EXAM3 - Neuro Flashcards
What are the structures included in hindbrain?
Medulla, pons, cerebellum
What structures are in the midbrain?
Subsantia nigra
What structures are in the forebrain?
Cerbral cortex, basal ganglia (except SN): striatum (caudate and putamen), globus pallidus, subthalamic nucleus, limbic system: hippocampus and amygdala, and the diencephalon: thalamus, hypothalamus
What is the role of the medulla?
AUTONOMIC functions. centers for controlling respiration, cardiac function, vasomotor responses, reflexes(coughing), part of reticular system (modulates sleep/wake cycles, part of brain stem
What is the role of the pons?
It is a bridge that relays signals from the forebrain to the cerebellum. It is part of the brainstem. (equilibrium, stability, facial and eye movements)
What is the role of the cerebellum?
“little brain” Governs motor coordination for producing smooth movements, undergoes neurodegeneration in spinocerebellar ataxias
What is the role of substantia nigra?
Produces and releases dopamine in the striatum. Two parts: pars compacta, pars reticulata
What is the role of the pars compacta?
Provides INPUT to the basal ganglia, supplies dopamine to the striatum. Involved in voluntary motor control and some cognitive learning (spatial learning). This is impacted in parkinsons Dz.
What is the role in pars reticulata?
OUTPUT function: relays signals from the basal ganglia to the thalamus
What is the role of the cortex?
processing and interpreting information
role of basal ganglia?
voluntary motor control, some cognitive function
role of limbic system?
emotions (amydala)
memory (hippocampus) = alzheimers dz
role of thalamus?
relay station to and from cortex. NO autonomic function
Senses receive information about the environment, passes through the thalamus, to the cortex and back.
Role of hypothalamus?
no voluntary functions. Regulates internal homeostasis, emotions, hormonal control and direct neural regulation
True or False: Damage to the cortex can affect movement, speech and personality
True
What do EFFERENT neuron tracts do?
transmit signals from the cortex to the periphery
What do AFFERENT neuron tracts do?
Transmit signals from the periphery to the cortex
What are the 3 layers of the meninges?
Dura: outer
Arachnoid: middle
Pia: inner
CSF fill spaces between the ___________and __________layers.
arachnoid and pia
What are the 3 types of glial cells?
Astrocytes, oligodendrocytes, and Microglia
What is the role of Astrocytes?
provide neurons with growth factors, antioxidants. Remove excess glutamate, support the blood brain barrier b/c in contact with blood vessels
What do the Oligodendrocytes do?
Produce myelin sheath that insulates axons
What do the microglia do?
Provide growth factors, clear debris by phagocytosis (this can lead to neuroinflammation so need a balance here)
What creates the blood brain barrier?
Tight junctions in the endothelial cell layer of blood vessels in the brain
What 3 characteristics allow a molecule to pass through the blood brain barrier?
Small molecular size
High Log P
the more lipophilic the better
In a resting membrane potential of a neuron, are there more positive charges outside or inside the membrane?
Outside
What triggers neurotransmission in a neuron?
electrical depolarization of the neuron. Influx of Na+ that changes the polarity of the membrane.
True or False
Axon potentials are propagated at a rate independent of the axon diameter.
FALSE
They are propagated proportional to axon diameter. The bigger the diameter the faster the action potential.
What is a nerve fiber?
bundle of axons
Why is the current of a nerve fiber greater than that of a single neuron?
Because the nerve fiber is a summation, more frequent firing.
Excitatory neurotransmitters allow _____ to cross the membrane leading to a increase in the magnitude of the ________. Inhibitory neurotransmitters allow ___to cross the membrane leading to ____________.
Na+ leading to depolarization (easier to fire)
Cl in leading to hyperpolarization (harder to fire)
What type of neurotransmitter is GABA and what is its role in pharmacology?
GABA is an inhibitory neurotransmitter in the brain. Drugs that interact with these receptors are generally CNS depressants such as: Sedatives, Anticonvulsants and Anxiolytics
