Basic Neuroanatomy and Circuits Flashcards
What does the brain serve as, mediating interactions between local and global environment and determining appropriate behavior output?
Black box
How do we study the brain?
Genes –> Cells –> Circuits –> Organs –> Gene x Environment –> Behavior
What are behaviors (3 things)?
- Interactions w the environment
- Actions controlling the body (breathing, BP, reflexes)
- Mental activities (learning, writing, etc)
How do we study behaviors? (5 things)
Using the scientific method
- Observation
- Interpretation
- Verification (replication)
- Inductive reasoning (no hyp. to guide, start first w observations)
- Deductive reasoning (global hyp tested)
Galen…
and his humors
Renee Descartes
Mind body dualism
Galvani
electrical impulses
Gall
phrenology
Ramon y Cajal
Individual neurons
Dale and Loewi
chemical transmission from brain to muscle
CNS includes the …
brain and spinal cord
PNS includes the…
somatic and autonomic systems
Rostral
front
caudal
back
anterior
front
posterior
back
dorsal
top
ventral
bottom
Forebrain includes the (brain structures)
Telencephalon
Diencephalon
Midbrain include the (brain structures)
Superior colliculus (visual) Inferior Colliculus (auditory)
Hindbrain includes the (brain structures)
Medulla
Cerebellum
Pons
Parts of the telencephalon
Cerebral hemispheres (4 lobes)
Amygdala
Hippocampus
Basal Ganglia
Parts of the Diencephalon
Thalamus
Hypothalamus
How many lobes in the cerebral hemisphere?
4 lobes
The Amygdala controls the
emotions
The Hippocampus controls the
memory
the Basal Ganglia controls the
involuntary movement
The thalamus is the
gateway to and from the forebrain
the hypothalamus is the
relay station for internal regulatory systems
The superior colliculus controls…
vision
the inferior colliculus controls…
auditory
Medulla does…
autonomic functions
Cerebellum does…
learned motor responses
Pons is the…
relay between cerebellum and cerebrum
Occipital lobe does…
vision
temporal lobe does…
audition, speech and some memory
parietal lobe does…
sensory responses
frontal lobe does
motor control and executive functions
Keep extracellular spaces clean, provide glucose to active neurons, redirect blood flow to needy areas, scavages damaged neurons
Astrocytes
rovide myelin (cellular insulation) for neurons, allowing for fast transmission of action potential
Oligodendrocytes
Astrocytes and Oligodendrocytes are examples of…
Glia
What is vasculature responsible for?
Providing oxygenated blood to neurons
Why is neuronal vasculature not continuous with neurons?
Because of the highly selective blood brain barrier that prevents transmission of large particles from blood to brain
What can pass through the blood brain barrier?
Small lipophilic molecules (hydrophobic)
T or F, Some hydrophilic molecules can pass through the BBB, because membrane transporters exist
True
T or F, Amino Acids can pass through BBB?
True
L-Dopa (Amino Acid) can or cannot pass the BBB?
Can
Dopamine (Amino Acid) can or cannot pass the BBB?
Cannot
What happens due to leaky vasculature, absent normal barrier, permitting relatively rapid nutrient exchange between blood and tumor, facilitating growth of the tumor.
Brain tumors
What happens due to increased water content in brain. Cytotoxic brain edema following cerebral ischemia, causes damage to cells, neurons and glia. Damage causes the membrane pumps to fail, leading to water accumulation inside the cells
Edema
outer membranes between skull and brain, made of connective tissue
Meninges
Between the meninges and brain is
cerebrospinal fluid (CSF)
CSF is made by the…
choroid plexus
CSF also pools in ventricular system which includes
lateral, 3rd, and 4th ventricles which are continuous with each other and space around spinal cord
Neurons communicate w eachother at
synapses
Mitochondria
Energy source
Microtubules-
provide structural support
internal membrane channels that distribute cellular products
Endoplasmic reticulum-
Smooth endoplasmic reticulum-
packages secretory products (synaptic vesicles)
(manufactures secretory products and cells needed products) reside on rough ER or are unattached in the cytoplasm
Ribosomes
found only in cytoplasm of soma and dendrites
rER and ribosomes
found only in axons
synaptic vescicles
Intracellular is positive or negative?
negative
_____, ______ & ______ channels in the plasma membrane allow for ion flow
Potassium, sodium, and chloride
What happens to NTs in synapse? (4 things)
- Bind to post-synaptic receptors
- Bind to pre-synaptic autoreceptors
- Re-uptake by pre-synaptic pumps
- Enzymatic degradation
Below are part of what NT family?
- Glutamate and aspartate
- Glycine and gamma-aminobutyric acid (GABA)
Amino Acid
Monoamines are synthesized from…
Amino Acids
Below are part of what NT family?
Catecholamines:
– Dopamine (DA), norepinephrine (NE), epinephrine,
Monoamines
Below are part of what NT family?
Indolamine:
– serotonin (5-HT)
Monoamines
Below are part of what NT family?
Acetylcholine (ACh)
Monoamines
Below are part of what NT family?
Oxytocin, vasopressin, glucagon related peptide, pancreatic polypeptide related peptides, opioids
Peptides
Product of at least 2 amino acids linked together
Peptides
Acetylcholine is used in PNS to
contract muscles
In the upper midbrain, Acetylcholine targets….
Thalamus, brain stem and some hypothalamus
In the anterior hypothalamus and central septum, Acetylcholine targets…
cortex, hippocampus and olfactory bulbs
implicated in Alzheimers disease
All Catecholamine are synthesized from amino acid…
tyrosine
Found in midbrain (substantia nigra and ventral tegmentum)
Dopamine
Involved in emotion regulation, movement, drug abuse, and reward
Dopamine
Found in locus coeruleus in CNS
Norepinephrine
Found in adrenal gland in PNS
Norepinephrine
Involved in emotional arousal, drug abuse, reward, regulating sleep and mood
Norepinephrine
Found throughout medulla in CNS
Epinephrine
Found in adrenal gland in PNS
Epinephrine
Involved in CNS participation in regulating blood pressure
Epinephrine
Found in raphe nuclei in the pons
Serotonin
Involved in temperature regulation, sensory perception, onset of sleep, and mood
Serotonin
Not exclusive to CNS, also found in pituitary, other endocrine glands, and the immune system
Peptides
Concentration of peptides in CNS much lower than
Amino Acid or monoamine transmitters
Examples of peptides
Vasopressin and Oxytocin
These NT can be released directly into bloodstream
Vasopressin and Oxytocin
facilitates water retention in kidney
Vasopressin
stimulates milk-ejection reflex in moms of newborns
Oxytocin
thought to be involved in maternal-infant attachment and other social behaviors
Vasopressin and Oxytocin
What determine whether a NT is excitatory or inhibitory on each neuron
Receptors
This receptor changes membrane permeability to ions that either excite or inhibit neurons
Ligand gated ion channel receptor
This receptor type is the majority of receptors for the amino acid transmitters, some for acetylcholine, and 1 for 5-HT
Ligand gated ion channel receptor
This receptor works indirectly to change excitability of their neurons by changing intracellular Ca2+, or intracellular 2nd messengers (by binding to G-proteins, ie Gs, Gi)
G-protein coupled receptor