or stroke or temporary impairment from intoxication). It disturbs muscle coordination
What is the function of grey matter in the cerebellum?
Cerebellar cortex & nuclei: Involuntary coordination and control of ongoing body movements
What is the function of white matter in the cerebellum?
Arbor vitae connects cerebellar cortex with p cerebellar peduncles
Cerebellar peduncles link the cerebellum with the medulla and spinal cord, (and everything else),
What is the main function of the diencephalon?
Integrates sensory info and motor commands
What are the 3 parts of the diencephalon?
Thalamus, epithalamus and hypothalamus
Where is the pineal gland? What is its function?
In the epithalamus. It secretes melatonin (a sleep hormone)
Which ventricle does the thalamus contain? what does it do?
The 3rd ventricle. It separates the left and right thalamus
What re the 5 groups of thalamic nuclei?
Anterior, medial, ventral, posterior and lateral
Which of the thalamic nuclei groups govern emotion?
anterior, medial and lateral
What does the ventral and posterior group of thalamic nuclei govern?
Sensory info
What are the 3 parts of the hypothalamus?
Mamillary bodies, infundibulum and tuberal area
What are the 8 functions of the hypothalamus?
- Controls autonomic function
- Provides subconsciouss control of skeltal muscle
- Coordinate activies of nervous & endocrine systems
- Secretes hormones – ADH (antidiruetic hormone) for kidneys and Oxytocin (hormone secreted during labor). These are produced in the hypothalamus.
- Produces emotional and behavioral drives
- Coordinates voluntary & autonomic functions
- Regulates body temp
- Controls circadian rhythms (day-night cycles)
Name the cranial nerves and their function
I. Olfactory nerve – smell
- Optic nerve – sight
- Oculomotor nerve – eye movement
- Trochlear nerve – eye movement (up/down)
- Trigeminal nerve –Mixed motor & sensory to face– optic, maxillary and mandibular
- Abducens - eye movement side-to-side
- Facial nerves – Mixed – sensory & motor
- Vestibulocochlear – balance, hearing, equilibrium
- Glossopharyngeal – Mixed sensory and motor – poterior 1/3 of tongue, carotid arteries, pharynx
- Vagas – mixed (sensory & motor) – thoracic & diaphragm
- Accessory – motor to muscles of neck and upper back
- Hypoglossal – motor (tongue movements)
