Neurotransmitters
What are the amines transmitters?
dopamine, epinephrine, histamine, norepinephrine, serotonin
What is the premotor cortex responsible for?
planning of movements
When does myelination begin and end?
4 mo in utero- 3y/o
When do the cranial and caudal neuropores close?
cranial- by day 27
caudal- by day 30
are ligand-gated ion channels fast or slow?
fast
What are the excitatory amino acids?
glutamate, aspartate
What layers are dominant in the primary somatosensory cortex?
2- granule cells
4-granule/stellate cells
When is the CNS most susceptible to major malformations
day 14-20
What do neuroblasts and glioblasts develop into?
neuroblasts- neurons
glioblasts- glia (macroglia)
What is the most common second messenger in neurons?
cyclic adenosine monophasphate cAMP
What are the agonists and antagonists of opioids?
agonists: morphine, heroin, oxycodone
antagonists: naloxone
What is astereognosis?
lack of object recognition despite intact sensory system
What is growing into deficit?
NS damage occurring early in development is not evident until the damaged system normally becomes functional
dermatome- develops into dermis of skin
sclerotome- develops into axial skeleton
myotome- develops into skeletal muscle
What are the advantages of electrical synapses?
rapid signal transmission, virtually no synaptic delay
What happens with too little dopamine?
parkinson's disease
what happens in a lesion to the lateral prefrontal cortex?
lack of goal-oriented behavior, lack of conscientiousness, inability to generate alternative possibilities
What causes anencephaly?
when the cranial end of the tube remains open and the forebrain doesn't develop, skull doesn't form over incomplete brain, leaving the malformed brainier and meninges exposed
What do the mantle and marginal layers develop into?
mantle- gray matter
Marginal- white matter
What is the second messenger concept?
Neurotransmitter binding to its receptor will active an enzyme (effector enzyme) that results in the formation of another chemical inside the cell (called second messenger)
Responsible for intracellular effect
What is the difference between GABA(A) and GABA(B)?
A- receptors act as Cl- channels that hyper polarize the postsynaptic membrane
B- receptors open ion channels (K+ channels) through G-protein activity- hyper polarizes postsynaptic membrane
What is the difference between Broca's area and wernicke's area
broca- language production
wernicke's- language comprehension
What are the types of arnold-chiari?
Type 1- often asymptomatic
Type 2- causes progressive hydrocephalus, paralysis of the SCM, deafness, bilateral weakness of lateral eye movements and facial weakness
What are the types of spina bifida?
Spina bifida occulta- 1 vertebrae does not fuse and there is no neurological symptoms, it is most common in the lower lumbar region, a tuft of hair is common at the sight of it, people w/ this are usually asymptomatic
Spina bifida menigocele- more than 1 vertebrae does not fuse and there is a fluid filled cyst that extends through that opening, the contents of the cyst determines how severe the case is
Spina bifida meningomyelocele- more than 1 vertebrae does not fuse, spinal cord is displaces in that cyst, neral symptoms are worse
Spina bifida myeloschisis- the lamina and spinous process did not form properly so the spinal cord the open
What are the methods for neurotransmitter inactivation?
enzymatic degradation- neurotransmitter is broken down by enzyme in the synaptic cleft
diffusion- the neurotransmitter just diffuses away from the receptor site
reuptake- neurotransmitter may be reabsorbed into the presynaptic membrane