Test 2: Anatomy Flashcards
Neuraxis
imaginary line drawn through the spinal cord up to the front of the brain
Anterior (rostral)
Toward the head
Posterior (caudal)
Toward the tail
ventral (inferior)
Toward the “belly”
Dorsal (superior)
Toward the back (top of the head)
Lateral
Toward the side
Medial
Toward the middle
Ipsilateral
Same side of the brain
Contralateral
Opposite side of the brain
Transverse plane
divides front and back of brain
Sagital plane
divides left and right sides of brain
Horizontal plane
divides top and bottom of brain
CT scan
Roentgen-ray computed tomography. Utilizes differential blocking of x-rays as they travel through the skull
MRI
Magnetic resonance imaging. Utilizes the oscillation of protons placed in a magnetic field
PET scan
Position emission computed tomography. Utilizes radiolabeled compounds injected in tracer amounts and reflect activity
Meninges
- Dura mater-thick layer
- Arachnoid- overlies the subarachnoid space filled with CSF. Blood vessels run through the arachnoid layer
- Pia mater-overlies every detail of the outer brain
Brain ventricles
Hold CSF
Access point for drug studies
Can expand when brain cells are lost
Where is cerebrospinal fluid produced and how does it get to other parts of NS?
Choroid plexus. It flows through the lateral venticles to the 3rd ven through the intraventicular foramen.
Then CSF flows into the 4th ven through the cerebral aqueduct.
CSF then flows into the subarachnoid space
Hindbrain consists of
Myelencephalon (medulla oblongata) and metaencephalon (pons and cerebellum)
Medulla oblongata
- Most caudal portion of brain and is rostral to the spinal cord
- contains part of the reticular formation
- nuclei of the medulla control vital functions such as the regulation of the cardiovascular system, breathing, and skeletal muscle tone
Pons
- Contains core of reticular formation
- Pons is involved in the control of sleep and arousal
cerebellum
Involved in motor control
Midbrain
Mesencephalon, tectum, tegmentum, reticular formation
Tectum
Dorsal portion of midbrain. Contains:
- Superior colliculi-involved in visual systems
- Inferior colliculi-involved in auditory systems
Tegmentum
Located under the tectum and consists of smaller parts that relate to pain, motor system, and rostal end of retic form
Reticular fomation
Regulates sleep and wakefulness and modulates muscle reflexes, breathing, and pain perception
Acetylcholine comes from
LDT and PPT.
Sometimes considered dorsolateral pons
Dopamine comes from
Substantia nigra (part of tegmentum) and VTA
Norepinephrine comes from
Locus coeruleus (dorsal wall of the rostal pons in hindbrain)
Serotonin comes from
raphe nuclei located in reticular formation in hindbrain
Forebrain
Diencphalon (thalamus and hypothalamus) and telecephalon (basal ganglia and corpus striatum)
Thamus
Contains nuclei that receive sensory info and transmit it to cortex
Hypothalmus
Contains nuclei involved in integration of species-typical behaviors, control of the autonomic nervous system and pituitary
What does the Basal Ganglia consists of?
- Globus pallidus
- Putamen
- Caudeate nucleus (last two called striatum for short)
Basal Ganglia and cerebellum commonalities
Inception, programming, and termination of
movement
• Equilibrium
• Maintain muscle tone/posture
• Compares intent to actual position of muscles
Proprioception – feedback from muscles, tendons, and
bones
Basal ganglia and cerebellum differences
Basal Ganglia • Slow, smooth movements • Turning of torso, twisting (hips and shoulder) • Posture • Arm swinging Cerebellum • Discrete, fine movements • Equilibrium
Pathway for movement
Know about this
Parkinson’s Disease
Loss of dopaminergic cells of the nigrostriatal dopamine
pathway, which connects the striatum and substantia
nigra
Symptoms of weakness, tremors, rigidity of limbs, poor
balance, difficulty initiating movements
Huntington’s Disease
Chorea is an abnormal voluntary movement disorder, one of a group of neurological disorders called dyskinesias. *Over inhibition of GPi* Fatal inherited disorder Movement disorder Uncontrollable jerking movements, writhing movements, and dementia Atrophy of cerebral cortex and basal ganglia Leads to dementia
Limbic system
In telencesphalon Hippocampus – involved in learning and memory; spatial memory • Amygdala – involved in emotion, fear • Fornix – fiber bundle that interconnects the hippocampus with the mammillary bodies • Mammillary Bodies – memory circuit, connected to hypothalamus
Corpus callosum
Connects areas of neocortex on each side of brain • Largest commissure • Commissure – a fiber bundle that connects each side of the brain In Telencephalon
See Summary of anatomical subdivisions of the brain
See Summary of anatomical subdivisions of the brain
Amygdala
Plays a role in the physiological and bx-al reactions to objects and situations that have bio significance:
• Warnings of pain or other unpleasant consequences
• Presence of food, water, salt
• Presence of potential mates or rivals
• Infants in need of care
Amygdaloid complex
- Lateral nuclei-sensory input and sends it elsewhere
- Central nucleus-sends info to other parts of the brain (think: downstairs brain). Single most important part of the brain for the expression of emotional response provoked by aversive S
- Medial nucleus-relays smells to medial basal forebrain and hypothalamus
Role of 5-HT
Inhibit aggression
Ventral Prefrontal cortex
- Has inhibitory connections with the amygdala. Can suppress conditioned emo responses (facilitates extinction)
- Provides info about ongoing emo states and predicted consequences of actions.
Spinal cord white and grey matter
White matter on outside (myelinated axons), grey matter on inside
Cranial nerves
- Olfactory
- Optic
- Oculomotor
- Trochlear
- Trigeminal
- Abducens
- Facial
- Vestibulocochlear
- Glossopharyngeal
- Vagus
- Spinal Accessory
- Hypoglossal
Sensory neurons
Afferent neurons. Input from dorsal side of spinal cord.
Motor Neurons
Efferent neurons. Output through ventral side of spinal cord
Autonomic nervous system
The ANS is responsible for monitoring conditions
in the internal environment and bringing about
appropriate changes in them.
The contraction of both smooth muscle and
cardiac muscle is controlled by motor neurons of
the autonomic system.
Somatic vs Autonomic
Somatic • Both afferent and efferent neurons • All neuron to neuron synapses within the CNS Organ of intervention: striated muscles. Differentiated. Autonomic • Only efferent neurons • Several synapses in PNS • Organ of intervention Smooth muscles Cardiac muscles Glands • Whole
